EOVSA Wiki - User contributions [en]

Polarization Mixing Due to Feed Rotation

2025-06-03T19:16:55Z

Dgary: /* Further update */

[[File:parallactic.png|thumb|400px|'''Fig. 1:''' Parallactic angle versus hour angle for sources at different declinations. There is a large deviation for sources whose Dec = latitude (37 degrees), when they pass directly overhead.]]

= Explanation of Polarization Mixing =
The newer 2.1-m antennas [Ants 1-8 and 12] have AzEl (azimuth-elevation) mounts (also referred to as AltAz; the terms Altitude and Elevation are used synonymously), which means that their crossed linear feeds have a constant angle relative to the horizon (the axis of rotation being at the zenith). The older 2.1-m antennas [Ants 9-11 and 13], and the 27-m antenna [Ant 14], have Equatorial mounts, which means that their crossed linear feeds have a constant angle with respect to the celestial equator, the axis of rotation being at the north celestial pole. Thus, the celestial coordinate system is tilted by the local co-latitude (complement of the latitude). This tilt results in a relative feed rotation between the 27-m antenna and the AzEl mounts, but not between the 27-m and the older equatorial mounts. This angle is called the "parallactic angle," and is given by:

<center><math>\chi = \arctan(\cos\lambda \sin A, \sin\lambda \cos E - \cos\lambda \sin E \cos A)</math>,</center>

where <math>\lambda</math> is the site latitude, <math>A</math> is the Azimuth angle [0 north], and <math>E</math> is the Elevation angle [0 on horizon]. This function obviously changes with position on the sky, and as we follow a celestial source (e.g. the Sun) across the sky this rotation angle is continuously changing in a surprisingly complex manner as shown in '''Figure 1'''. Note that <math>\chi=0</math> at zero hour angle for declinations less than the local latitude (37.233 degrees at OVRO), but is <math>\pm \pi</math> at higher declinations.

[[File:Feed_diagram.PNG|thumb|400px|'''Fig. 2:''' Illustration of 27-m feed horns (left), 2.1-m feed package (middle), and rotation of feed orientation by parallactic angle <math>\chi</math> (right). Note that the feeds are all oriented at 45-degrees from the horizontal at 0 hour angle, with X (= H) shown in yellow, and Y (=V) shown in blue.]]

The crossed linear dipole feeds on all antennas are oriented with the X-feed as shown in '''Figure 2''', at 45-degrees from the horizontal, when the antenna is pointed at 0 hour angle. This is the view as seen looking down at the feed from the dish side, although since the feeds are at the prime focus this is the same as the view projected onto the sky. At other positions, the feeds on the AzEl antennas experience a rotation by angle <math>\chi</math> relative to the equatorial antennas.

Because of this rotation, the normal polarization products XX, XY, YX and YY on baselines with dissimilar antennas (one AzEl and the other equatorial) become mixed. The effect of this admixture can be written by the use of Jones matrices (see [[Media:1996A+AS_117_137H.pdf|Hamaker, Bregman & Sault (1996)]] for a complete description). Consider antenna A whose feed orientation is rotated by <math>\chi</math>, cross-correlated with antenna B with unrotated feed. The corresponding Jones matrices, acting on signal vector <math>\boldsymbol{e}_{in} = [X,Y]</math> are:

<center><math>
\boldsymbol{e}_{A,out} = J_A\boldsymbol{e}_{A,in} = \begin{bmatrix}
1 & 0 \\
0 & a_1
\end{bmatrix}\begin{bmatrix}
\cos\chi_1 & \sin\chi_1 \\
-\sin\chi_1 & \cos\chi_1
\end{bmatrix}
\begin{bmatrix}
X_A \\
Y_A
\end{bmatrix}
\qquad\qquad
\boldsymbol{e}_{B,out} = J_B\boldsymbol{e}_{B,in} = \begin{bmatrix}
1 & 0 \\
0 & a_2
\end{bmatrix}
\begin{bmatrix}
X_B \\
Y_B
\end{bmatrix}
</math></center>

and the cross-correlation is found by taking the outer product, i.e.

<center><math>
<\boldsymbol{e}_{A,out}\otimes\boldsymbol{e}^*_{B,out}> = J_A \otimes J^*_B<\boldsymbol{e}_{A,in}\otimes\boldsymbol{e}^*_{B,in}>
</math></center>
which relates the output polarization products to the input as
<center><math>
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{out}
=
\begin{bmatrix}
\cos\chi_1 & 0 & \sin\chi_1 & 0 \\
0 & a_2^*\cos\chi_1 & 0 & a_2^*\sin\chi_1 \\
-a_1\sin\chi_1 & 0 & a_1\cos\chi_1 & 0 \\
0 & -a_1a_2^*\sin\chi_1 & 0 & a_1a_2^*\cos\chi_1
\end{bmatrix}
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{in} \qquad\qquad (1)
</math></center>

where we have dropped the subscripts and complex conjugate notation for brevity. Of course, there are other effects such as unequal gains and cross-talk between feeds that are also at play, but for now we ignore those and focus only on the effect of this polarization mixing due to the parallactic angle.

= Absolute vs. Relative Angle of Rotation =

However, the above description fails when we consider a rotation on both antennas, so that

<center><math>
\boldsymbol{e}_{A,out} = J_A\boldsymbol{e}_{A,in} = \begin{bmatrix}
1 & 0 \\
0 & a_1
\end{bmatrix} \begin{bmatrix}
\cos\chi_1 & \sin\chi_1 \\
-\sin\chi_1 & \cos\chi_1
\end{bmatrix}
\begin{bmatrix}
X_A \\
Y_A
\end{bmatrix}
\qquad\qquad
\boldsymbol{e}_{B,out} = J_B\boldsymbol{e}_{B,in} = \begin{bmatrix}
1 & 0 \\
0 & a_2
\end{bmatrix}\begin{bmatrix}
\cos\chi_2 & \sin\chi_2 \\
-\sin\chi_2 & \cos\chi_2
\end{bmatrix}
\begin{bmatrix}
X_B \\
Y_B
\end{bmatrix}
</math></center>

In this case, performing the outer product gives:

<center><math>
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{out}
=
\begin{bmatrix}
\cos\chi_2\cos\chi_1 & \cos\chi_2\sin\chi_1 & \sin\chi_2\cos\chi_1 & \sin\chi_2\sin\chi_1 \\
-a_1\cos\chi_2\sin\chi_1 & a_1\cos\chi_2\cos\chi_1 & -a_1\sin\chi_2\sin\chi_1 & a_1\sin\chi_2\cos\chi_1 \\
-a_2^*\sin\chi_2\cos\chi_1 & -a_2^*\sin\chi_2\sin\chi_1 & a_2^*\cos\chi_2\cos\chi_1 & a_2^*\cos\chi_2\sin\chi_1 \\
a_1a_2^*\sin\chi_2\sin\chi_1 & -a_1a_2^*\sin\chi_2\cos\chi_1 & -a_1a_2^*\cos\chi_2\sin\chi_1 & a_1a_2^*\cos\chi_2\cos\chi_1
\end{bmatrix}
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{in}
</math></center>

whereas intuitively we want something like:

<center><math>
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{out}
=
\begin{bmatrix}
\cos(\chi_2-\chi_1) & 0 & \sin(\chi_2-\chi_1) & 0 \\
0 & \cos(\chi_2-\chi_1) & 0 & \sin(\chi_2-\chi_1) \\
-\sin(\chi_2-\chi_1) & 0 & \cos(\chi_2-\chi_1) & 0 \\
0 & -\sin(\chi_2-\chi_1) & 0 & \cos(\chi_2-\chi_1)
\end{bmatrix}
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{in}
</math></center>

which becomes the identity matrix when <math>\chi_1 = \chi_2</math>, i.e. when the feeds on two antennas of a baseline are parallel. The difference seems to be that the earlier expression evaluates to components of X and Y in an absolute coordinate frame, whereas we are interested only the difference in angle of the feeds in a relative coordinate frame. This choice no doubt has implications for measuring Stokes Q and U, but for solar data we are not concerned with linear polarization.

One way to achieve this in the framework of Jones matrices is to form Mueller matrices from the outer-product of the rotation times the gain matrix:

<center><math>
M_1 = I \otimes R_1 = \begin{bmatrix}
1 & 0 \\
0 & 1
\end{bmatrix} \otimes \begin{bmatrix}
\cos\chi_1 & \sin\chi_1 \\
-\sin\chi_1 & \cos\chi_1
\end{bmatrix} =
\begin{bmatrix}
\cos\chi_1 & 0 & \sin\chi_1 & 0 \\
0 & \cos\chi_1 & 0 & \sin\chi_1 \\
-\sin\chi_1 & 0 & \cos\chi_1 & 0 \\
0 & -\sin\chi_1 & 0 & \cos\chi_1
\end{bmatrix}
</math></center>

and

<center><math>
M_2 = I \otimes R_2 = \begin{bmatrix}
1 & 0 \\
0 & 1
\end{bmatrix} \otimes \begin{bmatrix}
\cos\chi_2 & \sin\chi_2 \\
-\sin\chi_2 & \cos\chi_2
\end{bmatrix} =
\begin{bmatrix}
\cos\chi_2 & 0 & \sin\chi_2 & 0 \\
0 & \cos\chi_2 & 0 & \sin\chi_2 \\
-\sin\chi_2 & 0 & \cos\chi_2 & 0 \\
0 & -\sin\chi_2 & 0 & \cos\chi_2
\end{bmatrix}
</math></center>

then form an overall matrix
<center><math>M = M_1 M_2^T = \begin{bmatrix}
\cos\Delta\chi & 0 & \sin\Delta\chi & 0 \\
0 & \cos\Delta\chi & 0 & \sin\Delta\chi \\
-\sin\Delta\chi & 0 & \cos\Delta\chi & 0 \\
0 & -\sin\Delta\chi & 0 & \cos\Delta\chi
\end{bmatrix}
</math></center>,
where <math>\Delta\chi = \chi_2 - \chi_1</math>.

= Effect of an X - Y Delay =
Regardless of how the math is done, we expect that the result should be dependent on the difference in angle, <math>\Delta\chi</math>, so as a practical solution let us simply replace <math>\chi_1</math> with <math>\Delta\chi</math> and proceed as in section 1.
<center><math>
\boldsymbol{e}_{A,out} = J_A\boldsymbol{e}_{A,in} = \begin{bmatrix}
1 & 0 \\
0 & a_1
\end{bmatrix}\begin{bmatrix}
\cos\Delta\chi & \sin\Delta\chi \\
-\sin\Delta\chi & \cos\Delta\chi
\end{bmatrix}
\begin{bmatrix}
X_A \\
Y_A
\end{bmatrix}
\qquad\qquad
\boldsymbol{e}_{B,out} = J_B\boldsymbol{e}_{B,in} = \begin{bmatrix}
1 & 0 \\
0 & a_2
\end{bmatrix}
\begin{bmatrix}
X_B \\
Y_B
\end{bmatrix}
</math></center>

and the cross-correlation is found by taking the outer product, i.e.

<center><math>
<\boldsymbol{e}_{A,out}\otimes\boldsymbol{e}^*_{B,out}> = J_A \otimes J^*_B<\boldsymbol{e}_{A,in}\otimes\boldsymbol{e}^*_{B,in}>
</math></center>
which relates the output polarization products to the input as
<center><math>
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{out}
=
\begin{bmatrix}
\cos\Delta\chi & 0 & \sin\Delta\chi & 0 \\
0 & a_2^*\cos\Delta\chi & 0 & a_2^*\sin\Delta\chi \\
-a_1\sin\Delta\chi & 0 & a_1\cos\Delta\chi & 0 \\
0 & -a_1a_2^*\sin\Delta\chi & 0 & a_1a_2^*\cos\Delta\chi
\end{bmatrix}
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{in} \qquad\qquad (2)
</math></center>

Now consider that there is a "multi-band" delay on both antennas, <math>\tau_1</math> and <math>\tau_2</math>. Then (2) becomes:
<center><math>
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{out}
=
\begin{bmatrix}
\cos\Delta\chi & 0 & \sin\Delta\chi & 0 \\
0 & e^{-2\pi if\tau_2}\cos\Delta\chi & 0 & e^{-2\pi if\tau_2}\sin\Delta\chi \\
-e^{2\pi if\tau_1}\sin\Delta\chi & 0 & e^{2\pi if\tau_1}\cos\Delta\chi & 0 \\
0 & -e^{2\pi if(\tau_1 - \tau_2)}\sin\Delta\chi & 0 & e^{2\pi if(\tau_1 - \tau_2)}\cos\Delta\chi
\end{bmatrix}
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{in}. \qquad\qquad (3)
</math></center>

The result agrees with our intuition:
<center><math>
\begin{align}
XX_{out} &= \cos\Delta\chi XX_{in} + \sin\Delta\chi YX_{in} \qquad \qquad \qquad \text{(has no phase shift)}\\
XY_{out} &= (\cos\Delta\chi XY_{in} + \sin\Delta\chi YY_{in})e^{-2\pi if\tau_2} \qquad \text{(phase shift depends on} \;\tau_2 \text{)} \\
YX_{out} &= (\cos\Delta\chi YX_{in} - \sin\Delta\chi XX_{in})e^{2\pi if\tau_1} \qquad \text{(phase shift depends on} \;\tau_1 \text{)} \\
YY_{out} &= (\cos\Delta\chi YY_{in} - \sin\Delta\chi XY_{in})e^{2\pi if(\tau_1 - \tau_2)} \qquad \text{(phase shift depends on delay difference)}
\end{align} \qquad\qquad (4)
</math></center>

This approach was implemented, to see how well it does in correcting for the effects of differential feed rotation, but the results were not good. The problem turns out not to be the approach, but the assumption that the X-Y delay is a constant with frequency. The next section describes the actual case, where the X-Y delay is considered in terms of a measured "delay phase."

= Another Look at X-Y Delays =
Prior to doing the feed rotation correction, it is essential that any X-Y delays be measured and corrected. We have devised a calibration procedure in which we take data on a strong calibrator with the feeds parallel, then rotate the 27-m (antenna 14) feed so that they are perpendicular. For an unpolarized source, this results in signal on the XX and YY polarization channels in the first case, and on the XY and YX polarization channels in the second case. As a practical matter, this can be done on all antennas at once if a strong source is observed near 0 HA, ideally timed to start 20 min before 0 HA and completing 20 min after 0 HA. The source 2253+161 works well, as does 1229+006 (3C273). Two observations are needed
:* one with the 27-m feed unrotated (gives parallel-feed data for all dishes, if done near 0 HA). Gives strong signal in XX and YY channels. [http://ovsa.njit.edu/phasecal/20170702/pcF20170702121949_2253+161.png Example]
:* one with the 27-m feed rotated to -90 degrees (gives crossed-feed data for all dishes, if done near 0 HA). Gives strong signal in XY and YX channels. [http://ovsa.njit.edu/phasecal/20170702/pcF20170702115948_2253+161.png Example]

Note that the feed should be rotated by -90, not 90, in order for the signs in the expressions below to be correct.

== Background ==
[[File: 20170702_delay-phase.png | thumb | 300px | '''Figure 1x:''' Example of delay phase measurement for 2017-07-02. Multiple measurements of the delay phase are possible, two for each of the small antennas and 26 for antenna 14. These are shown by the multicolor points. The average of the measurements are shown with black points.]]
In order to correct for feed rotation, it is necessary to measure and correct for any differences in X vs. Y delay. We have devised a way of making this measurement by holding the small antenna feeds fixed and rotating the antenna 14 feed from 0-degree position angle (parallel to the small dish feeds) to -90 degrees position angle (perpendicular to the small dish feeds). In the 0-degree case, the X feeds are all parallel to each other, and the Y feeds are all parallel to each other. In the -90-degree case, the small-dish X feeds are parallel to the antenna 14 Y feed, and the small-dish Y feeds are parallel to the antenna 14 X feed. Comparing the parallel XX vs. crossed XY, the phases should be the same except for any non-zero X vs. Y delay on antenna 14, and a possible secular change in phase due to rotating the feed (<math>\xi_{rot}</math>). Comparing the parallel YY vs. crossed XY, on the other hand, the phases should be the same except for any non-zero X vs. Y delays on the small antennas, plus the effect of <math>\xi_{rot}</math>. Thus, <math>\xi_{rot}</math> = 0 on XX and YY measurements, and non-zero for XY and YX measurements.

We can derive expressions by considering antenna-based phases on X polarization as <math>\phi(X_i) = \phi_i + \delta_{i14}\xi_{rot}</math> and on Y polarization as <math>\phi(Y_i) = \phi_i + d\phi_i + \delta_{i14}\xi_{rot}</math>, i.e. the Y phases are nominally the same as for X, except for a possible X-Y delay difference <math>\tau_i</math>, here written as delay phase <math>d\phi_i = 2\pi\tau_i f</math>. We are finding that this delay is a complicated function of frequency, so it is just as well to keep it in terms of phase. The <math>\xi_{rot}</math> term is only present on antenna 14, hence the use of the Kronecker <math>\delta</math>. As noted above, the term <math>\xi_{rot}</math> is zero if the antenna 14 feed is not rotated (i.e. for XX and YY measurements) and non-zero if it is (for XY and YX measurements). On a baseline <math>(i,j)</math>, then, the four polarization terms become:
<center><math>
\begin{align}
\phi_{ij}(XX) &= \phi(X_j) - \phi(X_i) = \phi_j - \phi_i\\
\phi_{ij}(XY) &= \phi(Y_j) - \phi(X_i) = \phi_j + d\phi_j + \delta_{j14}\xi_{rot} - \phi_i\\
\phi_{ij}(YX) &= \phi(X_j) - \phi(Y_i) = \phi_j + \delta_{j14}\xi_{rot} - \phi_i - d\phi_i\\
\phi_{ij}(YY) &= \phi(Y_j) - \phi(Y_i) = \phi_j + d\phi_j - \phi_i - d\phi_i
\end{align}\qquad\qquad (5)
</math></center>

We then examine the channel differences on baselines with antenna 14 (<math>j=14</math>), i.e.
<center><math>
\begin{align}
\phi_{i14}(XY) - \phi_{i14}(XX) &= \phi_{14} + d\phi_{14} + \xi_{rot} - \phi_i - \phi_{14} + \phi_i &= d\phi_{14} + \xi_{rot}, \\
\phi_{i14}(YY) - \phi_{i14}(YX) &= \phi_{14} + d\phi_{14} - \phi_i - d\phi_i - \phi_{14} - \xi_{rot} + \phi_i + d\phi_i &= d\phi_{14} - \xi_{rot}, \\
\phi_{i14}(XX) - \phi_{i14}(YX) &= \phi_{14} - \phi_i - \phi_{14} - \xi_{rot} + \phi_i + d\phi_i &= d\phi_i - \xi_{rot}, \\
\phi_{i14}(XY) - \phi_{i14}(YY) &= \phi_{14} + d\phi_{14} + \xi_{rot} - \phi_i - \phi_{14} - d\phi_{14} + \phi_i + d\phi_i &= d\phi_i + \xi_{rot}.
\end{align}
</math></center>
Consequently, we can solve redundantly in two ways for the antenna-based delay phases:
<center><math>
\begin{align}
d\phi_i &= \phi_{i14}(XX) - \phi_{i14}(YX) + \xi_{rot} = \phi_{i14}(XY) - \phi_{i14}(YY) - \xi_{rot}, \\
d\phi_{14} &= \phi_{i14}(XY) - \phi_{i14}(XX) - \xi_{rot} = \phi_{i14}(YY) - \phi_{i14}(YX) + \xi_{rot},
\end{align}\qquad\qquad (6)
</math></center>
where we specifically use <math>j=14</math> to emphasize that this quantity for all antennas should be the same value, because the measurements are all baselines with antenna 14. Both of these give the same expression:
<center><math>
2\xi_{rot} = \phi_{i14}(XY) - \phi_{i14}(YY) - \phi_{i14}(XX) + \phi_{i14}(YX),
</math></center>
which, when evaluated for the thirteen different measurements do indeed give the same result within statistical variations. Care must be taken to do an appropriate average to take care of the <math>2\pi</math> phase ambiguity. One way to do this is form unit vectors and sum them, then find the phase of the summed vector. In Python, the following expression calculates an average phase phi_avg from the 13 individual measurements phi, where the sum over index 0 is over antennas:
phi_avg = np.angle(np.sum(np.exp(1j*phi),0))

Once we have this average value of <math>\xi_{rot}</math>, the equations (6) give two measurements for each antenna for <math>d\phi_i</math>, and the 26 measurements for antenna 14 for <math>d\phi_{14}</math>, which can be averaged in the same manner.

'''Figure 1x''' shows the results for a measurement on 2017-07-02.

== Applying the Measurements ==
[[File: 20170702-amp-correction.png | thumb | 600px | '''Figure 2x:''' Amplitude vs frequency for channels XX, YY, XY and YX, on ants 1-13, before (green) and after (black) correction for feed rotation.]]
[[File: 20170702-phase-correction.png | thumb | 600px | '''Figure 3x:''' Phase vs frequency for channels XX, YY, XY and YX, on ants 1-13, before (green) and after (black) correction for feed rotation.]]

Once we have these, we can apply corrections to each of the polarization channels, and then do the feed rotation correction. The corrections are done to data taken in a normal way, without rotating the 27-m feed. The application of the correction is found by removing the effects of the delays and rotations in equation (5):
<center><math>
\begin{align}
\phi_{ij}(XX)' &= \phi_{ij}(XX),\quad\text{no correction} \\
\phi_{ij}(XY)' &= \phi_{ij}(XY) - d\phi_j - \delta_{j14}\xi_{rot}, \\
\phi_{ij}(YX)' &= \phi_{ij}(YX) + d\phi_i - \delta_{j14}\xi_{rot} + \pi, \\
\phi_{ij}(YY)' &= \phi_{ij}(YY) + d\phi_i - d\phi_j,
\end{align}\qquad (6)
</math></center>
where the third term has an offset of <math>\pi</math> because this term should be flipped for negative parallactic angle, i.e. should be <math>\phi_{ij}(YX) = \phi_j - \phi_i + \pi</math>. Again, the Kronecker <math>\delta</math> indicates the fact that this term is applied only for baselines involving antenna 14. After the corrections are applied, we have
<center><math>
\begin{align}
\phi_{ij}(XX)' &= \phi_j - \phi_i \\
\phi_{ij}(XY)' &= \phi_j - \phi_i, \\
\phi_{ij}(YX)' &= \phi_j - \phi_i + \pi, \\
\phi_{ij}(YY)' &= \phi_j - \phi_i.
\end{align}
</math></center>

I tried applying the feed rotation correction for data taken on 2017-07-02, and it does seem to work. '''Figures 2x''' and '''3x''' show the amplitude and phase on all baselines with Ant 14, with light green for data before correction and black for after correction. For ants 1-8 and 12, the XX and YY amplitudes have increased a bit, while the XY and YX amplitudes are much reduced. The corresponding phases are slightly improved in XX and YY, and noise-like for XY and YX (less so on YX for some antennas). For the other antennas, no correction was made since those feeds are already parallel to Ant 14.

The proof of this scheme will be seen when we observe a calibrator for many hours while the parallactic angle changes over HA, and then see that the amplitude time profiles become steady and well behaved.

Ultimately, the X-Y delays will need to be measured periodically (especially if the correlator is rebooted or X and Y delays are changed for other reasons), and then stored as a new calibration type in the SQL database.

== Comparison with the Mathematical Description in the Earlier Section ==
We now want to see how this compares with the mathematical development in the previous section. It turns out that they are the same, as long as we rewrite the expression <math>2\pi f\tau_i = \phi_i - \pi/2</math>. To see this, first write the corrections in equation (6) in matrix form:
<center><math>
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{in}
=
\begin{bmatrix}
\cos\Delta\chi & 0 & -\sin\Delta\chi & 0 \\
0 & \cos\Delta\chi & 0 & -\sin\Delta\chi \\
\sin\Delta\chi & 0 & \cos\Delta\chi & 0 \\
0 & \sin\Delta\chi & 0 & \cos\Delta\chi
\end{bmatrix}
\begin{bmatrix}
1 & 0 & 0 & 0 \\
0 & e^{-i(d\phi_j - \pi/2)} & 0 & 0 \\
0 & 0 & e^{i(d\phi_i - \pi/2)} & 0 \\
0 & 0 & 0 & e^{i(d\phi_i - d\phi_j)}
\end{bmatrix}
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{out}
</math></center>
where now this is the correction applied to the measured (<math>out</math>) data to covert it to the expected (<math>in</math>) data, and hence is the inverse of the matrix (2) in the previous section. Expanding the matrix product, this is
<center><math>
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{in}
=
\begin{bmatrix}
\cos\Delta\chi & 0 & -e^{i(d\phi_i - \pi/2)}\sin\Delta\chi & 0 \\
0 & e^{-i(d\phi_j - \pi/2)}\cos\Delta\chi & 0 & -e^{i(d\phi_i - d\phi_j)}\sin\Delta\chi \\
\sin\Delta\chi & 0 & e^{i(d\phi_i - \pi/2)}\cos\Delta\chi & 0 \\
0 & e^{-i(d\phi_j - \pi/2)}\sin\Delta\chi & 0 & e^{i(d\phi_i - d\phi_j)}\cos\Delta\chi
\end{bmatrix}
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{out}
</math></center>
and converting back to <math>\tau_i</math>, it becomes:
<center><math>
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{in}
=
\begin{bmatrix}
\cos\Delta\chi & 0 & -e^{2\pi if\tau_i}\sin\Delta\chi & 0 \\
0 & e^{-2\pi if\tau_j}\cos\Delta\chi & 0 & -e^{2\pi if(\tau_i-\tau_j)}\sin\Delta\chi \\
\sin\Delta\chi & 0 & e^{i2\pi f\tau_i}\cos\Delta\chi & 0 \\
0 & e^{-2\pi if\tau_j}\sin\Delta\chi & 0 & e^{2\pi if(\tau_i-\tau_j)}\cos\Delta\chi
\end{bmatrix}
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{out}\qquad\qquad (7)
</math></center>
which is precisely the inverse of (3).

= AzEl Antenna Axis Offset =

[[File:3C84_cos-el-rotation.png|right|thumb|300px|'''Fig. 9:''' Observations and simulation of amplitude and phase on 3C84 for baseline Ant 1-14, where a phase shift proportional to <math>{2\pi\over\lambda} \cos E</math> is applied. The agreement is reasonably good except for some curvature, which could be residual baseline error.]]

[[File:3C273_cos-el-rotation.png|right|thumb|300px|'''Fig. 10:''' Observations and simulation of amplitude and phase on 3C273 for baseline Ant 1-14, where a phase shift proportional to <math>{2\pi\over\lambda} \cos E</math> is applied. The agreement is reasonably good, except for some curvature at negative hour angle, which could be residual baseline error.]]

During our investigation of the parallactic angle correction, we noted a "V"-shaped dependence of phase on HA, for the AzEl baselines with Ant 14, that cannot be due to parallactic angle. Dr. Avinash Deshpande (Raman Research Institute, Bangalore -- ''Thanks to Dr. Ananthakrishnan for contacting him'') confirms that no phase rotation is expected for the parallactic correction, aside from the 180-degree phase jump at the meridian crossing. He suggests that a non-intersecting axis is the cause, and this was confirmed. He notes that the effect of non-intersecting axes is a phase rotation of

<center><math>{2\pi\over\lambda} d\cos E</math></center>

where <math>E</math> is the elevation angle, and <math>d</math> is the offset distance. As a test, I applied this function, using d = 11.5 cm (based on the apparent phase variation in the observed phases), and obtained the results in '''Figures 9 and 10'''. Although the observed phases show a bit more curvature than the simulation, this was found to be due to residual baseline errors.

=== Further update ===
[[File:3C84_cos-el-correction.png|left|thumb|300px|'''Fig. 11:''' Observations and phase-corrected observations for 3C84 taken on 2016-11-13, where d = 15.2 cm was applied. Shown are Ant 1-5 baselines with Ant 14. The remaining phase variations are consistent with a residual Bx baseline error.]]

On 2016 Nov 13, new observations of 3C84 were taken, and the correction for the axis offset (d = 15.2 cm) was applied, as shown in '''Figure 11''' (at left). It appears that this correction works well, and that there is a residual baseline error on each of the antennas due to the fact that they were originally determined without the axis-offset correction. --[[User:Dgary|Dgary]] ([[User talk:Dgary|talk]]) 14:20, 15 November 2016 (UTC)

This change was permanently instituted in DPP_PROCESS_STATEFRAME.f90 on 2016-11-16.

'''2025-06-03 NB:''' We have replaced the old antennas (9, 10, 11, and 13) with new antennas and added two more (14 and 15). Caius reports that the new antennas may have a shorter distance d ~ 14 cm. We'll have to measure the phase variation on calibrators and determine if those antennas need a different value of d.

Polarization Mixing Due to Feed Rotation

2025-06-03T19:14:42Z

Dgary: /* Further update */

[[File:parallactic.png|thumb|400px|'''Fig. 1:''' Parallactic angle versus hour angle for sources at different declinations. There is a large deviation for sources whose Dec = latitude (37 degrees), when they pass directly overhead.]]

= Explanation of Polarization Mixing =
The newer 2.1-m antennas [Ants 1-8 and 12] have AzEl (azimuth-elevation) mounts (also referred to as AltAz; the terms Altitude and Elevation are used synonymously), which means that their crossed linear feeds have a constant angle relative to the horizon (the axis of rotation being at the zenith). The older 2.1-m antennas [Ants 9-11 and 13], and the 27-m antenna [Ant 14], have Equatorial mounts, which means that their crossed linear feeds have a constant angle with respect to the celestial equator, the axis of rotation being at the north celestial pole. Thus, the celestial coordinate system is tilted by the local co-latitude (complement of the latitude). This tilt results in a relative feed rotation between the 27-m antenna and the AzEl mounts, but not between the 27-m and the older equatorial mounts. This angle is called the "parallactic angle," and is given by:

<center><math>\chi = \arctan(\cos\lambda \sin A, \sin\lambda \cos E - \cos\lambda \sin E \cos A)</math>,</center>

where <math>\lambda</math> is the site latitude, <math>A</math> is the Azimuth angle [0 north], and <math>E</math> is the Elevation angle [0 on horizon]. This function obviously changes with position on the sky, and as we follow a celestial source (e.g. the Sun) across the sky this rotation angle is continuously changing in a surprisingly complex manner as shown in '''Figure 1'''. Note that <math>\chi=0</math> at zero hour angle for declinations less than the local latitude (37.233 degrees at OVRO), but is <math>\pm \pi</math> at higher declinations.

[[File:Feed_diagram.PNG|thumb|400px|'''Fig. 2:''' Illustration of 27-m feed horns (left), 2.1-m feed package (middle), and rotation of feed orientation by parallactic angle <math>\chi</math> (right). Note that the feeds are all oriented at 45-degrees from the horizontal at 0 hour angle, with X (= H) shown in yellow, and Y (=V) shown in blue.]]

The crossed linear dipole feeds on all antennas are oriented with the X-feed as shown in '''Figure 2''', at 45-degrees from the horizontal, when the antenna is pointed at 0 hour angle. This is the view as seen looking down at the feed from the dish side, although since the feeds are at the prime focus this is the same as the view projected onto the sky. At other positions, the feeds on the AzEl antennas experience a rotation by angle <math>\chi</math> relative to the equatorial antennas.

Because of this rotation, the normal polarization products XX, XY, YX and YY on baselines with dissimilar antennas (one AzEl and the other equatorial) become mixed. The effect of this admixture can be written by the use of Jones matrices (see [[Media:1996A+AS_117_137H.pdf|Hamaker, Bregman & Sault (1996)]] for a complete description). Consider antenna A whose feed orientation is rotated by <math>\chi</math>, cross-correlated with antenna B with unrotated feed. The corresponding Jones matrices, acting on signal vector <math>\boldsymbol{e}_{in} = [X,Y]</math> are:

<center><math>
\boldsymbol{e}_{A,out} = J_A\boldsymbol{e}_{A,in} = \begin{bmatrix}
1 & 0 \\
0 & a_1
\end{bmatrix}\begin{bmatrix}
\cos\chi_1 & \sin\chi_1 \\
-\sin\chi_1 & \cos\chi_1
\end{bmatrix}
\begin{bmatrix}
X_A \\
Y_A
\end{bmatrix}
\qquad\qquad
\boldsymbol{e}_{B,out} = J_B\boldsymbol{e}_{B,in} = \begin{bmatrix}
1 & 0 \\
0 & a_2
\end{bmatrix}
\begin{bmatrix}
X_B \\
Y_B
\end{bmatrix}
</math></center>

and the cross-correlation is found by taking the outer product, i.e.

<center><math>
<\boldsymbol{e}_{A,out}\otimes\boldsymbol{e}^*_{B,out}> = J_A \otimes J^*_B<\boldsymbol{e}_{A,in}\otimes\boldsymbol{e}^*_{B,in}>
</math></center>
which relates the output polarization products to the input as
<center><math>
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{out}
=
\begin{bmatrix}
\cos\chi_1 & 0 & \sin\chi_1 & 0 \\
0 & a_2^*\cos\chi_1 & 0 & a_2^*\sin\chi_1 \\
-a_1\sin\chi_1 & 0 & a_1\cos\chi_1 & 0 \\
0 & -a_1a_2^*\sin\chi_1 & 0 & a_1a_2^*\cos\chi_1
\end{bmatrix}
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{in} \qquad\qquad (1)
</math></center>

where we have dropped the subscripts and complex conjugate notation for brevity. Of course, there are other effects such as unequal gains and cross-talk between feeds that are also at play, but for now we ignore those and focus only on the effect of this polarization mixing due to the parallactic angle.

= Absolute vs. Relative Angle of Rotation =

However, the above description fails when we consider a rotation on both antennas, so that

<center><math>
\boldsymbol{e}_{A,out} = J_A\boldsymbol{e}_{A,in} = \begin{bmatrix}
1 & 0 \\
0 & a_1
\end{bmatrix} \begin{bmatrix}
\cos\chi_1 & \sin\chi_1 \\
-\sin\chi_1 & \cos\chi_1
\end{bmatrix}
\begin{bmatrix}
X_A \\
Y_A
\end{bmatrix}
\qquad\qquad
\boldsymbol{e}_{B,out} = J_B\boldsymbol{e}_{B,in} = \begin{bmatrix}
1 & 0 \\
0 & a_2
\end{bmatrix}\begin{bmatrix}
\cos\chi_2 & \sin\chi_2 \\
-\sin\chi_2 & \cos\chi_2
\end{bmatrix}
\begin{bmatrix}
X_B \\
Y_B
\end{bmatrix}
</math></center>

In this case, performing the outer product gives:

<center><math>
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{out}
=
\begin{bmatrix}
\cos\chi_2\cos\chi_1 & \cos\chi_2\sin\chi_1 & \sin\chi_2\cos\chi_1 & \sin\chi_2\sin\chi_1 \\
-a_1\cos\chi_2\sin\chi_1 & a_1\cos\chi_2\cos\chi_1 & -a_1\sin\chi_2\sin\chi_1 & a_1\sin\chi_2\cos\chi_1 \\
-a_2^*\sin\chi_2\cos\chi_1 & -a_2^*\sin\chi_2\sin\chi_1 & a_2^*\cos\chi_2\cos\chi_1 & a_2^*\cos\chi_2\sin\chi_1 \\
a_1a_2^*\sin\chi_2\sin\chi_1 & -a_1a_2^*\sin\chi_2\cos\chi_1 & -a_1a_2^*\cos\chi_2\sin\chi_1 & a_1a_2^*\cos\chi_2\cos\chi_1
\end{bmatrix}
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{in}
</math></center>

whereas intuitively we want something like:

<center><math>
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{out}
=
\begin{bmatrix}
\cos(\chi_2-\chi_1) & 0 & \sin(\chi_2-\chi_1) & 0 \\
0 & \cos(\chi_2-\chi_1) & 0 & \sin(\chi_2-\chi_1) \\
-\sin(\chi_2-\chi_1) & 0 & \cos(\chi_2-\chi_1) & 0 \\
0 & -\sin(\chi_2-\chi_1) & 0 & \cos(\chi_2-\chi_1)
\end{bmatrix}
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{in}
</math></center>

which becomes the identity matrix when <math>\chi_1 = \chi_2</math>, i.e. when the feeds on two antennas of a baseline are parallel. The difference seems to be that the earlier expression evaluates to components of X and Y in an absolute coordinate frame, whereas we are interested only the difference in angle of the feeds in a relative coordinate frame. This choice no doubt has implications for measuring Stokes Q and U, but for solar data we are not concerned with linear polarization.

One way to achieve this in the framework of Jones matrices is to form Mueller matrices from the outer-product of the rotation times the gain matrix:

<center><math>
M_1 = I \otimes R_1 = \begin{bmatrix}
1 & 0 \\
0 & 1
\end{bmatrix} \otimes \begin{bmatrix}
\cos\chi_1 & \sin\chi_1 \\
-\sin\chi_1 & \cos\chi_1
\end{bmatrix} =
\begin{bmatrix}
\cos\chi_1 & 0 & \sin\chi_1 & 0 \\
0 & \cos\chi_1 & 0 & \sin\chi_1 \\
-\sin\chi_1 & 0 & \cos\chi_1 & 0 \\
0 & -\sin\chi_1 & 0 & \cos\chi_1
\end{bmatrix}
</math></center>

and

<center><math>
M_2 = I \otimes R_2 = \begin{bmatrix}
1 & 0 \\
0 & 1
\end{bmatrix} \otimes \begin{bmatrix}
\cos\chi_2 & \sin\chi_2 \\
-\sin\chi_2 & \cos\chi_2
\end{bmatrix} =
\begin{bmatrix}
\cos\chi_2 & 0 & \sin\chi_2 & 0 \\
0 & \cos\chi_2 & 0 & \sin\chi_2 \\
-\sin\chi_2 & 0 & \cos\chi_2 & 0 \\
0 & -\sin\chi_2 & 0 & \cos\chi_2
\end{bmatrix}
</math></center>

then form an overall matrix
<center><math>M = M_1 M_2^T = \begin{bmatrix}
\cos\Delta\chi & 0 & \sin\Delta\chi & 0 \\
0 & \cos\Delta\chi & 0 & \sin\Delta\chi \\
-\sin\Delta\chi & 0 & \cos\Delta\chi & 0 \\
0 & -\sin\Delta\chi & 0 & \cos\Delta\chi
\end{bmatrix}
</math></center>,
where <math>\Delta\chi = \chi_2 - \chi_1</math>.

= Effect of an X - Y Delay =
Regardless of how the math is done, we expect that the result should be dependent on the difference in angle, <math>\Delta\chi</math>, so as a practical solution let us simply replace <math>\chi_1</math> with <math>\Delta\chi</math> and proceed as in section 1.
<center><math>
\boldsymbol{e}_{A,out} = J_A\boldsymbol{e}_{A,in} = \begin{bmatrix}
1 & 0 \\
0 & a_1
\end{bmatrix}\begin{bmatrix}
\cos\Delta\chi & \sin\Delta\chi \\
-\sin\Delta\chi & \cos\Delta\chi
\end{bmatrix}
\begin{bmatrix}
X_A \\
Y_A
\end{bmatrix}
\qquad\qquad
\boldsymbol{e}_{B,out} = J_B\boldsymbol{e}_{B,in} = \begin{bmatrix}
1 & 0 \\
0 & a_2
\end{bmatrix}
\begin{bmatrix}
X_B \\
Y_B
\end{bmatrix}
</math></center>

and the cross-correlation is found by taking the outer product, i.e.

<center><math>
<\boldsymbol{e}_{A,out}\otimes\boldsymbol{e}^*_{B,out}> = J_A \otimes J^*_B<\boldsymbol{e}_{A,in}\otimes\boldsymbol{e}^*_{B,in}>
</math></center>
which relates the output polarization products to the input as
<center><math>
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{out}
=
\begin{bmatrix}
\cos\Delta\chi & 0 & \sin\Delta\chi & 0 \\
0 & a_2^*\cos\Delta\chi & 0 & a_2^*\sin\Delta\chi \\
-a_1\sin\Delta\chi & 0 & a_1\cos\Delta\chi & 0 \\
0 & -a_1a_2^*\sin\Delta\chi & 0 & a_1a_2^*\cos\Delta\chi
\end{bmatrix}
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{in} \qquad\qquad (2)
</math></center>

Now consider that there is a "multi-band" delay on both antennas, <math>\tau_1</math> and <math>\tau_2</math>. Then (2) becomes:
<center><math>
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{out}
=
\begin{bmatrix}
\cos\Delta\chi & 0 & \sin\Delta\chi & 0 \\
0 & e^{-2\pi if\tau_2}\cos\Delta\chi & 0 & e^{-2\pi if\tau_2}\sin\Delta\chi \\
-e^{2\pi if\tau_1}\sin\Delta\chi & 0 & e^{2\pi if\tau_1}\cos\Delta\chi & 0 \\
0 & -e^{2\pi if(\tau_1 - \tau_2)}\sin\Delta\chi & 0 & e^{2\pi if(\tau_1 - \tau_2)}\cos\Delta\chi
\end{bmatrix}
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{in}. \qquad\qquad (3)
</math></center>

The result agrees with our intuition:
<center><math>
\begin{align}
XX_{out} &= \cos\Delta\chi XX_{in} + \sin\Delta\chi YX_{in} \qquad \qquad \qquad \text{(has no phase shift)}\\
XY_{out} &= (\cos\Delta\chi XY_{in} + \sin\Delta\chi YY_{in})e^{-2\pi if\tau_2} \qquad \text{(phase shift depends on} \;\tau_2 \text{)} \\
YX_{out} &= (\cos\Delta\chi YX_{in} - \sin\Delta\chi XX_{in})e^{2\pi if\tau_1} \qquad \text{(phase shift depends on} \;\tau_1 \text{)} \\
YY_{out} &= (\cos\Delta\chi YY_{in} - \sin\Delta\chi XY_{in})e^{2\pi if(\tau_1 - \tau_2)} \qquad \text{(phase shift depends on delay difference)}
\end{align} \qquad\qquad (4)
</math></center>

This approach was implemented, to see how well it does in correcting for the effects of differential feed rotation, but the results were not good. The problem turns out not to be the approach, but the assumption that the X-Y delay is a constant with frequency. The next section describes the actual case, where the X-Y delay is considered in terms of a measured "delay phase."

= Another Look at X-Y Delays =
Prior to doing the feed rotation correction, it is essential that any X-Y delays be measured and corrected. We have devised a calibration procedure in which we take data on a strong calibrator with the feeds parallel, then rotate the 27-m (antenna 14) feed so that they are perpendicular. For an unpolarized source, this results in signal on the XX and YY polarization channels in the first case, and on the XY and YX polarization channels in the second case. As a practical matter, this can be done on all antennas at once if a strong source is observed near 0 HA, ideally timed to start 20 min before 0 HA and completing 20 min after 0 HA. The source 2253+161 works well, as does 1229+006 (3C273). Two observations are needed
:* one with the 27-m feed unrotated (gives parallel-feed data for all dishes, if done near 0 HA). Gives strong signal in XX and YY channels. [http://ovsa.njit.edu/phasecal/20170702/pcF20170702121949_2253+161.png Example]
:* one with the 27-m feed rotated to -90 degrees (gives crossed-feed data for all dishes, if done near 0 HA). Gives strong signal in XY and YX channels. [http://ovsa.njit.edu/phasecal/20170702/pcF20170702115948_2253+161.png Example]

Note that the feed should be rotated by -90, not 90, in order for the signs in the expressions below to be correct.

== Background ==
[[File: 20170702_delay-phase.png | thumb | 300px | '''Figure 1x:''' Example of delay phase measurement for 2017-07-02. Multiple measurements of the delay phase are possible, two for each of the small antennas and 26 for antenna 14. These are shown by the multicolor points. The average of the measurements are shown with black points.]]
In order to correct for feed rotation, it is necessary to measure and correct for any differences in X vs. Y delay. We have devised a way of making this measurement by holding the small antenna feeds fixed and rotating the antenna 14 feed from 0-degree position angle (parallel to the small dish feeds) to -90 degrees position angle (perpendicular to the small dish feeds). In the 0-degree case, the X feeds are all parallel to each other, and the Y feeds are all parallel to each other. In the -90-degree case, the small-dish X feeds are parallel to the antenna 14 Y feed, and the small-dish Y feeds are parallel to the antenna 14 X feed. Comparing the parallel XX vs. crossed XY, the phases should be the same except for any non-zero X vs. Y delay on antenna 14, and a possible secular change in phase due to rotating the feed (<math>\xi_{rot}</math>). Comparing the parallel YY vs. crossed XY, on the other hand, the phases should be the same except for any non-zero X vs. Y delays on the small antennas, plus the effect of <math>\xi_{rot}</math>. Thus, <math>\xi_{rot}</math> = 0 on XX and YY measurements, and non-zero for XY and YX measurements.

We can derive expressions by considering antenna-based phases on X polarization as <math>\phi(X_i) = \phi_i + \delta_{i14}\xi_{rot}</math> and on Y polarization as <math>\phi(Y_i) = \phi_i + d\phi_i + \delta_{i14}\xi_{rot}</math>, i.e. the Y phases are nominally the same as for X, except for a possible X-Y delay difference <math>\tau_i</math>, here written as delay phase <math>d\phi_i = 2\pi\tau_i f</math>. We are finding that this delay is a complicated function of frequency, so it is just as well to keep it in terms of phase. The <math>\xi_{rot}</math> term is only present on antenna 14, hence the use of the Kronecker <math>\delta</math>. As noted above, the term <math>\xi_{rot}</math> is zero if the antenna 14 feed is not rotated (i.e. for XX and YY measurements) and non-zero if it is (for XY and YX measurements). On a baseline <math>(i,j)</math>, then, the four polarization terms become:
<center><math>
\begin{align}
\phi_{ij}(XX) &= \phi(X_j) - \phi(X_i) = \phi_j - \phi_i\\
\phi_{ij}(XY) &= \phi(Y_j) - \phi(X_i) = \phi_j + d\phi_j + \delta_{j14}\xi_{rot} - \phi_i\\
\phi_{ij}(YX) &= \phi(X_j) - \phi(Y_i) = \phi_j + \delta_{j14}\xi_{rot} - \phi_i - d\phi_i\\
\phi_{ij}(YY) &= \phi(Y_j) - \phi(Y_i) = \phi_j + d\phi_j - \phi_i - d\phi_i
\end{align}\qquad\qquad (5)
</math></center>

We then examine the channel differences on baselines with antenna 14 (<math>j=14</math>), i.e.
<center><math>
\begin{align}
\phi_{i14}(XY) - \phi_{i14}(XX) &= \phi_{14} + d\phi_{14} + \xi_{rot} - \phi_i - \phi_{14} + \phi_i &= d\phi_{14} + \xi_{rot}, \\
\phi_{i14}(YY) - \phi_{i14}(YX) &= \phi_{14} + d\phi_{14} - \phi_i - d\phi_i - \phi_{14} - \xi_{rot} + \phi_i + d\phi_i &= d\phi_{14} - \xi_{rot}, \\
\phi_{i14}(XX) - \phi_{i14}(YX) &= \phi_{14} - \phi_i - \phi_{14} - \xi_{rot} + \phi_i + d\phi_i &= d\phi_i - \xi_{rot}, \\
\phi_{i14}(XY) - \phi_{i14}(YY) &= \phi_{14} + d\phi_{14} + \xi_{rot} - \phi_i - \phi_{14} - d\phi_{14} + \phi_i + d\phi_i &= d\phi_i + \xi_{rot}.
\end{align}
</math></center>
Consequently, we can solve redundantly in two ways for the antenna-based delay phases:
<center><math>
\begin{align}
d\phi_i &= \phi_{i14}(XX) - \phi_{i14}(YX) + \xi_{rot} = \phi_{i14}(XY) - \phi_{i14}(YY) - \xi_{rot}, \\
d\phi_{14} &= \phi_{i14}(XY) - \phi_{i14}(XX) - \xi_{rot} = \phi_{i14}(YY) - \phi_{i14}(YX) + \xi_{rot},
\end{align}\qquad\qquad (6)
</math></center>
where we specifically use <math>j=14</math> to emphasize that this quantity for all antennas should be the same value, because the measurements are all baselines with antenna 14. Both of these give the same expression:
<center><math>
2\xi_{rot} = \phi_{i14}(XY) - \phi_{i14}(YY) - \phi_{i14}(XX) + \phi_{i14}(YX),
</math></center>
which, when evaluated for the thirteen different measurements do indeed give the same result within statistical variations. Care must be taken to do an appropriate average to take care of the <math>2\pi</math> phase ambiguity. One way to do this is form unit vectors and sum them, then find the phase of the summed vector. In Python, the following expression calculates an average phase phi_avg from the 13 individual measurements phi, where the sum over index 0 is over antennas:
phi_avg = np.angle(np.sum(np.exp(1j*phi),0))

Once we have this average value of <math>\xi_{rot}</math>, the equations (6) give two measurements for each antenna for <math>d\phi_i</math>, and the 26 measurements for antenna 14 for <math>d\phi_{14}</math>, which can be averaged in the same manner.

'''Figure 1x''' shows the results for a measurement on 2017-07-02.

== Applying the Measurements ==
[[File: 20170702-amp-correction.png | thumb | 600px | '''Figure 2x:''' Amplitude vs frequency for channels XX, YY, XY and YX, on ants 1-13, before (green) and after (black) correction for feed rotation.]]
[[File: 20170702-phase-correction.png | thumb | 600px | '''Figure 3x:''' Phase vs frequency for channels XX, YY, XY and YX, on ants 1-13, before (green) and after (black) correction for feed rotation.]]

Once we have these, we can apply corrections to each of the polarization channels, and then do the feed rotation correction. The corrections are done to data taken in a normal way, without rotating the 27-m feed. The application of the correction is found by removing the effects of the delays and rotations in equation (5):
<center><math>
\begin{align}
\phi_{ij}(XX)' &= \phi_{ij}(XX),\quad\text{no correction} \\
\phi_{ij}(XY)' &= \phi_{ij}(XY) - d\phi_j - \delta_{j14}\xi_{rot}, \\
\phi_{ij}(YX)' &= \phi_{ij}(YX) + d\phi_i - \delta_{j14}\xi_{rot} + \pi, \\
\phi_{ij}(YY)' &= \phi_{ij}(YY) + d\phi_i - d\phi_j,
\end{align}\qquad (6)
</math></center>
where the third term has an offset of <math>\pi</math> because this term should be flipped for negative parallactic angle, i.e. should be <math>\phi_{ij}(YX) = \phi_j - \phi_i + \pi</math>. Again, the Kronecker <math>\delta</math> indicates the fact that this term is applied only for baselines involving antenna 14. After the corrections are applied, we have
<center><math>
\begin{align}
\phi_{ij}(XX)' &= \phi_j - \phi_i \\
\phi_{ij}(XY)' &= \phi_j - \phi_i, \\
\phi_{ij}(YX)' &= \phi_j - \phi_i + \pi, \\
\phi_{ij}(YY)' &= \phi_j - \phi_i.
\end{align}
</math></center>

I tried applying the feed rotation correction for data taken on 2017-07-02, and it does seem to work. '''Figures 2x''' and '''3x''' show the amplitude and phase on all baselines with Ant 14, with light green for data before correction and black for after correction. For ants 1-8 and 12, the XX and YY amplitudes have increased a bit, while the XY and YX amplitudes are much reduced. The corresponding phases are slightly improved in XX and YY, and noise-like for XY and YX (less so on YX for some antennas). For the other antennas, no correction was made since those feeds are already parallel to Ant 14.

The proof of this scheme will be seen when we observe a calibrator for many hours while the parallactic angle changes over HA, and then see that the amplitude time profiles become steady and well behaved.

Ultimately, the X-Y delays will need to be measured periodically (especially if the correlator is rebooted or X and Y delays are changed for other reasons), and then stored as a new calibration type in the SQL database.

== Comparison with the Mathematical Description in the Earlier Section ==
We now want to see how this compares with the mathematical development in the previous section. It turns out that they are the same, as long as we rewrite the expression <math>2\pi f\tau_i = \phi_i - \pi/2</math>. To see this, first write the corrections in equation (6) in matrix form:
<center><math>
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{in}
=
\begin{bmatrix}
\cos\Delta\chi & 0 & -\sin\Delta\chi & 0 \\
0 & \cos\Delta\chi & 0 & -\sin\Delta\chi \\
\sin\Delta\chi & 0 & \cos\Delta\chi & 0 \\
0 & \sin\Delta\chi & 0 & \cos\Delta\chi
\end{bmatrix}
\begin{bmatrix}
1 & 0 & 0 & 0 \\
0 & e^{-i(d\phi_j - \pi/2)} & 0 & 0 \\
0 & 0 & e^{i(d\phi_i - \pi/2)} & 0 \\
0 & 0 & 0 & e^{i(d\phi_i - d\phi_j)}
\end{bmatrix}
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{out}
</math></center>
where now this is the correction applied to the measured (<math>out</math>) data to covert it to the expected (<math>in</math>) data, and hence is the inverse of the matrix (2) in the previous section. Expanding the matrix product, this is
<center><math>
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{in}
=
\begin{bmatrix}
\cos\Delta\chi & 0 & -e^{i(d\phi_i - \pi/2)}\sin\Delta\chi & 0 \\
0 & e^{-i(d\phi_j - \pi/2)}\cos\Delta\chi & 0 & -e^{i(d\phi_i - d\phi_j)}\sin\Delta\chi \\
\sin\Delta\chi & 0 & e^{i(d\phi_i - \pi/2)}\cos\Delta\chi & 0 \\
0 & e^{-i(d\phi_j - \pi/2)}\sin\Delta\chi & 0 & e^{i(d\phi_i - d\phi_j)}\cos\Delta\chi
\end{bmatrix}
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{out}
</math></center>
and converting back to <math>\tau_i</math>, it becomes:
<center><math>
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{in}
=
\begin{bmatrix}
\cos\Delta\chi & 0 & -e^{2\pi if\tau_i}\sin\Delta\chi & 0 \\
0 & e^{-2\pi if\tau_j}\cos\Delta\chi & 0 & -e^{2\pi if(\tau_i-\tau_j)}\sin\Delta\chi \\
\sin\Delta\chi & 0 & e^{i2\pi f\tau_i}\cos\Delta\chi & 0 \\
0 & e^{-2\pi if\tau_j}\sin\Delta\chi & 0 & e^{2\pi if(\tau_i-\tau_j)}\cos\Delta\chi
\end{bmatrix}
\begin{bmatrix}
XX \\
XY \\
YX \\
YY
\end{bmatrix}_{out}\qquad\qquad (7)
</math></center>
which is precisely the inverse of (3).

= AzEl Antenna Axis Offset =

[[File:3C84_cos-el-rotation.png|right|thumb|300px|'''Fig. 9:''' Observations and simulation of amplitude and phase on 3C84 for baseline Ant 1-14, where a phase shift proportional to <math>{2\pi\over\lambda} \cos E</math> is applied. The agreement is reasonably good except for some curvature, which could be residual baseline error.]]

[[File:3C273_cos-el-rotation.png|right|thumb|300px|'''Fig. 10:''' Observations and simulation of amplitude and phase on 3C273 for baseline Ant 1-14, where a phase shift proportional to <math>{2\pi\over\lambda} \cos E</math> is applied. The agreement is reasonably good, except for some curvature at negative hour angle, which could be residual baseline error.]]

During our investigation of the parallactic angle correction, we noted a "V"-shaped dependence of phase on HA, for the AzEl baselines with Ant 14, that cannot be due to parallactic angle. Dr. Avinash Deshpande (Raman Research Institute, Bangalore -- ''Thanks to Dr. Ananthakrishnan for contacting him'') confirms that no phase rotation is expected for the parallactic correction, aside from the 180-degree phase jump at the meridian crossing. He suggests that a non-intersecting axis is the cause, and this was confirmed. He notes that the effect of non-intersecting axes is a phase rotation of

<center><math>{2\pi\over\lambda} d\cos E</math></center>

where <math>E</math> is the elevation angle, and <math>d</math> is the offset distance. As a test, I applied this function, using d = 11.5 cm (based on the apparent phase variation in the observed phases), and obtained the results in '''Figures 9 and 10'''. Although the observed phases show a bit more curvature than the simulation, this was found to be due to residual baseline errors.

=== Further update ===
[[File:3C84_cos-el-correction.png|left|thumb|300px|'''Fig. 11:''' Observations and phase-corrected observations for 3C84 taken on 2016-11-13, where d = 15.2 cm was applied. Shown are Ant 1-5 baselines with Ant 14. The remaining phase variations are consistent with a residual Bx baseline error.]]

On 2016 Nov 13, new observations of 3C84 were taken, and the correction for the axis offset (d = 15.2 cm) was applied, as shown in '''Figure 11''' (at left). It appears that this correction works well, and that there is a residual baseline error on each of the antennas due to the fact that they were originally determined without the axis-offset correction. --[[User:Dgary|Dgary]] ([[User talk:Dgary|talk]]) 14:20, 15 November 2016 (UTC)

This change was permanently instituted in DPP_PROCESS_STATEFRAME.f90 on 2016-11-16.

'''2025-06-03 NB:''' We have replaced the old antennas (9, 10, 11, and 13) with new antennas and added two more (14 and 15). Caius reports that the new antennas may have a shorted distance d ~ 14 cm. We'll have to measure the phase variation on calibrators and determine if those antennas need a different value of d.

Owens Valley Solar Arrays

2025-02-13T17:21:55Z

Dgary: /* EOVSA Publications */

[[File:Eovsa1.png|border|text-top|800px]]

<big>[http://ovsa.njit.edu/ EOVSA] (Expanded Owens Valley Solar Array) is a solar-dedicated radio interferometer operated by the New Jersey Institute of Technology and serving as a '''National Science Foundation Geospace Facility'''. [[File:NSF.jpg|70px]]
<pre>Operation of EOVSA is supported by the National Science Foundation under Grant No. AGS-2130832. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. </pre>
This wiki serves as the site for EOVSA documentation. </big>

[[File:OVRO-LWA1.png|border|text-top|800px]]

<big>OVRO-LWA (Owens Valley Radio Observatory Long Wavelength Array) is an all-sky imager that has a new solar-dedicated spectroscopic imaging mode. OVRO-LWA is a multi-institutional collaboration led by Caltech. NJIT Solar Radio Group is leading its solar-mode development and science. At the bottom of this page are new links for that facility. </big>

== EOVSA Flare List ==

* [https://ovsa.njit.edu/flarelist Query EOVSA Flare list]
* List of EOVSA flares in separate years: [[2025]], [[2024]], [[2023]], [[2022]], [[2021]], [[2020]], [[2019]], [[2017]]

== Using EOVSA Data ==
* <big>[[EOVSA Data Products]]</big>: An introduction to standard EOVSA spectrogram and spectral image products with example scripts for reading and plotting.
* <big>[[EOVSA Data Policy]]</big>: Policy for using EOVSA data products.
* <big>Analysis Software</big>: These are for in-depth use of EOVSA data (from calibrated visibilities) and tools for quantitative analysis.
** [https://github.com/suncasa/suncasa SunCASA] A wrapper around [https://casa.nrao.edu/ CASA (the Common Astronomy Software Applications package)] for synthesis imaging and visualizing solar spectral imaging data. CASA is one of the leading software tool for "supporting the data post-processing needs of the next generation of radio astronomical telescopes such as ALMA and VLA", an international effort led by the [https://public.nrao.edu/ National Radio Astronomy Observatory]. The current version of CASA uses Python (2.7) interface. More information about CASA can be found on [https://casa.nrao.edu/ NRAO's CASA website ]. Note, CASA is available ONLY on UNIX-BASED PLATFORMS (and therefore, so is SunCASA).
** [https://github.com/Gelu-Nita/GSFIT GSFIT] A IDL-widget(GUI)-based spectral fitting package called gsfit, which provides a user-friendly display of EOVSA image cubes and an interface to fast fitting codes (via platform-dependent shared-object libraries).
** [https://github.com/suncasa/pygsfit pyGSFIT] A Python-widget(pyQT)-based spectral fitting package, which provides a user-friendly display of EOVSA image cubes, spatially resolved spectra, and an interface to scipy-based fitting codes.
** [[Spectrogram Software]]
** [[Mapping Software]]
* <big>Data Analysis Guides (for those who start from raw data) </big>






**[[Tohban Guide to Self Calibration and Imaging for EOVSA]] Step-to-step guide for manually making images from raw visibility data.
**[[EOVSA flare pipeline]] Description of the EOVSA flare pipeline and tutorial for running it to produce quicklook images.



* <big>EOVSA Modeling Guide</big>
**[[GX Simulator]]

* Other helpful links
** [https://casaguides.nrao.edu CASA Guides]
** [http://www.lmsal.com/solarsoft/ SolarSoft IDL]
** [http://www.atnf.csiro.au/computing/software/miriad/userguide/userhtml.html Miriad Guides]
** [https://sites.google.com/site/fgscodes/ Fast Gyrosynchrotron Codes (Alexey Kuznetsov's website)]
** [[Basic GitHub Tutorial]]


* <big>[[Full Disk Simulations]]</big>
* <big>[[All-Day Synthesis Issues]]</big>
* <big>[[Analyzing Pre-2017 Data]]</big>
* <big>[[Fixing Pipeline Problems pre-2021-Feb-07]]</big>

== EOVSA Documentation ==

* <big>General</big>
** [[Downconversion and Frequency Tuning]]
** [[Dealing with Radio Frequency Interference]]
** [[Switching between 200 MHz and 300 MHz Correlator]]
** [[Observing in "Fast" Mode]]

* <big>Computer-Network</big>
** [[Computing Systems]]
** [[Network]]

* <big>Control System</big>
** [[27-m Antenna Commands]]
** [[Schedule Commands]]
** [[Control Commands]]
** [[Attenuation and Level Control]]

* <big>Hardware</big>
** [[Hardware Overview]]
** [[2.1-m Antennas]]
** [[27-m Antennas]]

* <big>System Software</big>
** [[Calibration Database]]
** [[Stateframe Database]]
** [[Database Maintenance]]
** [[Create CASA measurement sets]]

* <big>Calibration</big>
**[[Calibration Overview]]
**[[Pointing Calibration]]
**[[Total Power Calibration]]
**[[System Gain Calibration]]
**[[Antenna Position]] (Baseline Calibration)
**[[Reference Gain Calibration]]
**[[Daily Gain Calibration]]
**[[Delay Calibration]]
**[[Bandpass Calibration]]
**[[Polarization Calibration]]
**[[Calibrator Survey]]
**[[Practical Calibration Tutorial]]

* <big>[[Starburst]]</big>

== EOVSA System Software ==

* LabVIEW software
* Python code [https://github.com/dgary50/eovsa Github repository]
* [[Python3 Code Installation]]

== EOVSA Observing Log ==
[[2016 November]]; [[2016 December| December]]

[[2017 January]]; [[2017 February | February]]; [[2017 March | March]]; [[2017 April | April]]; [[2017 May | May]]; [[2017 June | June]];
[[2017 July | July]]; [[2017 August | August]]; [[2017 September | September]]; [[2017 October | October]]; [[2017 November | November]]; [[2017 December | December]]

[[2018 January]]; [[2018 February | February]]; [[2018 March | March]]; [[2018 April | April]]; [[2018 May | May]]; [[2018 June | June]];
[[2018 July | July]]; [[2018 August | August]]; [[2018 September | September]]; [[2018 October | October]]; [[2018 November | November]]; [[2018 December | December]]

[[2019 January]]; [[2019 February | February]]; [[2019 March | March]]; [[2019 April | April]]; [[2019 May | May]]; [[2019 June | June]];
[[2019 July | July]]; [[2019 August | August]]; [[2019 September | September]]; [[2019 October | October]]; [[2019 November | November]]; [[2019 December | December]]

[[2020 January]]; [[2020 February | February]]; [[2020 March | March]]; [[2020 April | April]]; [[2020 May | May]]; [[2020 June | June]];
[[2020 July | July]]; [[2020 August | August]]; [[2020 September | September]]; [[2020 October | October]]; [[2020 November | November]]; [[2020 December | December]]

[[2021 January]]; [[2021 February | February]]; [[2021 March | March]]; [[2021 April | April]]; [[2021 May | May]]; [[2021 June | June]];
[[2021 July | July]]; [[2021 August | August]]; [[2021 September | September]]; [[2021 October | October]]; [[2021 November | November]]; [[2021 December | December]]

[[2022 SQL Outage]]

[[2023 January]]; [[2023 February | February]]; [[2023 March | March]]; [[2023 April | April]]; [[2023 May | May]]; [[2023 June | June]];
[[2023 July | July]]; [[2023 August | August]]; [[2023 September | September]]; [[2023 October | October]]; [[2023 November | November]]; [[2023 December | December]]

[[2024 January]]; [[2024 February | February]]; [[2024 March | March]];[[2024 April | April]];[[2024 May |May]]; [[2024 June | June]]; [[2024 July | July]]; [[2024 August | August]];
[[2024 September | September]]; [[2024 October | October]]; [[2024 November | November]]; [[2024 December | December]]

[[2025 January]]; [[2025 February | February]]; [[2025 March | March]];[[2025 April | April]];[[2025 May |May]]; [[2025 June | June]]; [[2025 July | July]]; [[2025 August | August]];
[[2025 September | September]]; [[2025 October | October]]; [[2025 November | November]]; [[2025 December | December]]

== EOVSA Scientist on Duty ==
* Scientist on Duty (SoD): EOVSA team members take turns and serve as an SoD to work with our onsite observatory staff on day-to-day observing. They are also responsible for monitoring solar activities and ensuring that the data we collect are of high quality.
* SoD observing logs:
** 2024: [https://docs.google.com/document/d/1QDWw5y4HpcE7CSpzXwftMqQT4FDgNJj-6fRrgWrqdug/edit?usp=sharing May (and before that)], [https://docs.google.com/document/d/1Rh2gYBV2E454xVYEv8jx5IXKd1N2Z05ns4dhI2XCE08/edit?usp=sharing June], [https://docs.google.com/document/d/1beUpp6rgwjqSxKbuHzXIR9hhPrGyi0j-SjtEIeav9Vg/edit?usp=sharing July], [https://docs.google.com/document/d/1pSzUXW5gd-4cZAR-gglTUVM_J2UHMa4wYJ2AzD4cdEo/edit?usp=sharing August], [https://docs.google.com/document/d/18pArAP0kRDhXHbty_y3TtrygmWkC2oLn-UD7njIpRIo/edit?usp=sharing September], [https://docs.google.com/document/d/1Qt6vhrqPAOG7W5Y_tLiod_QgNR1FDyzRxQcg6_oJQd4/edit?usp=sharing October], [https://docs.google.com/document/d/1pv9-Wne80FCrg0J5BkjOafmof_s3jlnc9HwyzWkIBfU/edit?usp=sharing November], [https://docs.google.com/document/d/1O5svOVwQZbUON1GMR_8nBR5LAL0M8RM2_zWW4oeBiLk/edit?usp=sharing December]
** 2025: [https://docs.google.com/document/d/1pUdSRyWgQa2py1PSLa3CKs_DDqL_SOgx6MMIp4cPnpk/edit?usp=sharing January],[https://docs.google.com/document/d/18cnIAaeM8UBiYPtsQn7g6TM8mjr57blSoY9l-6ShhwQ/edit?usp=sharing February]
* SoD instructions:
** Daily routines: see [https://docs.google.com/document/d/1_iGnMRRrvb85Z0vT8-LzgQmCOKDSATEuQ0vTsn2C-dc/edit?usp=sharing SoD Routines] for detailed instructions.
** Instructions for [[making quick-look flare spectrograms and movies]]

==OVRO-LWA Solar-Dedicated Spectroscopic Imager==
The OVRO-LWA (Owens Valley Radio Observatory Long Wavelength Array) has recently been upgraded to include a solar-dedicated beam and two solar imaging modes (slow visibilities of 352 antennas with a 10-s cadence, and fast visibilities of 48 antennas with a 0.1-s cadence). The large collecting area and excellent calibration provide unprecedented high-sensitivity imaging of the quiet Sun and bursts. The array is currently in commissioning and observations are not yet continuous, but they are becoming more so. See the daily realtime data at http://ovsa.njit.edu/status.php for '''real-time display of the spectrogram and a selection of images''', both updated on a 1-min cadence.

===Solar-Dedicated Modes===
* Beamformer: the beamformer uses the 256 core antennas to form a synthesized beam of more than 1 degree in size that tracks the Sun from sunrise to sunset. This permits a continuous record of the full-Stokes total flux (without spatial resolution) of the Sun (a dynamic spectrum) with 24 kHz frequency resolution (3072 frequencies from 15-90 MHz) and as low as 1 ms time resolution.

* Slow Visibility Imaging: in this mode, the entire 352-element array is interferometrically correlated to provide visibilities for imaging at all 3072 frequencies at 10-s time resolution. This is ideal for imaging quiet Sun and slowly-varying emission such as coronal mass ejections and active region variability.

* Fast Visibility Imaging: in this mode, a subset of 48 antennas (chosen to include mainly outer antennas to maintain good spatial resolution) is interferometrically correlated to provide visibilities for imaging at 768 frequencies (96 kHz frequency resolution) at 0.1-s time resolution. This is ideal for imaging rapidly varying emission such as type II and type III bursts as well as many other solar spectral fine structures.

===Inital Data Access===
In its current commissioning state, we try to run the beamformer and imaging pipeline every day in real-time since November 2023 (no latency for beamforming spectrograms and 5-10 min latency for images). Quicklook real-time spectrograms/images can be accessed from http://ovsa.njit.edu/status.php. To access data from previous days, use the following links (replace yyyymmdd with the date you desire):
* Quicklook beamformer total-power spectrograms: http://ovsa.njit.edu/lwa-data/1min_spectra/yyyymmdd/. Check this link for additional daily plots [[Daily OVRO-LWA Beamformer Data]].
* Quicklook multi-frequency movies at 1-min cadence: http://ovsa.njit.edu/lwa-data/1min_images/yyyymmdd/movie_yyyy-mm-dd.html

Note our pipeline processing development is still in the early phase. For example, absolute flux calibrations have not been done for the beamformer spectrograms. Also, artificial effects (including ionospheric refraction effects) are present in the images that cause distortions/shifts. We caution interested users only to consider them for quick-look purposes at this point. Please contact the EOVSA PIs (Dale Gary, Bin Chen) if you intend to use them for science.

===OVRO-LWA Operation Notes===

[[OVRO-LWA Operation Notes]]

== Tohbans ==

[[Trouble Shooting Guide]]

[[Tohban Records]]

[[Owen's Notes]]

[[Caius' Notes]]

[[Tohban EOVSA Imaging Tutorial A-Z]]

[[Tohban OVRO-LWA Imaging Tutorial]]

[[Tohban Guide to Self Calibration and Imaging for EOVSA]]

[[Guide to Upgrade SolarSoft(SSW)]]

== EOVSA Publications ==
Here is a (partial) list of publications that utilize EOVSA data. See also the collection of EOVSA publications at [https://ui.adsabs.harvard.edu/public-libraries/eQ7HfPkySqydu-B8BCt6QQ this NASA/ADS Library].
; 2025
: Lesovoi, S.V., Gary, D.E., Globa, M.V., Ivanov, E.F. (2025), Solar Physics 300, 23. [https://doi.org/10.1007/s11207-025-02433-z "On a Possible Scenario of Solar Coherent Bursts"]
: Xu, Y., Wang, M., Cao, A., Ji, K., Yurchyshyn, V., Qiu, J., Yu, S., Shen, J., & Cao, W. (2025), The Astrophysical Journal Letters, 979, L43. [https://iopscience.iop.org/article/10.3847/2041-8213/ada9e4 "High-resolution Observations of an X-1.0 White-light Flare with Moving Flare Ribbons"]

; 2024
: Collier, H., Hayes, L. A., Yu, S., Battaglia, A. F., Ashfield, W., Polito, V., Harra, L. K., & Krucker, S. (2024), arXiv e-prints, arXiv:2402.10546. [https://ui.adsabs.harvard.edu/abs/2024arXiv240210546C “Localising pulsations in the hard X-ray and microwave emission of an X-class flare”]
: Saqri, J., Veronig, A. M., Battaglia, A. F., Dickson, E. C. M., Gary, D. E., & Krucker, S. (2024), Astronomy and Astrophysics, 683, A41. [https://ui.adsabs.harvard.edu/abs/2024A&A...683A..41S "Efficiency of solar microflares in accelerating electrons when rooted in a sunspot"]
; 2023
: Tan, B., Yan, Y., Huang, J., Zhang, Y., Tan, C., & Zhu, X. (2023), Advances in Space Research, 72, 5563. [https://ui.adsabs.harvard.edu/abs/2023AdSpR..72.5563T "The physics of solar spectral imaging observations in dm-cm wavelengths and the application on space weather"]

: Li, D., Li, Z., Shi, F., Su, Y., Chen, W., Yu, F., Li, C., Qiu, Y., Huang, Y., & Ning, Z. (2023), Astronomy and Astrophysics, 680, L15. [https://ui.adsabs.harvard.edu/abs/2023A&A...680L..15L "Observational signature of continuously operating drivers of decayless kink oscillation"]

: Wang, M., Chen, B., Yu, S., Gary, D. E., Lee, J., Wang, H., & Cohen, C. (2023), The Astrophysical Journal, 954, 32. [https://ui.adsabs.harvard.edu/abs/2023ApJ...954...32W "The Solar Origin of an In Situ Type III Radio Burst Event"]

: Gary, D. E. (2023), Annual Review of Astronomy and Astrophysics, 61, 427. [https://ui.adsabs.harvard.edu/abs/2023ARA&A..61..427G "New Insights from Imaging Spectroscopy of Solar Radio Emission"]

: Nita, G. M., Fleishman, G. D., Kuznetsov, A. A., Anfinogentov, S. A., Stupishin, A. G., Kontar, E. P., Schonfeld, S. J., Klimchuk, J. A., & Gary, D. E. (2023), The Astrophysical Journal Supplement Series, 267, 6. [https://ui.adsabs.harvard.edu/abs/2023ApJS..267....6N "Data-constrained Solar Modeling with GX Simulator"]

: Song, D.-C., Tian, J., Li, Y., Ding, M. D., Su, Y., Yu, S., Hong, J., Qiu, Y., Rao, S., Liu, X., Li, Q., Chen, X., Li, C., & Fang, C. (2023), The Astrophysical Journal, 952, L6. [https://ui.adsabs.harvard.edu/abs/2023ApJ...952L...6S "Spectral Observations and Modeling of a Solar White-light Flare Observed by CHASE"]

: Mondal, S., Chen, B., & Yu, S. (2023), The Astrophysical Journal, 949, 56. [https://ui.adsabs.harvard.edu/abs/2023ApJ...949...56M "Multifrequency Microwave Imaging of Weak Transients from the Quiet Solar Corona"]

: Kontar, E. P., Emslie, A. G., Motorina, G. G., & Dennis, B. R. (2023), The Astrophysical Journal, 947, L13. [https://ui.adsabs.harvard.edu/abs/2023ApJ...947L..13K "The Efficiency of Electron Acceleration during the Impulsive Phase of a Solar Flare"]

: Saqri, J., Veronig, A. M., Dickson, E. C. M., Podladchikova, T., Warmuth, A., Xiao, H., Gary, D. E., Battaglia, A. F., & Krucker, S. (2023), Astronomy and Astrophysics, 672, A23. [https://ui.adsabs.harvard.edu/abs/2023A&A...672A..23S "Multi-point study of the energy release and impulsive CME dynamics in an eruptive C7 flare"]
; 2022

: Kou, Y., Cheng, X., Wang, Y., Yu, S., Chen, B., Kontar, E. P., & Ding, M. (2022), Nature Communications, 13, 7680. [https://ui.adsabs.harvard.edu/abs/2022NatCo..13.7680K "Microwave imaging of quasi-periodic pulsations at flare current sheet"]

: Chertok, I. M. (2022), Monthly Notices of the Royal Astronomical Society, 517, 2709. [https://ui.adsabs.harvard.edu/abs/2022MNRAS.517.2709C "On some features of the solar proton event on 2021 October 28 - GLE73"]

: Lörinčík, J., Polito, V., De Pontieu, B., Yu, S., & Freij, N. (2022), Frontiers in Astronomy and Space Sciences, 9, 334. [https://ui.adsabs.harvard.edu/abs/2022FrASS...940945L "Rapid variations of Si IV spectra in a flare observed by interface region imaging spectrograph at a sub-second cadence"]

: Klein, K.-L., Musset, S., Vilmer, N., Briand, C., Krucker, S., Francesco Battaglia, A., Dresing, N., Palmroos, C., & Gary, D. E. (2022), Astronomy and Astrophysics, 663, A173. [https://ui.adsabs.harvard.edu/abs/2022A&A...663A.173K "The relativistic solar particle event on 28 October 2021: Evidence of particle acceleration within and escape from the solar corona"]

: Fleishman, G. D., Nita, G. M., Chen, B., Yu, S., & Gary, D. E. (2022), Nature, 606, 674. [https://ui.adsabs.harvard.edu/abs/2022Natur.606..674F "Solar flare accelerates nearly all electrons in a large coronal volume"]

: Li, X., Guo, F., Chen, B., Shen, C., & Glesener, L. (2022), The Astrophysical Journal, 932, 92. [https://ui.adsabs.harvard.edu/abs/2022ApJ...932...92L "Modeling Electron Acceleration and Transport in the Early Impulsive Phase of the 2017 September 10th Solar Flare"]

: Zhang, J., Chen, B., Yu, S., Tian, H., Wei, Y., Chen, H., Tan, G., Luo, Y., & Chen, X. (2022), The Astrophysical Journal, 932, 53. [https://ui.adsabs.harvard.edu/abs/2022ApJ...932...53Z "Implications for Additional Plasma Heating Driving the Extreme-ultraviolet Late Phase of a Solar Flare with Microwave Imaging Spectroscopy"]

: Liu, N., Jing, J., Xu, Y., & Wang, H. (2022), The Astrophysical Journal, 930, 154. [https://ui.adsabs.harvard.edu/abs/2022ApJ...930..154L "Multi-instrument Comparative Study of Temperature, Number Density, and Emission Measure during the Precursor Phase of a Solar Flare"]

: López, F. M., Giménez de Castro, C. G., Mandrini, C. H., Simões, P. J. A., Cristiani, G. D., Gary, D. E., Francile, C., & Démoulin, P. (2022), Astronomy and Astrophysics, 657, A51. [https://ui.adsabs.harvard.edu/abs/2022A&A...657A..51L "A solar flare driven by thermal conduction observed in mid-infrared"]

: Unverferth, J., & Longcope, D. (2021), The Astrophysical Journal, 923, 248. [https://ui.adsabs.harvard.edu/abs/2021ApJ...923..248U "Examining Flux Tube Interactions as a Cause of Sub-alfvénic Outflow"]
;2021

: Wei, Y., Chen, B., Yu, S., Wang, H., Jing, J., & Gary, D. E. (2021), The Astrophysical Journal, 923, 213. [https://ui.adsabs.harvard.edu/abs/2021ApJ...923..213W "Coronal Magnetic Field Measurements along a Partially Erupting Filament in a Solar Flare"]

: Jing, J., Inoue, S., Lee, J., Li, Q., Nita, G. M., Xu, Y., Liu, C., Gary, D. E., & Wang, H. (2021), The Astrophysical Journal, 922, 108. [https://ui.adsabs.harvard.edu/abs/2021ApJ...922..108J "Understanding the Initiation of the M2.4 Flare on 2017 July 14"]

: Battaglia, A. F., Saqri, J., Massa, P., Perracchione, E., Dickson, E. C. M., Xiao, H., Veronig, A. M., Warmuth, A., Battaglia, M., Hurford, G. J., Meuris, A., Limousin, O., Etesi, L., Maloney, S. A., Schwartz, R. A., Kuhar, M., Schuller, F., Senthamizh Pavai, V., Musset, S., Ryan, D. F., Kleint, L., Piana, M., Massone, A. M., Benvenuto, F., Sylwester, J., Litwicka, M., Stȩślicki, M., Mrozek, T., Vilmer, N., Fárník, F., Kašparová, J., Mann, G., Gallagher, P. T., Dennis, B. R., Csillaghy, A., Benz, A. O., & Krucker, S. (2021), Astronomy and Astrophysics, 656, A4. [https://ui.adsabs.harvard.edu/abs/2021A&A...656A...4B "STIX X-ray microflare observations during the Solar Orbiter commissioning phase"]

: Shaik, S. B., & Gary, D. E. (2021), The Astrophysical Journal, 919, 44. [https://ui.adsabs.harvard.edu/abs/2021ApJ...919...44S "Implications of Flat Optically Thick Microwave Spectra in Solar Flares for Source Size and Morphology"]

: Kocharov, L., Omodei, N., Mishev, A., Pesce-Rollins, M., Longo, F., Yu, S., Gary, D. E., Vainio, R., & Usoskin, I. (2021), The Astrophysical Journal, 915, 12. [https://ui.adsabs.harvard.edu/abs/2021ApJ...915...12K "Multiple Sources of Solar High-energy Protons"]

: Chen, B., Battaglia, M., Krucker, S., Reeves, K. K., & Glesener, L. (2021), The Astrophysical Journal, 908, L55. [https://ui.adsabs.harvard.edu/abs/2021ApJ...908L..55C "Energetic Electron Distribution of the Coronal Acceleration Region: First Results from Joint Microwave and Hard X-Ray Imaging Spectroscopy"]

: Chhabra, S., Gary, D. E., Hallinan, G., Anderson, M. M., Chen, B., Greenhill, L. J., & Price, D. C. (2021), The Astrophysical Journal, 906, 132. [https://ui.adsabs.harvard.edu/abs/2021ApJ...906..132C "Imaging Spectroscopy of CME-associated Solar Radio Bursts using OVRO-LWA"]
;2020 and earlier

: Reeves, K. K., Polito, V., Chen, B., Galan, G., Yu, S., Liu, W., & Li, G. (2020), The Astrophysical Journal, 905, 165. [https://ui.adsabs.harvard.edu/abs/2020ApJ...905..165R "Hot Plasma Flows and Oscillations in the Loop-top Region During the 2017 September 10 X8.2 Solar Flare"]

: Nindos, A. (2020), Frontiers in Astronomy and Space Sciences, 7, 57. [https://ui.adsabs.harvard.edu/abs/2020FrASS...7...57N "Incoherent Solar Radio Emission"]

: Yu, S., Chen, B., Reeves, K. K., Gary, D. E., Musset, S., Fleishman, G. D., Nita, G. M., & Glesener, L. (2020), The Astrophysical Journal, 900, 17. [https://ui.adsabs.harvard.edu/abs/2020ApJ...900...17Y "Magnetic Reconnection during the Post-impulsive Phase of a Long-duration Solar Flare: Bidirectional Outflows as a Cause of Microwave and X-Ray Bursts"]

: Chen, B., Yu, S., Reeves, K. K., & Gary, D. E. (2020), The Astrophysical Journal, 895, L50. [https://ui.adsabs.harvard.edu/abs/2020ApJ...895L..50C "Microwave Spectral Imaging of an Erupting Magnetic Flux Rope: Implications for the Standard Solar Flare Model in Three Dimensions"]

: Kuroda, N., Fleishman, G. D., Gary, D. E., Nita, G. M., Chen, B., & Yu, S. (2020), Frontiers in Astronomy and Space Sciences, 7, 22. [https://ui.adsabs.harvard.edu/abs/2020FrASS...7...22K "Evolution of Flare-accelerated Electrons Quantified by Spatially Resolved Analysis"]

: Glesener, L., Krucker, S., Duncan, J., Hannah, I. G., Grefenstette, B. W., Chen, B., Smith, D. M., White, S. M., & Hudson, H. (2020), The Astrophysical Journal, 891, L34. [https://ui.adsabs.harvard.edu/abs/2020ApJ...891L..34G "Accelerated Electrons Observed Down to <7 keV in a NuSTAR Solar Microflare"]

: Karlický, M., Chen, B., Gary, D. E., Kašparová, J., & Rybák, J. (2020), The Astrophysical Journal, 889, 72. [https://ui.adsabs.harvard.edu/abs/2020ApJ...889...72K "Drifting Pulsation Structure at the Very Beginning of the 2017 September 10 Limb Flare"]

: Fleishman, G. D., Gary, D. E., Chen, B., Kuroda, N., Yu, S., & Nita, G. M. (2020), Science, 367, 278. [https://ui.adsabs.harvard.edu/abs/2020Sci...367..278F "Decay of the coronal magnetic field can release sufficient energy to power a solar flare"]

: Chen, B., Shen, C., Gary, D. E., Reeves, K. K., Fleishman, G. D., Yu, S., Guo, F., Krucker, S., Lin, J., Nita, G. M., & Kong, X. (2020), Nature Astronomy, 4, 1140. [https://ui.adsabs.harvard.edu/abs/2020NatAs...4.1140C "Measurement of magnetic field and relativistic electrons along a solar flare current sheet"]

: Lee, J. (2018), Journal of Astronomy and Space Sciences, 35, 211. [https://ui.adsabs.harvard.edu/abs/2018JASS...35..211L "Analysis of Solar Microwave Burst Spectrum, I. Nonuniform Magnetic Field"]

: Gary, D. E., Bastian, T. S., Chen, B., Fleishman, G. D., & Glesener, L. (2018), Science with a Next Generation Very Large Array, 517, 99. [https://ui.adsabs.harvard.edu/abs/2018ASPC..517...99G "Radio Observations of Solar Flares"]

: Polito, V., Dudík, J., Kašparová, J., Dzifčáková, E., Reeves, K. K., Testa, P., & Chen, B. (2018), The Astrophysical Journal, 864, 63. [https://ui.adsabs.harvard.edu/abs/2018ApJ...864...63P "Broad Non-Gaussian Fe XXIV Line Profiles in the Impulsive Phase of the 2017 September 10 X8.3-class Flare Observed by Hinode/EIS"]

: Gary, D. E., Chen, B., Dennis, B. R., Fleishman, G. D., Hurford, G. J., Krucker, S., McTiernan, J. M., Nita, G. M., Shih, A. Y., White, S. M., & Yu, S. (2018), The Astrophysical Journal, 863, 83. [https://ui.adsabs.harvard.edu/abs/2018ApJ...863...83G "Microwave and Hard X-Ray Observations of the 2017 September 10 Solar Limb Flare"]

: Fleishman, G. D., Nita, G. M., Kuroda, N., Jia, S., Tong, K., Wen, R. R., & Zhizhuo, Z. (2018), The Astrophysical Journal, 859, 17. [https://ui.adsabs.harvard.edu/abs/2018ApJ...859...17F "Revealing the Evolution of Non-thermal Electrons in Solar Flares Using 3D Modeling"]

: Kuroda, N., Gary, D. E., Wang, H., Fleishman, G. D., Nita, G. M., & Jing, J. (2018), The Astrophysical Journal, 852, 32. [https://ui.adsabs.harvard.edu/abs/2018ApJ...852...32K "Three-dimensional Forward-fit Modeling of the Hard X-Ray and Microwave Emissions of the 2015 June 22 M6.5 Flare"]

: Wang, H., Liu, C., Ahn, K., Xu, Y., Jing, J., Deng, N., Huang, N., Liu, R., Kusano, K., Fleishman, G. D., Gary, D. E., & Cao, W. (2017), Nature Astronomy, 1, 0085. [https://ui.adsabs.harvard.edu/abs/2017NatAs...1E..85W "High-resolution observations of flare precursors in the low solar atmosphere"]

: Nita, G. M., Hickish, J., MacMahon, D., & Gary, D. E. (2016), Journal of Astronomical Instrumentation, 5, 1641009-7366. [https://ui.adsabs.harvard.edu/abs/2016JAI.....541009N "EOVSA Implementation of a Spectral Kurtosis Correlator for Transient Detection and Classification"]

: Nita, G. M., & Gary, D. E. (2016), Journal of Geophysical Research (Space Physics), 121, 7353. [https://ui.adsabs.harvard.edu/abs/2016JGRA..121.7353N "Measurement of duration and signal-to-noise ratio of astronomical transients using a Spectral Kurtosis spectrometer"]

: Wang, Z., Gary, D. E., Fleishman, G. D., & White, S. M. (2015), The Astrophysical Journal, 805, 93. [https://ui.adsabs.harvard.edu/abs/2015ApJ...805...93W "Coronal Magnetography of a Simulated Solar Active Region from Microwave Imaging Spectropolarimetry"]

: Gary, D. E., Fleishman, G. D., & Nita, G. M. (2013), Solar Physics, 288, 549. [https://ui.adsabs.harvard.edu/abs/2013SoPh..288..549G "Magnetography of Solar Flaring Loops with Microwave Imaging Spectropolarimetry"]

== VLA Flare List and Publications ==
See [http://www.ovsa.njit.edu/wiki/index.php/VLA_Data_Survey#List_of_Jansky_VLA_Solar_Observations this link] for a list of flare observations made by the [https://science.nrao.edu/facilities/vla/ Karl G. Jansky Very Large Array] (VLA). Below is a partial list of publications that utilize VLA solar data (see also [https://ui.adsabs.harvard.edu/public-libraries/ZwbjpLo9RS-viufWEoQ95Q this NASA/ADS Library]).
* [https://ui.adsabs.harvard.edu/abs/2022ApJ...940..137L/abstract Luo et al. (2022), ApJ, 940, 137] ''Multiple Regions of Nonthermal Quasiperiodic Pulsations during the Impulsive Phase of a Solar Flare''
* [https://ui.adsabs.harvard.edu/abs/2021ApJ...922..134B/abstract Battaglia et al. (2021), ApJ, 922, 134] ''Multiple Electron Acceleration Instances during a Series of Solar Microflares Observed Simultaneously at X-Rays and Microwaves''
* [https://ui.adsabs.harvard.edu/abs/2021ApJ...911....4L/abstract Luo et al. (2021), ApJ, 911, 4] ''Radio Spectral Imaging of an M8.4 Eruptive Solar Flare: Possible Evidence of a Termination Shock''
* [https://ui.adsabs.harvard.edu/abs/2021ApJ...910...40Z/abstract Zhang et al. (2021), ApJ, 910, 40] ''Multiwavelength Observations of the Formation and Eruption of a Complex Filament''
* [https://ui.adsabs.harvard.edu/abs/2020ApJ...904...94S/abstract Sharma et al. (2020), ApJ, 904, 94] ''Radio and X-Ray Observations of Short-lived Episodes of Electron Acceleration in a Solar Microflare''
* [https://ui.adsabs.harvard.edu/abs/2019ApJ...884...63C/abstract Chen et al. (2019), ApJ, 884, 63] ''Radio Spectroscopic Imaging of a Solar Flare Termination Shock: Split-band Feature as Evidence for Shock Compression''
* [https://ui.adsabs.harvard.edu/abs/2019ApJ...872...71Y/abstract Yu & Chen (2019), ApJ, 872, 71] ''Possible Detection of Subsecond-period Propagating Magnetohydrodynamics Waves in Post-reconnection Magnetic Loops during a Two-ribbon Solar Flare''
* [https://ui.adsabs.harvard.edu/abs/2018ApJ...866...62C/abstract Chen et al. (2018), ApJ, 866, 62] ''Magnetic Reconnection Null Points as the Origin of Semirelativistic Electron Beams in a Solar Jet
''
* [https://ui.adsabs.harvard.edu/abs/2017ApJ...848...77W/abstract Wang et al. (2016), ApJ, 848, 77] ''Dynamic Spectral Imaging of Decimetric Fiber Bursts in an Eruptive Solar Flare''
* [https://ui.adsabs.harvard.edu/abs/2015Sci...350.1238C/abstract Chen et al. (2015), Science, 350, 1238] ''Particle acceleration by a solar flare termination shock''
* [https://ui.adsabs.harvard.edu/abs/2014ApJ...794..149C/abstract Chen et al. (2014), ApJ, 794, 149] ''Direct Evidence of an Eruptive, Filament-hosting Magnetic Flux Rope Leading to a Fast Solar Coronal Mass Ejection''
* [https://ui.adsabs.harvard.edu/abs/2013ApJ...763L..21C/abstract Chen et al. (2013), ApJL, 763, 21] ''Tracing Electron Beams in the Sun's Corona with Radio Dynamic Imaging Spectroscopy''

==Radio Data from Around The Heliosphere==
* [http://ovsa.njit.edu//wiki/index.php/Radio_Data_from_Around_the_World#Radio_Data_Access '' Radio Data '']

2025

2025-01-04T18:39:12Z

Dgary: /* List of EOVSA Flares with Spectrogram Data */

== List of EOVSA Flares with Spectrogram Data ==

===January===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Position || TP Spectrogram || XP Spectrogram || STIX Coverage || AIA Movie || EOVSA Images || Comments
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2025-01-03 2025-01-03] || 22:38 || X1.1 || || [[File:eovsa.spec_tp.flare_id_202501032238.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2025/eovsa.spec_tp.flare_id_202501032238.fits download FITS] || [[File:eovsa.spec_xp.flare_id_202501032238.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2025/eovsa.spec_xp.flare_id_202501032238.fits download FITS] || Yes || || ||
|-
|}

2025

2025-01-04T18:37:52Z

Dgary: /* January */

File:Eovsa.spec xp.flare id 202501032238.png

2025-01-04T18:36:28Z

Dgary:

File:Eovsa.spec tp.flare id 202501032238.png

2025-01-04T18:35:59Z

Dgary:

2025

2025-01-04T18:34:40Z

Dgary: /* List of EOVSA Flares with Spectrogram Data */

== List of EOVSA Flares with Spectrogram Data ==

===January===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Position || Spectrogram || STIX Coverage || AIA Movie || EOVSA Images || Comments
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2025-01-03 2025-01-03] || 22:38 || X1.1 || || [[File:eovsa.spec_tp.flare_id_202501032238.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2025/eovsa.spec_tp.flare_id_202501032238.fits download FITS] || [[File:eovsa.spec_xp.flare_id_202501032238.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2025/eovsa.spec_xp.flare_id_202501032238.fits download FITS] || Yes || || ||
|-
}

2025

2025-01-04T17:38:06Z

Dgary: Created page with "== List of EOVSA Flares with Spectrogram Data == ===January=== {| class="wikitable" ! Date || Time (UT) || GOES Class || Position || Spectrogram || STIX Coverage || AIA Movie || EOVSA Images || Comments |- | [http://ovsa.njit.edu/browser/?suntoday_date=2024-01-02 2024-01-02] || 18:10 || M1.2 || N05 E58 || 100px| [http://ovsa.njit.edu/events/2024/eovsa.spec.flare_id_20240102181000.fits plot data] || [https://datacente..."

== List of EOVSA Flares with Spectrogram Data ==

===January===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Position || Spectrogram || STIX Coverage || AIA Movie || EOVSA Images || Comments
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-01-02 2024-01-02] || 18:10 || M1.2 || N05 E58 || [[File:EOVSA_20240102_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/eovsa.spec.flare_id_20240102181000.fits plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1704218403&span=5396 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240102_1802 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2024/01/02/eovsa.lev1_mbd_12s.flare_id_20240102181000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2024/01/02/20240102181000/ FITS Files]
|-
}

Owens Valley Solar Arrays

2025-01-04T17:36:35Z

Dgary: /* EOVSA Flare List */

[[File:Eovsa1.png|border|text-top|800px]]

<big>[http://ovsa.njit.edu/ EOVSA] (Expanded Owens Valley Solar Array) is a solar-dedicated radio interferometer operated by the New Jersey Institute of Technology and serving as a '''National Science Foundation Geospace Facility'''. [[File:NSF.jpg|70px]]
<pre>Operation of EOVSA is supported by the National Science Foundation under Grant No. AGS-2130832. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. </pre>
This wiki serves as the site for EOVSA documentation. </big>

[[File:OVRO-LWA1.png|border|text-top|800px]]

<big>OVRO-LWA (Owens Valley Radio Observatory Long Wavelength Array) is an all-sky imager that has a new solar-dedicated spectroscopic imaging mode. OVRO-LWA is a multi-institutional collaboration led by Caltech. NJIT Solar Radio Group is leading its solar-mode development and science. At the bottom of this page are new links for that facility. </big>

== EOVSA Flare List ==

* [https://ovsa.njit.edu/flarelist Query EOVSA Flare list]
* List of EOVSA flares in separate years: [[2025]], [[2024]], [[2023]], [[2022]], [[2021]], [[2020]], [[2019]], [[2017]]

== Using EOVSA Data ==
* <big>[[EOVSA Data Products]]</big>: An introduction to standard EOVSA spectrogram and spectral image products with example scripts for reading and plotting.
* <big>[[EOVSA Data Policy]]</big>: Policy for using EOVSA data products.
* <big>Analysis Software</big>: These are for in-depth use of EOVSA data (from calibrated visibilities) and tools for quantitative analysis.
** [https://github.com/suncasa/suncasa SunCASA] A wrapper around [https://casa.nrao.edu/ CASA (the Common Astronomy Software Applications package)] for synthesis imaging and visualizing solar spectral imaging data. CASA is one of the leading software tool for "supporting the data post-processing needs of the next generation of radio astronomical telescopes such as ALMA and VLA", an international effort led by the [https://public.nrao.edu/ National Radio Astronomy Observatory]. The current version of CASA uses Python (2.7) interface. More information about CASA can be found on [https://casa.nrao.edu/ NRAO's CASA website ]. Note, CASA is available ONLY on UNIX-BASED PLATFORMS (and therefore, so is SunCASA).
** [https://github.com/Gelu-Nita/GSFIT GSFIT] A IDL-widget(GUI)-based spectral fitting package called gsfit, which provides a user-friendly display of EOVSA image cubes and an interface to fast fitting codes (via platform-dependent shared-object libraries).
** [https://github.com/suncasa/pygsfit pyGSFIT] A Python-widget(pyQT)-based spectral fitting package, which provides a user-friendly display of EOVSA image cubes, spatially resolved spectra, and an interface to scipy-based fitting codes.
** [[Spectrogram Software]]
** [[Mapping Software]]
* <big>Data Analysis Guides (for those who start from raw data) </big>






**[[Tohban Guide to Self Calibration and Imaging for EOVSA]] Step-to-step guide for manually making images from raw visibility data.
**[[EOVSA flare pipeline]] Description of the EOVSA flare pipeline and tutorial for running it to produce quicklook images.



* <big>EOVSA Modeling Guide</big>
**[[GX Simulator]]

* Other helpful links
** [https://casaguides.nrao.edu CASA Guides]
** [http://www.lmsal.com/solarsoft/ SolarSoft IDL]
** [http://www.atnf.csiro.au/computing/software/miriad/userguide/userhtml.html Miriad Guides]
** [https://sites.google.com/site/fgscodes/ Fast Gyrosynchrotron Codes (Alexey Kuznetsov's website)]
** [[Basic GitHub Tutorial]]


* <big>[[Full Disk Simulations]]</big>
* <big>[[All-Day Synthesis Issues]]</big>
* <big>[[Analyzing Pre-2017 Data]]</big>
* <big>[[Fixing Pipeline Problems pre-2021-Feb-07]]</big>

== EOVSA Documentation ==

* <big>General</big>
** [[Downconversion and Frequency Tuning]]
** [[Dealing with Radio Frequency Interference]]
** [[Switching between 200 MHz and 300 MHz Correlator]]
** [[Observing in "Fast" Mode]]

* <big>Computer-Network</big>
** [[Computing Systems]]
** [[Network]]

* <big>Control System</big>
** [[27-m Antenna Commands]]
** [[Schedule Commands]]
** [[Control Commands]]
** [[Attenuation and Level Control]]

* <big>Hardware</big>
** [[Hardware Overview]]
** [[2.1-m Antennas]]
** [[27-m Antennas]]

* <big>System Software</big>
** [[Calibration Database]]
** [[Stateframe Database]]
** [[Database Maintenance]]
** [[Create CASA measurement sets]]

* <big>Calibration</big>
**[[Calibration Overview]]
**[[Pointing Calibration]]
**[[Total Power Calibration]]
**[[System Gain Calibration]]
**[[Antenna Position]] (Baseline Calibration)
**[[Reference Gain Calibration]]
**[[Daily Gain Calibration]]
**[[Delay Calibration]]
**[[Bandpass Calibration]]
**[[Polarization Calibration]]
**[[Calibrator Survey]]
**[[Practical Calibration Tutorial]]

* <big>[[Starburst]]</big>

== EOVSA System Software ==

* LabVIEW software
* Python code [https://github.com/dgary50/eovsa Github repository]
* [[Python3 Code Installation]]

== EOVSA Observing Log ==
[[2016 November]]; [[2016 December| December]]

[[2017 January]]; [[2017 February | February]]; [[2017 March | March]]; [[2017 April | April]]; [[2017 May | May]]; [[2017 June | June]];
[[2017 July | July]]; [[2017 August | August]]; [[2017 September | September]]; [[2017 October | October]]; [[2017 November | November]]; [[2017 December | December]]

[[2018 January]]; [[2018 February | February]]; [[2018 March | March]]; [[2018 April | April]]; [[2018 May | May]]; [[2018 June | June]];
[[2018 July | July]]; [[2018 August | August]]; [[2018 September | September]]; [[2018 October | October]]; [[2018 November | November]]; [[2018 December | December]]

[[2019 January]]; [[2019 February | February]]; [[2019 March | March]]; [[2019 April | April]]; [[2019 May | May]]; [[2019 June | June]];
[[2019 July | July]]; [[2019 August | August]]; [[2019 September | September]]; [[2019 October | October]]; [[2019 November | November]]; [[2019 December | December]]

[[2020 January]]; [[2020 February | February]]; [[2020 March | March]]; [[2020 April | April]]; [[2020 May | May]]; [[2020 June | June]];
[[2020 July | July]]; [[2020 August | August]]; [[2020 September | September]]; [[2020 October | October]]; [[2020 November | November]]; [[2020 December | December]]

[[2021 January]]; [[2021 February | February]]; [[2021 March | March]]; [[2021 April | April]]; [[2021 May | May]]; [[2021 June | June]];
[[2021 July | July]]; [[2021 August | August]]; [[2021 September | September]]; [[2021 October | October]]; [[2021 November | November]]; [[2021 December | December]]

[[2022 SQL Outage]]

[[2023 January]]; [[2023 February | February]]; [[2023 March | March]]; [[2023 April | April]]; [[2023 May | May]]; [[2023 June | June]];
[[2023 July | July]]; [[2023 August | August]]; [[2023 September | September]]; [[2023 October | October]]; [[2023 November | November]]; [[2023 December | December]]

[[2024 January]]; [[2024 February | February]]; [[2024 March | March]];[[2024 April | April]];[[2024 May |May]]; [[2024 June | June]]; [[2024 July | July]]; [[2024 August | August]];
[[2024 September | September]]; [[2024 October | October]]; [[2024 November | November]]; [[2024 December | December]]

[[2025 January]]; [[2025 February | February]]; [[2025 March | March]];[[2025 April | April]];[[2025 May |May]]; [[2025 June | June]]; [[2025 July | July]]; [[2025 August | August]];
[[2025 September | September]]; [[2025 October | October]]; [[2025 November | November]]; [[2025 December | December]]

== EOVSA Scientist on Duty ==
* Scientist on Duty (SoD): EOVSA team members take turns and serve as an SoD to work with our onsite observatory staff on day-to-day observing. They are also responsible for monitoring solar activities and ensuring that the data we collect are of high quality.
* SoD observing logs:
** 2024: [https://docs.google.com/document/d/1QDWw5y4HpcE7CSpzXwftMqQT4FDgNJj-6fRrgWrqdug/edit?usp=sharing May (and before that)], [https://docs.google.com/document/d/1Rh2gYBV2E454xVYEv8jx5IXKd1N2Z05ns4dhI2XCE08/edit?usp=sharing June], [https://docs.google.com/document/d/1beUpp6rgwjqSxKbuHzXIR9hhPrGyi0j-SjtEIeav9Vg/edit?usp=sharing July], [https://docs.google.com/document/d/1pSzUXW5gd-4cZAR-gglTUVM_J2UHMa4wYJ2AzD4cdEo/edit?usp=sharing August], [https://docs.google.com/document/d/18pArAP0kRDhXHbty_y3TtrygmWkC2oLn-UD7njIpRIo/edit?usp=sharing September], [https://docs.google.com/document/d/1Qt6vhrqPAOG7W5Y_tLiod_QgNR1FDyzRxQcg6_oJQd4/edit?usp=sharing October], [https://docs.google.com/document/d/1pv9-Wne80FCrg0J5BkjOafmof_s3jlnc9HwyzWkIBfU/edit?usp=sharing November], [https://docs.google.com/document/d/1O5svOVwQZbUON1GMR_8nBR5LAL0M8RM2_zWW4oeBiLk/edit?usp=sharing December]
* SoD instructions:
** Daily routines: see [https://docs.google.com/document/d/1_iGnMRRrvb85Z0vT8-LzgQmCOKDSATEuQ0vTsn2C-dc/edit?usp=sharing SoD Routines] for detailed instructions.
** Instructions for [[making quick-look flare spectrograms and movies]]

==OVRO-LWA Solar-Dedicated Spectroscopic Imager==
The OVRO-LWA (Owens Valley Radio Observatory Long Wavelength Array) has recently been upgraded to include a solar-dedicated beam and two solar imaging modes (slow visibilities of 352 antennas with a 10-s cadence, and fast visibilities of 48 antennas with a 0.1-s cadence). The large collecting area and excellent calibration provide unprecedented high-sensitivity imaging of the quiet Sun and bursts. The array is currently in commissioning and observations are not yet continuous, but they are becoming more so. See the daily realtime data at http://ovsa.njit.edu/status.php for '''real-time display of the spectrogram and a selection of images''', both updated on a 1-min cadence.

===Solar-Dedicated Modes===
* Beamformer: the beamformer uses the 256 core antennas to form a synthesized beam of more than 1 degree in size that tracks the Sun from sunrise to sunset. This permits a continuous record of the full-Stokes total flux (without spatial resolution) of the Sun (a dynamic spectrum) with 24 kHz frequency resolution (3072 frequencies from 15-90 MHz) and as low as 1 ms time resolution.

* Slow Visibility Imaging: in this mode, the entire 352-element array is interferometrically correlated to provide visibilities for imaging at all 3072 frequencies at 10-s time resolution. This is ideal for imaging quiet Sun and slowly-varying emission such as coronal mass ejections and active region variability.

* Fast Visibility Imaging: in this mode, a subset of 48 antennas (chosen to include mainly outer antennas to maintain good spatial resolution) is interferometrically correlated to provide visibilities for imaging at 768 frequencies (96 kHz frequency resolution) at 0.1-s time resolution. This is ideal for imaging rapidly varying emission such as type II and type III bursts as well as many other solar spectral fine structures.

===Inital Data Access===
In its current commissioning state, we try to run the beamformer and imaging pipeline every day in real-time since November 2023 (no latency for beamforming spectrograms and 5-10 min latency for images). Quicklook real-time spectrograms/images can be accessed from http://ovsa.njit.edu/status.php. To access data from previous days, use the following links (replace yyyymmdd with the date you desire):
* Quicklook beamformer total-power spectrograms: http://ovsa.njit.edu/lwa-data/1min_spectra/yyyymmdd/. Check this link for additional daily plots [[Daily OVRO-LWA Beamformer Data]].
* Quicklook multi-frequency movies at 1-min cadence: http://ovsa.njit.edu/lwa-data/1min_images/yyyymmdd/movie_yyyy-mm-dd.html

Note our pipeline processing development is still in the early phase. For example, absolute flux calibrations have not been done for the beamformer spectrograms. Also, artificial effects (including ionospheric refraction effects) are present in the images that cause distortions/shifts. We caution interested users only to consider them for quick-look purposes at this point. Please contact the EOVSA PIs (Dale Gary, Bin Chen) if you intend to use them for science.

===OVRO-LWA Operation Notes===

[[OVRO-LWA Operation Notes]]

== Tohbans ==

[[Trouble Shooting Guide]]

[[Tohban Records]]

[[Owen's Notes]]

[[Caius' Notes]]

[[Tohban EOVSA Imaging Tutorial A-Z]]

[[Tohban OVRO-LWA Imaging Tutorial]]

[[Tohban Guide to Self Calibration and Imaging for EOVSA]]

[[Guide to Upgrade SolarSoft(SSW)]]

== EOVSA Publications ==
Here is a (partial) list of publications that utilize EOVSA data. See also the collection of EOVSA publications at [https://ui.adsabs.harvard.edu/public-libraries/eQ7HfPkySqydu-B8BCt6QQ this NASA/ADS Library].
; 2024
: Collier, H., Hayes, L. A., Yu, S., Battaglia, A. F., Ashfield, W., Polito, V., Harra, L. K., & Krucker, S. (2024), arXiv e-prints, arXiv:2402.10546. [https://ui.adsabs.harvard.edu/abs/2024arXiv240210546C “Localising pulsations in the hard X-ray and microwave emission of an X-class flare”]
: Saqri, J., Veronig, A. M., Battaglia, A. F., Dickson, E. C. M., Gary, D. E., & Krucker, S. (2024), Astronomy and Astrophysics, 683, A41. [https://ui.adsabs.harvard.edu/abs/2024A&A...683A..41S "Efficiency of solar microflares in accelerating electrons when rooted in a sunspot"]
; 2023
: Tan, B., Yan, Y., Huang, J., Zhang, Y., Tan, C., & Zhu, X. (2023), Advances in Space Research, 72, 5563. [https://ui.adsabs.harvard.edu/abs/2023AdSpR..72.5563T "The physics of solar spectral imaging observations in dm-cm wavelengths and the application on space weather"]

: Li, D., Li, Z., Shi, F., Su, Y., Chen, W., Yu, F., Li, C., Qiu, Y., Huang, Y., & Ning, Z. (2023), Astronomy and Astrophysics, 680, L15. [https://ui.adsabs.harvard.edu/abs/2023A&A...680L..15L "Observational signature of continuously operating drivers of decayless kink oscillation"]

: Wang, M., Chen, B., Yu, S., Gary, D. E., Lee, J., Wang, H., & Cohen, C. (2023), The Astrophysical Journal, 954, 32. [https://ui.adsabs.harvard.edu/abs/2023ApJ...954...32W "The Solar Origin of an In Situ Type III Radio Burst Event"]

: Gary, D. E. (2023), Annual Review of Astronomy and Astrophysics, 61, 427. [https://ui.adsabs.harvard.edu/abs/2023ARA&A..61..427G "New Insights from Imaging Spectroscopy of Solar Radio Emission"]

: Nita, G. M., Fleishman, G. D., Kuznetsov, A. A., Anfinogentov, S. A., Stupishin, A. G., Kontar, E. P., Schonfeld, S. J., Klimchuk, J. A., & Gary, D. E. (2023), The Astrophysical Journal Supplement Series, 267, 6. [https://ui.adsabs.harvard.edu/abs/2023ApJS..267....6N "Data-constrained Solar Modeling with GX Simulator"]

: Song, D.-C., Tian, J., Li, Y., Ding, M. D., Su, Y., Yu, S., Hong, J., Qiu, Y., Rao, S., Liu, X., Li, Q., Chen, X., Li, C., & Fang, C. (2023), The Astrophysical Journal, 952, L6. [https://ui.adsabs.harvard.edu/abs/2023ApJ...952L...6S "Spectral Observations and Modeling of a Solar White-light Flare Observed by CHASE"]

: Mondal, S., Chen, B., & Yu, S. (2023), The Astrophysical Journal, 949, 56. [https://ui.adsabs.harvard.edu/abs/2023ApJ...949...56M "Multifrequency Microwave Imaging of Weak Transients from the Quiet Solar Corona"]

: Kontar, E. P., Emslie, A. G., Motorina, G. G., & Dennis, B. R. (2023), The Astrophysical Journal, 947, L13. [https://ui.adsabs.harvard.edu/abs/2023ApJ...947L..13K "The Efficiency of Electron Acceleration during the Impulsive Phase of a Solar Flare"]

: Saqri, J., Veronig, A. M., Dickson, E. C. M., Podladchikova, T., Warmuth, A., Xiao, H., Gary, D. E., Battaglia, A. F., & Krucker, S. (2023), Astronomy and Astrophysics, 672, A23. [https://ui.adsabs.harvard.edu/abs/2023A&A...672A..23S "Multi-point study of the energy release and impulsive CME dynamics in an eruptive C7 flare"]
; 2022

: Kou, Y., Cheng, X., Wang, Y., Yu, S., Chen, B., Kontar, E. P., & Ding, M. (2022), Nature Communications, 13, 7680. [https://ui.adsabs.harvard.edu/abs/2022NatCo..13.7680K "Microwave imaging of quasi-periodic pulsations at flare current sheet"]

: Chertok, I. M. (2022), Monthly Notices of the Royal Astronomical Society, 517, 2709. [https://ui.adsabs.harvard.edu/abs/2022MNRAS.517.2709C "On some features of the solar proton event on 2021 October 28 - GLE73"]

: Lörinčík, J., Polito, V., De Pontieu, B., Yu, S., & Freij, N. (2022), Frontiers in Astronomy and Space Sciences, 9, 334. [https://ui.adsabs.harvard.edu/abs/2022FrASS...940945L "Rapid variations of Si IV spectra in a flare observed by interface region imaging spectrograph at a sub-second cadence"]

: Klein, K.-L., Musset, S., Vilmer, N., Briand, C., Krucker, S., Francesco Battaglia, A., Dresing, N., Palmroos, C., & Gary, D. E. (2022), Astronomy and Astrophysics, 663, A173. [https://ui.adsabs.harvard.edu/abs/2022A&A...663A.173K "The relativistic solar particle event on 28 October 2021: Evidence of particle acceleration within and escape from the solar corona"]

: Fleishman, G. D., Nita, G. M., Chen, B., Yu, S., & Gary, D. E. (2022), Nature, 606, 674. [https://ui.adsabs.harvard.edu/abs/2022Natur.606..674F "Solar flare accelerates nearly all electrons in a large coronal volume"]

: Li, X., Guo, F., Chen, B., Shen, C., & Glesener, L. (2022), The Astrophysical Journal, 932, 92. [https://ui.adsabs.harvard.edu/abs/2022ApJ...932...92L "Modeling Electron Acceleration and Transport in the Early Impulsive Phase of the 2017 September 10th Solar Flare"]

: Zhang, J., Chen, B., Yu, S., Tian, H., Wei, Y., Chen, H., Tan, G., Luo, Y., & Chen, X. (2022), The Astrophysical Journal, 932, 53. [https://ui.adsabs.harvard.edu/abs/2022ApJ...932...53Z "Implications for Additional Plasma Heating Driving the Extreme-ultraviolet Late Phase of a Solar Flare with Microwave Imaging Spectroscopy"]

: Liu, N., Jing, J., Xu, Y., & Wang, H. (2022), The Astrophysical Journal, 930, 154. [https://ui.adsabs.harvard.edu/abs/2022ApJ...930..154L "Multi-instrument Comparative Study of Temperature, Number Density, and Emission Measure during the Precursor Phase of a Solar Flare"]

: López, F. M., Giménez de Castro, C. G., Mandrini, C. H., Simões, P. J. A., Cristiani, G. D., Gary, D. E., Francile, C., & Démoulin, P. (2022), Astronomy and Astrophysics, 657, A51. [https://ui.adsabs.harvard.edu/abs/2022A&A...657A..51L "A solar flare driven by thermal conduction observed in mid-infrared"]

: Unverferth, J., & Longcope, D. (2021), The Astrophysical Journal, 923, 248. [https://ui.adsabs.harvard.edu/abs/2021ApJ...923..248U "Examining Flux Tube Interactions as a Cause of Sub-alfvénic Outflow"]
;2021

: Wei, Y., Chen, B., Yu, S., Wang, H., Jing, J., & Gary, D. E. (2021), The Astrophysical Journal, 923, 213. [https://ui.adsabs.harvard.edu/abs/2021ApJ...923..213W "Coronal Magnetic Field Measurements along a Partially Erupting Filament in a Solar Flare"]

: Jing, J., Inoue, S., Lee, J., Li, Q., Nita, G. M., Xu, Y., Liu, C., Gary, D. E., & Wang, H. (2021), The Astrophysical Journal, 922, 108. [https://ui.adsabs.harvard.edu/abs/2021ApJ...922..108J "Understanding the Initiation of the M2.4 Flare on 2017 July 14"]

: Battaglia, A. F., Saqri, J., Massa, P., Perracchione, E., Dickson, E. C. M., Xiao, H., Veronig, A. M., Warmuth, A., Battaglia, M., Hurford, G. J., Meuris, A., Limousin, O., Etesi, L., Maloney, S. A., Schwartz, R. A., Kuhar, M., Schuller, F., Senthamizh Pavai, V., Musset, S., Ryan, D. F., Kleint, L., Piana, M., Massone, A. M., Benvenuto, F., Sylwester, J., Litwicka, M., Stȩślicki, M., Mrozek, T., Vilmer, N., Fárník, F., Kašparová, J., Mann, G., Gallagher, P. T., Dennis, B. R., Csillaghy, A., Benz, A. O., & Krucker, S. (2021), Astronomy and Astrophysics, 656, A4. [https://ui.adsabs.harvard.edu/abs/2021A&A...656A...4B "STIX X-ray microflare observations during the Solar Orbiter commissioning phase"]

: Shaik, S. B., & Gary, D. E. (2021), The Astrophysical Journal, 919, 44. [https://ui.adsabs.harvard.edu/abs/2021ApJ...919...44S "Implications of Flat Optically Thick Microwave Spectra in Solar Flares for Source Size and Morphology"]

: Kocharov, L., Omodei, N., Mishev, A., Pesce-Rollins, M., Longo, F., Yu, S., Gary, D. E., Vainio, R., & Usoskin, I. (2021), The Astrophysical Journal, 915, 12. [https://ui.adsabs.harvard.edu/abs/2021ApJ...915...12K "Multiple Sources of Solar High-energy Protons"]

: Chen, B., Battaglia, M., Krucker, S., Reeves, K. K., & Glesener, L. (2021), The Astrophysical Journal, 908, L55. [https://ui.adsabs.harvard.edu/abs/2021ApJ...908L..55C "Energetic Electron Distribution of the Coronal Acceleration Region: First Results from Joint Microwave and Hard X-Ray Imaging Spectroscopy"]

: Chhabra, S., Gary, D. E., Hallinan, G., Anderson, M. M., Chen, B., Greenhill, L. J., & Price, D. C. (2021), The Astrophysical Journal, 906, 132. [https://ui.adsabs.harvard.edu/abs/2021ApJ...906..132C "Imaging Spectroscopy of CME-associated Solar Radio Bursts using OVRO-LWA"]
;2020 and earlier

: Reeves, K. K., Polito, V., Chen, B., Galan, G., Yu, S., Liu, W., & Li, G. (2020), The Astrophysical Journal, 905, 165. [https://ui.adsabs.harvard.edu/abs/2020ApJ...905..165R "Hot Plasma Flows and Oscillations in the Loop-top Region During the 2017 September 10 X8.2 Solar Flare"]

: Nindos, A. (2020), Frontiers in Astronomy and Space Sciences, 7, 57. [https://ui.adsabs.harvard.edu/abs/2020FrASS...7...57N "Incoherent Solar Radio Emission"]

: Yu, S., Chen, B., Reeves, K. K., Gary, D. E., Musset, S., Fleishman, G. D., Nita, G. M., & Glesener, L. (2020), The Astrophysical Journal, 900, 17. [https://ui.adsabs.harvard.edu/abs/2020ApJ...900...17Y "Magnetic Reconnection during the Post-impulsive Phase of a Long-duration Solar Flare: Bidirectional Outflows as a Cause of Microwave and X-Ray Bursts"]

: Chen, B., Yu, S., Reeves, K. K., & Gary, D. E. (2020), The Astrophysical Journal, 895, L50. [https://ui.adsabs.harvard.edu/abs/2020ApJ...895L..50C "Microwave Spectral Imaging of an Erupting Magnetic Flux Rope: Implications for the Standard Solar Flare Model in Three Dimensions"]

: Kuroda, N., Fleishman, G. D., Gary, D. E., Nita, G. M., Chen, B., & Yu, S. (2020), Frontiers in Astronomy and Space Sciences, 7, 22. [https://ui.adsabs.harvard.edu/abs/2020FrASS...7...22K "Evolution of Flare-accelerated Electrons Quantified by Spatially Resolved Analysis"]

: Glesener, L., Krucker, S., Duncan, J., Hannah, I. G., Grefenstette, B. W., Chen, B., Smith, D. M., White, S. M., & Hudson, H. (2020), The Astrophysical Journal, 891, L34. [https://ui.adsabs.harvard.edu/abs/2020ApJ...891L..34G "Accelerated Electrons Observed Down to <7 keV in a NuSTAR Solar Microflare"]

: Karlický, M., Chen, B., Gary, D. E., Kašparová, J., & Rybák, J. (2020), The Astrophysical Journal, 889, 72. [https://ui.adsabs.harvard.edu/abs/2020ApJ...889...72K "Drifting Pulsation Structure at the Very Beginning of the 2017 September 10 Limb Flare"]

: Fleishman, G. D., Gary, D. E., Chen, B., Kuroda, N., Yu, S., & Nita, G. M. (2020), Science, 367, 278. [https://ui.adsabs.harvard.edu/abs/2020Sci...367..278F "Decay of the coronal magnetic field can release sufficient energy to power a solar flare"]

: Chen, B., Shen, C., Gary, D. E., Reeves, K. K., Fleishman, G. D., Yu, S., Guo, F., Krucker, S., Lin, J., Nita, G. M., & Kong, X. (2020), Nature Astronomy, 4, 1140. [https://ui.adsabs.harvard.edu/abs/2020NatAs...4.1140C "Measurement of magnetic field and relativistic electrons along a solar flare current sheet"]

: Lee, J. (2018), Journal of Astronomy and Space Sciences, 35, 211. [https://ui.adsabs.harvard.edu/abs/2018JASS...35..211L "Analysis of Solar Microwave Burst Spectrum, I. Nonuniform Magnetic Field"]

: Gary, D. E., Bastian, T. S., Chen, B., Fleishman, G. D., & Glesener, L. (2018), Science with a Next Generation Very Large Array, 517, 99. [https://ui.adsabs.harvard.edu/abs/2018ASPC..517...99G "Radio Observations of Solar Flares"]

: Polito, V., Dudík, J., Kašparová, J., Dzifčáková, E., Reeves, K. K., Testa, P., & Chen, B. (2018), The Astrophysical Journal, 864, 63. [https://ui.adsabs.harvard.edu/abs/2018ApJ...864...63P "Broad Non-Gaussian Fe XXIV Line Profiles in the Impulsive Phase of the 2017 September 10 X8.3-class Flare Observed by Hinode/EIS"]

: Gary, D. E., Chen, B., Dennis, B. R., Fleishman, G. D., Hurford, G. J., Krucker, S., McTiernan, J. M., Nita, G. M., Shih, A. Y., White, S. M., & Yu, S. (2018), The Astrophysical Journal, 863, 83. [https://ui.adsabs.harvard.edu/abs/2018ApJ...863...83G "Microwave and Hard X-Ray Observations of the 2017 September 10 Solar Limb Flare"]

: Fleishman, G. D., Nita, G. M., Kuroda, N., Jia, S., Tong, K., Wen, R. R., & Zhizhuo, Z. (2018), The Astrophysical Journal, 859, 17. [https://ui.adsabs.harvard.edu/abs/2018ApJ...859...17F "Revealing the Evolution of Non-thermal Electrons in Solar Flares Using 3D Modeling"]

: Kuroda, N., Gary, D. E., Wang, H., Fleishman, G. D., Nita, G. M., & Jing, J. (2018), The Astrophysical Journal, 852, 32. [https://ui.adsabs.harvard.edu/abs/2018ApJ...852...32K "Three-dimensional Forward-fit Modeling of the Hard X-Ray and Microwave Emissions of the 2015 June 22 M6.5 Flare"]

: Wang, H., Liu, C., Ahn, K., Xu, Y., Jing, J., Deng, N., Huang, N., Liu, R., Kusano, K., Fleishman, G. D., Gary, D. E., & Cao, W. (2017), Nature Astronomy, 1, 0085. [https://ui.adsabs.harvard.edu/abs/2017NatAs...1E..85W "High-resolution observations of flare precursors in the low solar atmosphere"]

: Nita, G. M., Hickish, J., MacMahon, D., & Gary, D. E. (2016), Journal of Astronomical Instrumentation, 5, 1641009-7366. [https://ui.adsabs.harvard.edu/abs/2016JAI.....541009N "EOVSA Implementation of a Spectral Kurtosis Correlator for Transient Detection and Classification"]

: Nita, G. M., & Gary, D. E. (2016), Journal of Geophysical Research (Space Physics), 121, 7353. [https://ui.adsabs.harvard.edu/abs/2016JGRA..121.7353N "Measurement of duration and signal-to-noise ratio of astronomical transients using a Spectral Kurtosis spectrometer"]

: Wang, Z., Gary, D. E., Fleishman, G. D., & White, S. M. (2015), The Astrophysical Journal, 805, 93. [https://ui.adsabs.harvard.edu/abs/2015ApJ...805...93W "Coronal Magnetography of a Simulated Solar Active Region from Microwave Imaging Spectropolarimetry"]

: Gary, D. E., Fleishman, G. D., & Nita, G. M. (2013), Solar Physics, 288, 549. [https://ui.adsabs.harvard.edu/abs/2013SoPh..288..549G "Magnetography of Solar Flaring Loops with Microwave Imaging Spectropolarimetry"]

== VLA Flare List and Publications ==
See [http://www.ovsa.njit.edu/wiki/index.php/VLA_Data_Survey#List_of_Jansky_VLA_Solar_Observations this link] for a list of flare observations made by the [https://science.nrao.edu/facilities/vla/ Karl G. Jansky Very Large Array] (VLA). Below is a partial list of publications that utilize VLA solar data (see also [https://ui.adsabs.harvard.edu/public-libraries/ZwbjpLo9RS-viufWEoQ95Q this NASA/ADS Library]).
* [https://ui.adsabs.harvard.edu/abs/2022ApJ...940..137L/abstract Luo et al. (2022), ApJ, 940, 137] ''Multiple Regions of Nonthermal Quasiperiodic Pulsations during the Impulsive Phase of a Solar Flare''
* [https://ui.adsabs.harvard.edu/abs/2021ApJ...922..134B/abstract Battaglia et al. (2021), ApJ, 922, 134] ''Multiple Electron Acceleration Instances during a Series of Solar Microflares Observed Simultaneously at X-Rays and Microwaves''
* [https://ui.adsabs.harvard.edu/abs/2021ApJ...911....4L/abstract Luo et al. (2021), ApJ, 911, 4] ''Radio Spectral Imaging of an M8.4 Eruptive Solar Flare: Possible Evidence of a Termination Shock''
* [https://ui.adsabs.harvard.edu/abs/2021ApJ...910...40Z/abstract Zhang et al. (2021), ApJ, 910, 40] ''Multiwavelength Observations of the Formation and Eruption of a Complex Filament''
* [https://ui.adsabs.harvard.edu/abs/2020ApJ...904...94S/abstract Sharma et al. (2020), ApJ, 904, 94] ''Radio and X-Ray Observations of Short-lived Episodes of Electron Acceleration in a Solar Microflare''
* [https://ui.adsabs.harvard.edu/abs/2019ApJ...884...63C/abstract Chen et al. (2019), ApJ, 884, 63] ''Radio Spectroscopic Imaging of a Solar Flare Termination Shock: Split-band Feature as Evidence for Shock Compression''
* [https://ui.adsabs.harvard.edu/abs/2019ApJ...872...71Y/abstract Yu & Chen (2019), ApJ, 872, 71] ''Possible Detection of Subsecond-period Propagating Magnetohydrodynamics Waves in Post-reconnection Magnetic Loops during a Two-ribbon Solar Flare''
* [https://ui.adsabs.harvard.edu/abs/2018ApJ...866...62C/abstract Chen et al. (2018), ApJ, 866, 62] ''Magnetic Reconnection Null Points as the Origin of Semirelativistic Electron Beams in a Solar Jet
''
* [https://ui.adsabs.harvard.edu/abs/2017ApJ...848...77W/abstract Wang et al. (2016), ApJ, 848, 77] ''Dynamic Spectral Imaging of Decimetric Fiber Bursts in an Eruptive Solar Flare''
* [https://ui.adsabs.harvard.edu/abs/2015Sci...350.1238C/abstract Chen et al. (2015), Science, 350, 1238] ''Particle acceleration by a solar flare termination shock''
* [https://ui.adsabs.harvard.edu/abs/2014ApJ...794..149C/abstract Chen et al. (2014), ApJ, 794, 149] ''Direct Evidence of an Eruptive, Filament-hosting Magnetic Flux Rope Leading to a Fast Solar Coronal Mass Ejection''
* [https://ui.adsabs.harvard.edu/abs/2013ApJ...763L..21C/abstract Chen et al. (2013), ApJL, 763, 21] ''Tracing Electron Beams in the Sun's Corona with Radio Dynamic Imaging Spectroscopy''

==Radio Data from Around The Heliosphere==
* [http://ovsa.njit.edu//wiki/index.php/Radio_Data_from_Around_the_World#Radio_Data_Access '' Radio Data '']

Delay Calibration

2024-10-16T16:57:54Z

Dgary: /* Practical Delay Setting */

= Delay Center Calibration =

== Practical Delay Setting ==
Whenever the ROACH boards (correlator) are rebooted, new delays have to be determined. Here is a practical guide to doing that. The broad steps are:
* Point the antennas at the geosynchronous satellite ECHO (with suitable attenuation to keep the receivers from overloading)
* Capture 1 second of data for analysis
* Analyze the data to find rough delay values
* If there are large delays, run delay_widget.py to adjust the delays in a "blind" mode
* Take at least 20 min of data on a calibrator
* Run delay_widget.py to fine tune the delays
* As soon as possible, run the X-Y delay calibration procedure on source 2253+161
Below are details of each step.

=== Point the antennas at geosynchronous satellite ECHO ===
This is easily accomplished using the schedule file '''geosat_echo_kband.scd'''. Load this file into the schedule (it tracks a single source for 24 h) and hit the Today button to update the date, then hit GO. This will track the satellite with all antennas, enter the appropriate attenuations, and start the kband.fsq sequence. NB: The data system will not start recording the data--instead we capture the data in the next step.

=== Capture 1 second of data ===
After all antennas are tracking (Ant 12 for some reason does not like to track exactly on a geosat, so you may have to ignore small errors there), then send the command '''$capture-1s geo''' from the Raw Command of the schedule. After about 10-15 s, the capture file should appear in the DPP on /disk1/PRT/PRT<yyyymmddhhmmss>geo.dat.

=== Analyze the data to find rough delay values ===

[[File:sat_delays.png|thumb|400px| '''Figure 1:''' Plot of the phase relative to Ant 14 for data taken on the satellite CIEL-2 on 2022-02-12. Each panel shows the phase in radians vs. fine frequency channel (red), a linear phase slope fit (blue), and the difference between data and fit (green). In this case there is a huge delay for antenna 14 and antenna 10 was not tracking.]]

On the Pipeline computer get into ipython and issue the following commands:
import pcapture2 as p
out = p.rd_jspec('/dppdata1/PRT/PRT<yyyymmddhhmmss>geo.dat')
p.prt_dla(out, ref=None, refant=14, doplot=True)
This will print a table of delays relative to antenna 14 to the screen as below (asterisks mark values with high standard deviation) and also plot the result as in Figure 1:
Ant: 1 Steps: 184.2 stdev [deg]: 6.7 Delay [ns]: 230.310
*Ant: 2 Steps: 183.0 stdev [deg]: 12.0 Delay [ns]: 228.688
*Ant: 3 Steps: 185.0 stdev [deg]: 101.0 Delay [ns]: 231.247
*Ant: 4 Steps: 188.8 stdev [deg]: 15.3 Delay [ns]: 236.018
*Ant: 5 Steps: 189.4 stdev [deg]: 13.7 Delay [ns]: 236.759
Ant: 6 Steps: 189.8 stdev [deg]: 9.2 Delay [ns]: 237.302
*Ant: 7 Steps: 189.7 stdev [deg]: 19.3 Delay [ns]: 237.145
Ant: 8 Steps: 194.1 stdev [deg]: 7.7 Delay [ns]: 242.625
*Ant: 9 Steps: 188.7 stdev [deg]: 11.6 Delay [ns]: 235.863
*Ant: 10 Steps: -20.9 stdev [deg]: 104.9 Delay [ns]: -26.142
*Ant: 11 Steps: 197.5 stdev [deg]: 13.4 Delay [ns]: 246.862
Ant: 12 Steps: 191.4 stdev [deg]: 8.6 Delay [ns]: 239.295
Ant: 13 Steps: 195.7 stdev [deg]: 5.4 Delay [ns]: 244.629
Ant: 14 Steps: 0.0 stdev [deg]: 0.0 Delay [ns]: 0.000

The delays that would be tried in delay_widget.py are those in the last column. Note that in this case the Ant 14 delay was way off, so it shows up as huge delays in all antennas because these are delays with respect to the erroneous Ant 14. Note also that the delays get quite far off for the higher-numbered antennas--not sure why.

== Background ==
[[File:del_centr_f1.png|thumb|800px| Figure 1: EOVSA data in the 12.15-12.55 GHz band on CIEL-2, taken with nearly optimal delay (in this case -7 steps in Y relative to X channel) on Antenna 4 in R (blue) and L (green) polarizations. The channels and their polarizations agree well with the nominal band centers, shown with the blue and green vertical lines. Each channel is relatively flat, and separated by narrow notches, but the R and L bands overlap in an interleaving fashion. The band amplitudes vary because the transmissions are in “spot beams” pointed at different places in North America, not all pointing directly at central California.]]

The signals from each antenna have to reach the correlator with the appropriate delays to compensate for cable length differences. For most interferometers, only relative delays between antennas matters, but because the EOVSA converts X and Y polarization into R and L, it appears that the relative delay requirement between X and Y for a given antenna is even more stringent (see section 2). The problem is especially tricky for EOVSA, because the ROACH boards use the KatADC digitizers, which have a clock speed that is a factor of 4 higher than the FPGA clock, so that four-way multiplexing is done. The initialization of this multiplexing is random on startup of the ROACH boards, so there can be differences of up to 4 coarse delay steps, which has to be calibrated every time the ROACHes are restarted. Thus, we need a delay center calibration procedure that can be done quickly and reliably.

This document describes the use of geostationary satellites for delay center calibration, as well as some lessons learned by using this method. This concerns both interferometric phase on each baseline and polarization purity on each antenna, but both can be accomplished at the same time by choosing a satellite with both R and L polarized channels.

The precise analysis needed depends strongly on the choice of geostationary satellite. The experiments done so far have used the CIEL-2 satellite, which has alternating R- and L-polarized channels that overlap. The transmission bands of CIEL-2 are well demonstrated by the actual EOVSA total power data shown in '''Figure 1'''.

The CIEL-2 satellite is located at <math>149^o</math> W longitude, and so is fairly isolated from other satellites, which become close together at more eastern longitudes. It is good to avoid having more than one satellite in the 2.1-m antenna beam at a time. The EOVSA beam is relatively small at this <math>K_u</math> band frequency, which also helps.

[[File:del_centr_f2.png|thumb|800px| Figure 2: R-channel amplitudes taken on CIEL-2 while stepping Y-channel delays relative to X by one step/s. The alternation between R and L on every step is seen at high channel numbers, while it takes two steps to swtich at channel 2048, and four steps at channel 1024. The optimum step is around 0.5.]]

To observe a geostationary satellite with the EOVSA system is quite easy. The system automatically downloads the latest coordinate (two-line element, or TLE) files from http://www.celestrak.com/, finds the satellite name in the file, and converts the TLE coordinates to the required RA and Dec table needed to track the satellite. The satellite name for CIEL-2 is just CIEL-2, but because the names have to match exactly, it is sometimes necessary to manually download the file http://www.celestrak.com/NORAD/elements/geo.txt and find the exact spelling of the satellite name. If there are spaces in the name (e.g. “GALAXY 3C (G-3C)”), replace them with underscores (“GALAXY_3C_(G-3C)”). Because these are geostationary satellites, when the track tables are loaded into the antennas the RA should advance 1 s for each second, in order to keep the actual position fixed. However, the satellites do execute small ellipses on the sky, so RA and Dec do change very slightly.

=== Delay Centers and R/L Polarization ===
Because the R and L polarization is obtained from X and Y in the digital correlator, the delays between X and Y channels must be kept very close to zero. In fact, for Nyquist sampling of the IF that we use, a single coarse delay step at the high end corresponds to a complete swap of polarization R -> L and L -> R. This is nicely demonstrated by '''Figure 2''', which shows data taken on the Ciel-2 geostationary satellite in R polarization. As shown in '''Figure 1''', the broadcast frequencies on this satellite alternate between R and L polarization. As the delay is swept from -10 steps to +5 steps, the polarization pattern, which nominally should look like the one at delay step +1, instead alternates between R and L polarization on each step at frequency channel 4096, but takes two steps at channel 2048, and four steps at channel 1024, etc. The alternation at lower channels produces a symmetric pattern suggested by the two white curves overlaid on the plot, and helps to show that the best step will be somewhere between steps 1 and 0, but closer to step 1. Unfortunately, to get the correct delay within less than a coarse delay step requires either the insertion of a small length of cable equivalent to the desired partial-step delay, or else an adjustment of the complex number used in the correlator to convert X and Y to R and L.

[[File:del_centr_f3.png|thumb|800px| '''Figure 3:''' Plots of the data in Figure 2 at close to the optimal delay and at the adjacent delay offsets above and below it. Note that the color of the channels near 12.5 GHz (180-degrees per step) alternate while those near 12.2 GHz do not. At 12.35 GHz, the top plot is X,Y, middle plot is R,L, and bottom plot is Y,X, etc., as the phase drift caused by the delay is 90-degrees per step.]]

In the case of '''Figure 2''', the optimum delay of Y with respect to X is about +0.5 steps, which can be accomplished by adding an approximately 6-inch cable in the Y-channel, calculated from (0.5 step)*(1.25 ns/step)*(0.85 ft/ns), where the latter factor takes into account the slower propagation of light in cable. Note that only fractional steps need to be adjusted by adding short cables, since whole steps can be adjusted simply by adjusting the coarse delay offsets in the file delay_centers.txt. For example, the data shown in Figure 3 are the same as in '''Figure 2''', but taken at a time when the optimal delay was 7 steps off.

Instead of adding short cables, it is likely that merely adjusting the complex factor used to convert X, Y to R, L in the correlator can be adjusted for the appropriate delay (i.e. instead of a constant, an appropriate slope in phase correction can be introduced), but I think it is best for now to try to get an optimized analog system so that any such phase corrections are either not needed or kept small.

Whenever the ROACH boards are power-cycled or restarted, we can expect the phase of the 4-way multiplexing of the digitized signal to change randomly between 0, 1, 2, and 3 in units of coarse steps. Because the two polarizations of each antenna go through the same digitizer, it may be that the two channels of a given digitizer change their multiplexing phase together, in which case the relative X and Y delay will not change. This remains to be confirmed. If so, an analysis like the above is only needed on an occasional basis in case some analog component or cable changes. If the X and Y multiplexing phases do change independently, then the above analysis will have to be done on each restart.

=== Delay Centers and Cross-Correlation ===
The above considerations affect the relative X vs. Y delays on a given antenna. In addition, the overall delays of X on each antenna relative to X on the others, and likewise for Y, have to be maintained at the optimum value by examining the slope in phase across the band while on a satellite. Note that the cross-correlation measurements are completely independent in X and Y, so optimal delays from cross-correlation do not guarantee optimal delays for the purpose of polarization as described above. In fact, it is probably best to do cross-correlation optimization using the correlator in X and Y mode rather than R and L, to avoid conflating the two.

== Fine Delay Calibration ==

=== 1. Background ===
This document describes the principles to be considered for fine delay correction of EOVSA correlated data. It will be helpful to refer to the memo Documentation of Downconversion and Tuning, which describes the three consecutive frequency-conversion operations required to tune and isolate a clean 500 MHz IF band from the 1-18 GHz RF band. We will refer to several frequencies in this document, defined below:

<math>\omega_{RF} =</math> angular frequency of the RF, which nominally ranges over <math>2\pi\times({\rm 1-18 GHz})</math>

<math>\omega_{VLO} =</math> angular frequency of the variable (tuning) LO, which ranges over <math>2\pi\times({\rm 21.5-38 GHz})</math>

<math>\omega_{FLO} =</math> angular frequency of the fixed LO, which is <math>2\pi\times({\rm 21.15 GHz})</math>

<math>\omega_{ADC} =</math> angular frequency of the ADC clock, which is now <math>2\pi\times({\rm 0.8 GHz})</math> -> will be <math>2\pi\times({\rm 1.2 GHz})</math>

Note that for EOVSA’s nominal operation, <math>\omega_{VLO}</math> has only discrete values corresponding to frequencies <math>f_{VLO} = 21.5, 22, 22.5, \dots, 38</math> GHz, while <math>\omega_{RF}</math> varies continuously. The tuning of <math>\omega_{VLO}</math> to these discrete values provides the 500-MHz-wide bands labeled as integers (1-34) in the scan header as FSeqList. The relationship between the band numbers in FSeqList and <math>f_{VLO}</math> in GHz is
<center><math>f_{LO} = {\rm FSeqList}/2 + 21 {\rm[GHz]}</math>. (1)</center>

This discussion will follow the discussion in Appendix A of Liu et al. (2007), see Figure 1 below.
[[File:5.png|right|thumb|600px|Figure 1: Diagram showing the three downconversions.]]

As shown in Figure 1, a plane wave arrives later for the antenna on the left, so its fluctuating waveform is shifted by a phase , where is the continuously varying geometric delay required to track the source. The first downconversion by the variable LO inverts the frequencies on both antennas and shifts them by the oscillator frequency . The second downconversion by the fixed LO inverts and shifts the frequencies by in a similar manner. This produces an IF frequency in the range 600-1200 MHz. The final downconversion is done by the ADC, which does a final inversion of the frequencies and shifts them by . After digitization, an integer “course delay” rounded to the nearest digitizer clock step, is inserted into the right-hand antenna. After correlation (multiplication and averaging), the fast fluctuation involving t is eliminated, but the signal is left with a fluctuating phase
(2)
where is the non-integer “fine delay,” which must be applied on a channel-by-channel basis across the 600 MHz IF band, while the first term is constant over the band (for a given tuning frequency). The phase in equation (2) is to be subtracted from the phase of the baseline.

=== 2, Cross-Checks ===
To verify that the above is correct, first note that the frequency
(3)
is the IF frequency corresponding to RF frequency . As shown in the memo Documentation of Downconversion and Tuning, (see Figure 2, reproduced from that document) for an ADC clock frequency of 1200 MHz, we expect (blue numbers in Figure 2) an RF frequency of, say, 2.5 GHz, to be at IF frequency 50 MHz when tuned to the 2-2.5 GHz band (FSeqList = 3), while the other end of the band, 2.0 GHz, should be at 550 MHz (i.e. the IF band is inverted relative to the RF).

[[File:6.png|600px|right|thumb|Figure 2: Schematic representation of the third EOVSA downconversion by the digitizer. The filtered second IF band on the left, whose frequency scale is marked in black (in MHz), is mirrored and converted to the IF band on the right, marked in blue (in MHz). The 600 MHz-wide digitized bandpass is shown in green, while the narrower 500 MHz target bandpass is shown by the inner dashed lines on the right.]]

Using equation (1), the variable LO would be tuned to 22.5 GHz for this band, so:
,
.
The equation (3) works for any band, when and are changed appropriately.
Likewise, if the ADC clock frequency is 800 MHz, as it is at present, then the lower part of the band (0-200 MHz) is overlapped, and the upper part of the band (200-400 MHz) is direct relative to the RF (see Figure 3, reproduced from the earlier memo).

[[File:7.png|thumb|400px|left|Figure 3: Schematic representation of the third EOVSA downconversion by the digitizer, when the digitizer clock is at the non-ideal frequency of 800 MHz. The second IF band is shown in black (in MHz), while the mirrored IF band partially overlaps and extends to the left, marked in blue. The green block indicates the downconverted, digitized bandpass, whose scale is shown in blue (in MHz). The part of the band contaminated with overlapping is shown as the darker green hatched area.]]

In this case, for the same 2.0-2.5 GHz band 3 as the earlier example, we expect 2.0 GHz RF to be at 150 MHz IF, 2.15 GHz to be at 0 MHz IF, 2.3 GHz to be again at 150 MHz, and 2.5 GHz RF to be at 350 MHz. For these four cases, equation (2) gives:
,
, , .
Note that any RF frequency above 2.15 GHz results in a negative IF frequency, which, when aliased about zero, becomes the absolute value of the IF frequency.
We conclude that equation (3) is accurate for any ADC clock and RF frequency.
Looking now at equation (2), the first term is the phase variation associated with natural fringes, while the second term is the channel-dependent phase associated with the “fine delay” (the difference between integer-stepped “coarse delay” and the true geometric delay). Let us look at these terms and verify that they have the expected behavior. Let’s rewrite this as:
.
The first term, , is constant for a given band, and by definition constant over a 1-s period since delay steps can only happen on 1-s boundaries. In fact, this term can remain constant for several minutes for short baselines that are not changing projected length very fast. The term can grow very large, and has stepwise discontinuities since varies in “coarse delay” steps. Because ranges from 21.5-38 GHz, for the case of an 800 MHz ADC clock the frequency term ranges from 7.226 radians/ns to 110.898 radians/ns (414-6354 degrees/ns). Since the steps in occur in 1.25 ns steps for an 800 MHz ADC clock, this is 517.5-7942.5 degrees/step. Although this seems large, it agrees with my analysis detailed in section 2.1 Delay Tracking, in the memo EOVSA_Calibration. There I found a maximum fringe rate of 6.6 Hz. Taking 6354 degrees/ns, and maximum delay rate of 0.364 ns/s from that memo, I have (6354 degrees/ns) (0.364 ns/s) / (360 degrees) = 6.44 Hz. The slight discrepancy is due to the above numbers referring to a frequency of 17.650 GHz (see next paragraph), whereas the memo used 18 GHz. Applying the correction, I get a fringe rate of 6.58 Hz.
The second term, , can also be quite large. Since in general can range from 1/2 step (0.625 ns) to +1/2 step (0.625 ns), for an RF frequency of 18 GHz, ranges from -4050 to 4050 degrees. It is puzzling that the total range, 8100 degrees, is not quite the same as the max degrees/step of the natural fringe term (7942.5 degrees). Ah, but the frequency 17.650 GHz does yield an exact match, which corresponds to 0 MHz in the band-34 IF, according to equation (3).

Delay Calibration

2024-10-16T16:57:16Z

Dgary: /* Delay Center Calibration */

= Delay Center Calibration =

== Practical Delay Setting ==
Whenever the ROACH boards (correlator) are rebooted, new delays have to be determined. Here is a practical guide to doing that. The broad steps are:
* Point the antennas at the geosynchronous satellite CIEL-2 (with suitable attenuation to keep the receivers from overloading)
* Capture 1 second of data for analysis
* Analyze the data to find rough delay values
* If there are large delays, run delay_widget.py to adjust the delays in a "blind" mode
* Take at least 20 min of data on a calibrator
* Run delay_widget.py to fine tune the delays
* As soon as possible, run the X-Y delay calibration procedure on source 2253+161
Below are details of each step.

=== Point the antennas at geosynchronous satellite ECHO ===
This is easily accomplished using the schedule file '''geosat_echo_kband.scd'''. Load this file into the schedule (it tracks a single source for 24 h) and hit the Today button to update the date, then hit GO. This will track the satellite with all antennas, enter the appropriate attenuations, and start the kband.fsq sequence. NB: The data system will not start recording the data--instead we capture the data in the next step.

=== Capture 1 second of data ===
After all antennas are tracking (Ant 12 for some reason does not like to track exactly on a geosat, so you may have to ignore small errors there), then send the command '''$capture-1s geo''' from the Raw Command of the schedule. After about 10-15 s, the capture file should appear in the DPP on /disk1/PRT/PRT<yyyymmddhhmmss>geo.dat.

=== Analyze the data to find rough delay values ===

[[File:sat_delays.png|thumb|400px| '''Figure 1:''' Plot of the phase relative to Ant 14 for data taken on the satellite CIEL-2 on 2022-02-12. Each panel shows the phase in radians vs. fine frequency channel (red), a linear phase slope fit (blue), and the difference between data and fit (green). In this case there is a huge delay for antenna 14 and antenna 10 was not tracking.]]

On the Pipeline computer get into ipython and issue the following commands:
import pcapture2 as p
out = p.rd_jspec('/dppdata1/PRT/PRT<yyyymmddhhmmss>geo.dat')
p.prt_dla(out, ref=None, refant=14, doplot=True)
This will print a table of delays relative to antenna 14 to the screen as below (asterisks mark values with high standard deviation) and also plot the result as in Figure 1:
Ant: 1 Steps: 184.2 stdev [deg]: 6.7 Delay [ns]: 230.310
*Ant: 2 Steps: 183.0 stdev [deg]: 12.0 Delay [ns]: 228.688
*Ant: 3 Steps: 185.0 stdev [deg]: 101.0 Delay [ns]: 231.247
*Ant: 4 Steps: 188.8 stdev [deg]: 15.3 Delay [ns]: 236.018
*Ant: 5 Steps: 189.4 stdev [deg]: 13.7 Delay [ns]: 236.759
Ant: 6 Steps: 189.8 stdev [deg]: 9.2 Delay [ns]: 237.302
*Ant: 7 Steps: 189.7 stdev [deg]: 19.3 Delay [ns]: 237.145
Ant: 8 Steps: 194.1 stdev [deg]: 7.7 Delay [ns]: 242.625
*Ant: 9 Steps: 188.7 stdev [deg]: 11.6 Delay [ns]: 235.863
*Ant: 10 Steps: -20.9 stdev [deg]: 104.9 Delay [ns]: -26.142
*Ant: 11 Steps: 197.5 stdev [deg]: 13.4 Delay [ns]: 246.862
Ant: 12 Steps: 191.4 stdev [deg]: 8.6 Delay [ns]: 239.295
Ant: 13 Steps: 195.7 stdev [deg]: 5.4 Delay [ns]: 244.629
Ant: 14 Steps: 0.0 stdev [deg]: 0.0 Delay [ns]: 0.000

The delays that would be tried in delay_widget.py are those in the last column. Note that in this case the Ant 14 delay was way off, so it shows up as huge delays in all antennas because these are delays with respect to the erroneous Ant 14. Note also that the delays get quite far off for the higher-numbered antennas--not sure why.

== Background ==
[[File:del_centr_f1.png|thumb|800px| Figure 1: EOVSA data in the 12.15-12.55 GHz band on CIEL-2, taken with nearly optimal delay (in this case -7 steps in Y relative to X channel) on Antenna 4 in R (blue) and L (green) polarizations. The channels and their polarizations agree well with the nominal band centers, shown with the blue and green vertical lines. Each channel is relatively flat, and separated by narrow notches, but the R and L bands overlap in an interleaving fashion. The band amplitudes vary because the transmissions are in “spot beams” pointed at different places in North America, not all pointing directly at central California.]]

The signals from each antenna have to reach the correlator with the appropriate delays to compensate for cable length differences. For most interferometers, only relative delays between antennas matters, but because the EOVSA converts X and Y polarization into R and L, it appears that the relative delay requirement between X and Y for a given antenna is even more stringent (see section 2). The problem is especially tricky for EOVSA, because the ROACH boards use the KatADC digitizers, which have a clock speed that is a factor of 4 higher than the FPGA clock, so that four-way multiplexing is done. The initialization of this multiplexing is random on startup of the ROACH boards, so there can be differences of up to 4 coarse delay steps, which has to be calibrated every time the ROACHes are restarted. Thus, we need a delay center calibration procedure that can be done quickly and reliably.

This document describes the use of geostationary satellites for delay center calibration, as well as some lessons learned by using this method. This concerns both interferometric phase on each baseline and polarization purity on each antenna, but both can be accomplished at the same time by choosing a satellite with both R and L polarized channels.

The precise analysis needed depends strongly on the choice of geostationary satellite. The experiments done so far have used the CIEL-2 satellite, which has alternating R- and L-polarized channels that overlap. The transmission bands of CIEL-2 are well demonstrated by the actual EOVSA total power data shown in '''Figure 1'''.

The CIEL-2 satellite is located at <math>149^o</math> W longitude, and so is fairly isolated from other satellites, which become close together at more eastern longitudes. It is good to avoid having more than one satellite in the 2.1-m antenna beam at a time. The EOVSA beam is relatively small at this <math>K_u</math> band frequency, which also helps.

[[File:del_centr_f2.png|thumb|800px| Figure 2: R-channel amplitudes taken on CIEL-2 while stepping Y-channel delays relative to X by one step/s. The alternation between R and L on every step is seen at high channel numbers, while it takes two steps to swtich at channel 2048, and four steps at channel 1024. The optimum step is around 0.5.]]

To observe a geostationary satellite with the EOVSA system is quite easy. The system automatically downloads the latest coordinate (two-line element, or TLE) files from http://www.celestrak.com/, finds the satellite name in the file, and converts the TLE coordinates to the required RA and Dec table needed to track the satellite. The satellite name for CIEL-2 is just CIEL-2, but because the names have to match exactly, it is sometimes necessary to manually download the file http://www.celestrak.com/NORAD/elements/geo.txt and find the exact spelling of the satellite name. If there are spaces in the name (e.g. “GALAXY 3C (G-3C)”), replace them with underscores (“GALAXY_3C_(G-3C)”). Because these are geostationary satellites, when the track tables are loaded into the antennas the RA should advance 1 s for each second, in order to keep the actual position fixed. However, the satellites do execute small ellipses on the sky, so RA and Dec do change very slightly.

=== Delay Centers and R/L Polarization ===
Because the R and L polarization is obtained from X and Y in the digital correlator, the delays between X and Y channels must be kept very close to zero. In fact, for Nyquist sampling of the IF that we use, a single coarse delay step at the high end corresponds to a complete swap of polarization R -> L and L -> R. This is nicely demonstrated by '''Figure 2''', which shows data taken on the Ciel-2 geostationary satellite in R polarization. As shown in '''Figure 1''', the broadcast frequencies on this satellite alternate between R and L polarization. As the delay is swept from -10 steps to +5 steps, the polarization pattern, which nominally should look like the one at delay step +1, instead alternates between R and L polarization on each step at frequency channel 4096, but takes two steps at channel 2048, and four steps at channel 1024, etc. The alternation at lower channels produces a symmetric pattern suggested by the two white curves overlaid on the plot, and helps to show that the best step will be somewhere between steps 1 and 0, but closer to step 1. Unfortunately, to get the correct delay within less than a coarse delay step requires either the insertion of a small length of cable equivalent to the desired partial-step delay, or else an adjustment of the complex number used in the correlator to convert X and Y to R and L.

[[File:del_centr_f3.png|thumb|800px| '''Figure 3:''' Plots of the data in Figure 2 at close to the optimal delay and at the adjacent delay offsets above and below it. Note that the color of the channels near 12.5 GHz (180-degrees per step) alternate while those near 12.2 GHz do not. At 12.35 GHz, the top plot is X,Y, middle plot is R,L, and bottom plot is Y,X, etc., as the phase drift caused by the delay is 90-degrees per step.]]

In the case of '''Figure 2''', the optimum delay of Y with respect to X is about +0.5 steps, which can be accomplished by adding an approximately 6-inch cable in the Y-channel, calculated from (0.5 step)*(1.25 ns/step)*(0.85 ft/ns), where the latter factor takes into account the slower propagation of light in cable. Note that only fractional steps need to be adjusted by adding short cables, since whole steps can be adjusted simply by adjusting the coarse delay offsets in the file delay_centers.txt. For example, the data shown in Figure 3 are the same as in '''Figure 2''', but taken at a time when the optimal delay was 7 steps off.

Instead of adding short cables, it is likely that merely adjusting the complex factor used to convert X, Y to R, L in the correlator can be adjusted for the appropriate delay (i.e. instead of a constant, an appropriate slope in phase correction can be introduced), but I think it is best for now to try to get an optimized analog system so that any such phase corrections are either not needed or kept small.

Whenever the ROACH boards are power-cycled or restarted, we can expect the phase of the 4-way multiplexing of the digitized signal to change randomly between 0, 1, 2, and 3 in units of coarse steps. Because the two polarizations of each antenna go through the same digitizer, it may be that the two channels of a given digitizer change their multiplexing phase together, in which case the relative X and Y delay will not change. This remains to be confirmed. If so, an analysis like the above is only needed on an occasional basis in case some analog component or cable changes. If the X and Y multiplexing phases do change independently, then the above analysis will have to be done on each restart.

=== Delay Centers and Cross-Correlation ===
The above considerations affect the relative X vs. Y delays on a given antenna. In addition, the overall delays of X on each antenna relative to X on the others, and likewise for Y, have to be maintained at the optimum value by examining the slope in phase across the band while on a satellite. Note that the cross-correlation measurements are completely independent in X and Y, so optimal delays from cross-correlation do not guarantee optimal delays for the purpose of polarization as described above. In fact, it is probably best to do cross-correlation optimization using the correlator in X and Y mode rather than R and L, to avoid conflating the two.

== Fine Delay Calibration ==

=== 1. Background ===
This document describes the principles to be considered for fine delay correction of EOVSA correlated data. It will be helpful to refer to the memo Documentation of Downconversion and Tuning, which describes the three consecutive frequency-conversion operations required to tune and isolate a clean 500 MHz IF band from the 1-18 GHz RF band. We will refer to several frequencies in this document, defined below:

<math>\omega_{RF} =</math> angular frequency of the RF, which nominally ranges over <math>2\pi\times({\rm 1-18 GHz})</math>

<math>\omega_{VLO} =</math> angular frequency of the variable (tuning) LO, which ranges over <math>2\pi\times({\rm 21.5-38 GHz})</math>

<math>\omega_{FLO} =</math> angular frequency of the fixed LO, which is <math>2\pi\times({\rm 21.15 GHz})</math>

<math>\omega_{ADC} =</math> angular frequency of the ADC clock, which is now <math>2\pi\times({\rm 0.8 GHz})</math> -> will be <math>2\pi\times({\rm 1.2 GHz})</math>

Note that for EOVSA’s nominal operation, <math>\omega_{VLO}</math> has only discrete values corresponding to frequencies <math>f_{VLO} = 21.5, 22, 22.5, \dots, 38</math> GHz, while <math>\omega_{RF}</math> varies continuously. The tuning of <math>\omega_{VLO}</math> to these discrete values provides the 500-MHz-wide bands labeled as integers (1-34) in the scan header as FSeqList. The relationship between the band numbers in FSeqList and <math>f_{VLO}</math> in GHz is
<center><math>f_{LO} = {\rm FSeqList}/2 + 21 {\rm[GHz]}</math>. (1)</center>

This discussion will follow the discussion in Appendix A of Liu et al. (2007), see Figure 1 below.
[[File:5.png|right|thumb|600px|Figure 1: Diagram showing the three downconversions.]]

As shown in Figure 1, a plane wave arrives later for the antenna on the left, so its fluctuating waveform is shifted by a phase , where is the continuously varying geometric delay required to track the source. The first downconversion by the variable LO inverts the frequencies on both antennas and shifts them by the oscillator frequency . The second downconversion by the fixed LO inverts and shifts the frequencies by in a similar manner. This produces an IF frequency in the range 600-1200 MHz. The final downconversion is done by the ADC, which does a final inversion of the frequencies and shifts them by . After digitization, an integer “course delay” rounded to the nearest digitizer clock step, is inserted into the right-hand antenna. After correlation (multiplication and averaging), the fast fluctuation involving t is eliminated, but the signal is left with a fluctuating phase
(2)
where is the non-integer “fine delay,” which must be applied on a channel-by-channel basis across the 600 MHz IF band, while the first term is constant over the band (for a given tuning frequency). The phase in equation (2) is to be subtracted from the phase of the baseline.

=== 2, Cross-Checks ===
To verify that the above is correct, first note that the frequency
(3)
is the IF frequency corresponding to RF frequency . As shown in the memo Documentation of Downconversion and Tuning, (see Figure 2, reproduced from that document) for an ADC clock frequency of 1200 MHz, we expect (blue numbers in Figure 2) an RF frequency of, say, 2.5 GHz, to be at IF frequency 50 MHz when tuned to the 2-2.5 GHz band (FSeqList = 3), while the other end of the band, 2.0 GHz, should be at 550 MHz (i.e. the IF band is inverted relative to the RF).

[[File:6.png|600px|right|thumb|Figure 2: Schematic representation of the third EOVSA downconversion by the digitizer. The filtered second IF band on the left, whose frequency scale is marked in black (in MHz), is mirrored and converted to the IF band on the right, marked in blue (in MHz). The 600 MHz-wide digitized bandpass is shown in green, while the narrower 500 MHz target bandpass is shown by the inner dashed lines on the right.]]

Using equation (1), the variable LO would be tuned to 22.5 GHz for this band, so:
,
.
The equation (3) works for any band, when and are changed appropriately.
Likewise, if the ADC clock frequency is 800 MHz, as it is at present, then the lower part of the band (0-200 MHz) is overlapped, and the upper part of the band (200-400 MHz) is direct relative to the RF (see Figure 3, reproduced from the earlier memo).

[[File:7.png|thumb|400px|left|Figure 3: Schematic representation of the third EOVSA downconversion by the digitizer, when the digitizer clock is at the non-ideal frequency of 800 MHz. The second IF band is shown in black (in MHz), while the mirrored IF band partially overlaps and extends to the left, marked in blue. The green block indicates the downconverted, digitized bandpass, whose scale is shown in blue (in MHz). The part of the band contaminated with overlapping is shown as the darker green hatched area.]]

In this case, for the same 2.0-2.5 GHz band 3 as the earlier example, we expect 2.0 GHz RF to be at 150 MHz IF, 2.15 GHz to be at 0 MHz IF, 2.3 GHz to be again at 150 MHz, and 2.5 GHz RF to be at 350 MHz. For these four cases, equation (2) gives:
,
, , .
Note that any RF frequency above 2.15 GHz results in a negative IF frequency, which, when aliased about zero, becomes the absolute value of the IF frequency.
We conclude that equation (3) is accurate for any ADC clock and RF frequency.
Looking now at equation (2), the first term is the phase variation associated with natural fringes, while the second term is the channel-dependent phase associated with the “fine delay” (the difference between integer-stepped “coarse delay” and the true geometric delay). Let us look at these terms and verify that they have the expected behavior. Let’s rewrite this as:
.
The first term, , is constant for a given band, and by definition constant over a 1-s period since delay steps can only happen on 1-s boundaries. In fact, this term can remain constant for several minutes for short baselines that are not changing projected length very fast. The term can grow very large, and has stepwise discontinuities since varies in “coarse delay” steps. Because ranges from 21.5-38 GHz, for the case of an 800 MHz ADC clock the frequency term ranges from 7.226 radians/ns to 110.898 radians/ns (414-6354 degrees/ns). Since the steps in occur in 1.25 ns steps for an 800 MHz ADC clock, this is 517.5-7942.5 degrees/step. Although this seems large, it agrees with my analysis detailed in section 2.1 Delay Tracking, in the memo EOVSA_Calibration. There I found a maximum fringe rate of 6.6 Hz. Taking 6354 degrees/ns, and maximum delay rate of 0.364 ns/s from that memo, I have (6354 degrees/ns) (0.364 ns/s) / (360 degrees) = 6.44 Hz. The slight discrepancy is due to the above numbers referring to a frequency of 17.650 GHz (see next paragraph), whereas the memo used 18 GHz. Applying the correction, I get a fringe rate of 6.58 Hz.
The second term, , can also be quite large. Since in general can range from 1/2 step (0.625 ns) to +1/2 step (0.625 ns), for an RF frequency of 18 GHz, ranges from -4050 to 4050 degrees. It is puzzling that the total range, 8100 degrees, is not quite the same as the max degrees/step of the natural fringe term (7942.5 degrees). Ah, but the frequency 17.650 GHz does yield an exact match, which corresponds to 0 MHz in the band-34 IF, according to equation (3).

Owens Valley Solar Arrays

2024-09-27T13:48:04Z

Dgary: /* Starting solar beamforming observations */

[[File:Eovsa1.png|border|text-top|800px]]

<big>[http://ovsa.njit.edu/ EOVSA] (Expanded Owens Valley Solar Array) is a solar-dedicated radio interferometer operated by the New Jersey Institute of Technology and serving as a '''National Science Foundation Geospace Facility'''. [[File:NSF.jpg|70px]]
<pre>Operation of EOVSA is supported by the National Science Foundation under Grant No. AGS-2130832. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. </pre>
This wiki serves as the site for EOVSA documentation. </big>

[[File:OVRO-LWA1.png|border|text-top|800px]]

<big>OVRO-LWA (Owens Valley Radio Observatory Long Wavelength Array) is an all-sky imager that has a new solar-dedicated spectroscopic imaging mode. OVRO-LWA is a multi-institutional collaboration led by Caltech. NJIT Solar Radio Group is leading its solar-mode development and science. At the bottom of this page are new links for that facility. </big>

== EOVSA Flare List ==

* [https://ovsa.njit.edu/flarelist Query EOVSA Flare list]
* List of EOVSA flares in separate years: [[2024]], [[2023]], [[2022]], [[2021]], [[2020]], [[2019]], [[2017]]

== Using EOVSA Data ==
* <big>[[EOVSA Data products]]</big>: An introduction to standard EOVSA spectrogram and spectral image products with example scripts for reading and plotting.
* <big>[[EOVSA Data Policy]]</big>: Policy for using EOVSA data products.
* <big>Analysis Software</big>: These are for in-depth use of EOVSA data (from calibrated visibilities) and tools for quantitative analysis.
** [https://github.com/suncasa/suncasa SunCASA] A wrapper around [https://casa.nrao.edu/ CASA (the Common Astronomy Software Applications package)] for synthesis imaging and visualizing solar spectral imaging data. CASA is one of the leading software tool for "supporting the data post-processing needs of the next generation of radio astronomical telescopes such as ALMA and VLA", an international effort led by the [https://public.nrao.edu/ National Radio Astronomy Observatory]. The current version of CASA uses Python (2.7) interface. More information about CASA can be found on [https://casa.nrao.edu/ NRAO's CASA website ]. Note, CASA is available ONLY on UNIX-BASED PLATFORMS (and therefore, so is SunCASA).
** [https://github.com/Gelu-Nita/GSFIT GSFIT] A IDL-widget(GUI)-based spectral fitting package called gsfit, which provides a user-friendly display of EOVSA image cubes and an interface to fast fitting codes (via platform-dependent shared-object libraries).
** [https://github.com/suncasa/pygsfit pyGSFIT] A Python-widget(pyQT)-based spectral fitting package, which provides a user-friendly display of EOVSA image cubes, spatially resolved spectra, and an interface to scipy-based fitting codes.
** [[Spectrogram Software]]
** [[Mapping Software]]
* <big>Data Analysis Guides</big>
** <big>[[EOVSA Data Analysis Tutorial 2022]]</big> and <big>[https://colab.research.google.com/drive/19NQb6Emb9HvKX4QHq9ZYCP3RM6nT7sDL#scrollTo=cLdDVptBGG-X EOVSA Workspace]</big> at [https://sphere.boulder.swri.edu/ SPHERE 2022 Workshop]
** <big>[https://colab.research.google.com/drive/1lSLLxgOG6b8kgu9Sk6kSKvrViyubnXG6?usp=sharing#scrollTo=xbXyyLmCFCGL EOVSA Data Analysis Tutorial at RHESSI 19 Workshop]</big>
** <big>[[EOVSA Data Analysis Tutorial]]</big> at [http://rhessi18.umn.edu/ RHESSI XVIII Workshop]
** [[Self-Calibrating Flare Data]] Example script and guides for self-calibrating EOVSA flare data (to be completed)


**[[IDB flare pipeline]] Tutorial to run the flare pipeline for quicklook images



* <big>EOVSA Modeling Guide</big>
**[[GX Simulator]]

* Other helpful links
** [https://casaguides.nrao.edu CASA Guides]
** [http://www.lmsal.com/solarsoft/ SolarSoft IDL]
** [http://www.atnf.csiro.au/computing/software/miriad/userguide/userhtml.html Miriad Guides]
** [https://sites.google.com/site/fgscodes/ Fast Gyrosynchrotron Codes (Alexey Kuznetsov's website)]
** [[Basic GitHub Tutorial]]


* <big>[[Full Disk Simulations]]</big>
* <big>[[All-Day Synthesis Issues]]</big>
* <big>[[Analyzing Pre-2017 Data]]</big>
* <big>[[Fixing Pipeline Problems pre-2021-Feb-07]]</big>

== EOVSA Documentation ==

* <big>General</big>
** [[Downconversion and Frequency Tuning]]
** [[Dealing with Radio Frequency Interference]]
** [[Switching between 200 MHz and 300 MHz Correlator]]
** [[Observing in "Fast" Mode]]

* <big>Computer-Network</big>
** [[Computing Systems]]
** [[Network]]

* <big>Control System</big>
** [[27-m Antenna Commands]]
** [[Schedule Commands]]
** [[Control Commands]]
** [[Attenuation and Level Control]]

* <big>Hardware</big>
** [[Hardware Overview]]
** [[2.1-m Antennas]]
** [[27-m Antennas]]

* <big>System Software</big>
** [[Calibration Database]]
** [[Stateframe Database]]
** [[Database Maintenance]]
** [[Create CASA measurement sets]]

* <big>Calibration</big>
**[[Calibration Overview]]
**[[Pointing Calibration]]
**[[Total Power Calibration]]
**[[System Gain Calibration]]
**[[Antenna Position]] (Baseline Calibration)
**[[Reference Gain Calibration]]
**[[Daily Gain Calibration]]
**[[Delay Calibration]]
**[[Bandpass Calibration]]
**[[Polarization Calibration]]
**[[Calibrator Survey]]
**[[Practical Calibration Tutorial]]

* <big>[[Starburst]]</big>

== System Software ==

* LabVIEW software
* Python code [https://github.com/dgary50/eovsa Github repository]
* [[Python3 Code Installation]]

== EOVSA Observing Log ==
[[2016 November]]; [[2016 December| December]]

[[2017 January]]; [[2017 February | February]]; [[2017 March | March]]; [[2017 April | April]]; [[2017 May | May]]; [[2017 June | June]];
[[2017 July | July]]; [[2017 August | August]]; [[2017 September | September]]; [[2017 October | October]]; [[2017 November | November]]; [[2017 December | December]]

[[2018 January]]; [[2018 February | February]]; [[2018 March | March]]; [[2018 April | April]]; [[2018 May | May]]; [[2018 June | June]];
[[2018 July | July]]; [[2018 August | August]]; [[2018 September | September]]; [[2018 October | October]]; [[2018 November | November]]; [[2018 December | December]]

[[2019 January]]; [[2019 February | February]]; [[2019 March | March]]; [[2019 April | April]]; [[2019 May | May]]; [[2019 June | June]];
[[2019 July | July]]; [[2019 August | August]]; [[2019 September | September]]; [[2019 October | October]]; [[2019 November | November]]; [[2019 December | December]]

[[2020 January]]; [[2020 February | February]]; [[2020 March | March]]; [[2020 April | April]]; [[2020 May | May]]; [[2020 June | June]];
[[2020 July | July]]; [[2020 August | August]]; [[2020 September | September]]; [[2020 October | October]]; [[2020 November | November]]; [[2020 December | December]]

[[2021 January]]; [[2021 February | February]]; [[2021 March | March]]; [[2021 April | April]]; [[2021 May | May]]; [[2021 June | June]];
[[2021 July | July]]; [[2021 August | August]]; [[2021 September | September]]; [[2021 October | October]]; [[2021 November | November]]; [[2021 December | December]]

[[2022 SQL Outage]]

[[2023 January]]; [[2023 February | February]]; [[2023 March | March]]; [[2023 April | April]]; [[2023 May | May]]; [[2023 June | June]];
[[2023 July | July]]; [[2023 August | August]]; [[2023 September | September]]; [[2023 October | October]]; [[2023 November | November]]; [[2023 December | December]]

[[2024 January]]; [[2024 February | February]]; [[2024 March | March]];[[2024 April | April]];[[2024 May |May]]; [[2024 June | June]]; [[2024 July | July]]; [[2024 August | August]];
[[2024 September | September]]

== SoD Observing Logs ==
* See [https://docs.google.com/document/d/1_iGnMRRrvb85Z0vT8-LzgQmCOKDSATEuQ0vTsn2C-dc/edit?usp=sharing SoD Routines] for detailed instructions for Scientist-on-Duty routines.
* 2024 [https://docs.google.com/document/d/1QDWw5y4HpcE7CSpzXwftMqQT4FDgNJj-6fRrgWrqdug/edit?usp=sharing May (and before that)], [https://docs.google.com/document/d/1Rh2gYBV2E454xVYEv8jx5IXKd1N2Z05ns4dhI2XCE08/edit?usp=sharing June], [https://docs.google.com/document/d/1beUpp6rgwjqSxKbuHzXIR9hhPrGyi0j-SjtEIeav9Vg/edit?usp=sharing July], [https://docs.google.com/document/d/1pSzUXW5gd-4cZAR-gglTUVM_J2UHMa4wYJ2AzD4cdEo/edit?usp=sharing August], [https://docs.google.com/document/d/18pArAP0kRDhXHbty_y3TtrygmWkC2oLn-UD7njIpRIo/edit?usp=sharing September], October, November, December

== Tohbans ==

[[Trouble Shooting Guide]]

[[Tohban Records]]

[[Owen's Notes]]

[[Caius' Notes]]

[[Tohban EOVSA Imaging Tutorial A-Z]]

[[Tohban OVRO-LWA Imaging Tutorial]]

[[Tohban Guide to Self Calibration and Imaging for EOVSA]]

[[Guide to Upgrade SolarSoft(SSW)]]

== EOVSA Publications ==
Here is a (partial) list of publications that utilize EOVSA data. See also the collection of EOVSA publications at [https://ui.adsabs.harvard.edu/public-libraries/eQ7HfPkySqydu-B8BCt6QQ this NASA/ADS Library].
; 2024
: Collier, H., Hayes, L. A., Yu, S., Battaglia, A. F., Ashfield, W., Polito, V., Harra, L. K., & Krucker, S. (2024), arXiv e-prints, arXiv:2402.10546. [https://ui.adsabs.harvard.edu/abs/2024arXiv240210546C “Localising pulsations in the hard X-ray and microwave emission of an X-class flare”]
: Saqri, J., Veronig, A. M., Battaglia, A. F., Dickson, E. C. M., Gary, D. E., & Krucker, S. (2024), Astronomy and Astrophysics, 683, A41. [https://ui.adsabs.harvard.edu/abs/2024A&A...683A..41S "Efficiency of solar microflares in accelerating electrons when rooted in a sunspot"]
; 2023
: Tan, B., Yan, Y., Huang, J., Zhang, Y., Tan, C., & Zhu, X. (2023), Advances in Space Research, 72, 5563. [https://ui.adsabs.harvard.edu/abs/2023AdSpR..72.5563T "The physics of solar spectral imaging observations in dm-cm wavelengths and the application on space weather"]

: Li, D., Li, Z., Shi, F., Su, Y., Chen, W., Yu, F., Li, C., Qiu, Y., Huang, Y., & Ning, Z. (2023), Astronomy and Astrophysics, 680, L15. [https://ui.adsabs.harvard.edu/abs/2023A&A...680L..15L "Observational signature of continuously operating drivers of decayless kink oscillation"]

: Wang, M., Chen, B., Yu, S., Gary, D. E., Lee, J., Wang, H., & Cohen, C. (2023), The Astrophysical Journal, 954, 32. [https://ui.adsabs.harvard.edu/abs/2023ApJ...954...32W "The Solar Origin of an In Situ Type III Radio Burst Event"]

: Gary, D. E. (2023), Annual Review of Astronomy and Astrophysics, 61, 427. [https://ui.adsabs.harvard.edu/abs/2023ARA&A..61..427G "New Insights from Imaging Spectroscopy of Solar Radio Emission"]

: Nita, G. M., Fleishman, G. D., Kuznetsov, A. A., Anfinogentov, S. A., Stupishin, A. G., Kontar, E. P., Schonfeld, S. J., Klimchuk, J. A., & Gary, D. E. (2023), The Astrophysical Journal Supplement Series, 267, 6. [https://ui.adsabs.harvard.edu/abs/2023ApJS..267....6N "Data-constrained Solar Modeling with GX Simulator"]

: Song, D.-C., Tian, J., Li, Y., Ding, M. D., Su, Y., Yu, S., Hong, J., Qiu, Y., Rao, S., Liu, X., Li, Q., Chen, X., Li, C., & Fang, C. (2023), The Astrophysical Journal, 952, L6. [https://ui.adsabs.harvard.edu/abs/2023ApJ...952L...6S "Spectral Observations and Modeling of a Solar White-light Flare Observed by CHASE"]

: Mondal, S., Chen, B., & Yu, S. (2023), The Astrophysical Journal, 949, 56. [https://ui.adsabs.harvard.edu/abs/2023ApJ...949...56M "Multifrequency Microwave Imaging of Weak Transients from the Quiet Solar Corona"]

: Kontar, E. P., Emslie, A. G., Motorina, G. G., & Dennis, B. R. (2023), The Astrophysical Journal, 947, L13. [https://ui.adsabs.harvard.edu/abs/2023ApJ...947L..13K "The Efficiency of Electron Acceleration during the Impulsive Phase of a Solar Flare"]

: Saqri, J., Veronig, A. M., Dickson, E. C. M., Podladchikova, T., Warmuth, A., Xiao, H., Gary, D. E., Battaglia, A. F., & Krucker, S. (2023), Astronomy and Astrophysics, 672, A23. [https://ui.adsabs.harvard.edu/abs/2023A&A...672A..23S "Multi-point study of the energy release and impulsive CME dynamics in an eruptive C7 flare"]
; 2022

: Kou, Y., Cheng, X., Wang, Y., Yu, S., Chen, B., Kontar, E. P., & Ding, M. (2022), Nature Communications, 13, 7680. [https://ui.adsabs.harvard.edu/abs/2022NatCo..13.7680K "Microwave imaging of quasi-periodic pulsations at flare current sheet"]

: Chertok, I. M. (2022), Monthly Notices of the Royal Astronomical Society, 517, 2709. [https://ui.adsabs.harvard.edu/abs/2022MNRAS.517.2709C "On some features of the solar proton event on 2021 October 28 - GLE73"]

: Lörinčík, J., Polito, V., De Pontieu, B., Yu, S., & Freij, N. (2022), Frontiers in Astronomy and Space Sciences, 9, 334. [https://ui.adsabs.harvard.edu/abs/2022FrASS...940945L "Rapid variations of Si IV spectra in a flare observed by interface region imaging spectrograph at a sub-second cadence"]

: Klein, K.-L., Musset, S., Vilmer, N., Briand, C., Krucker, S., Francesco Battaglia, A., Dresing, N., Palmroos, C., & Gary, D. E. (2022), Astronomy and Astrophysics, 663, A173. [https://ui.adsabs.harvard.edu/abs/2022A&A...663A.173K "The relativistic solar particle event on 28 October 2021: Evidence of particle acceleration within and escape from the solar corona"]

: Fleishman, G. D., Nita, G. M., Chen, B., Yu, S., & Gary, D. E. (2022), Nature, 606, 674. [https://ui.adsabs.harvard.edu/abs/2022Natur.606..674F "Solar flare accelerates nearly all electrons in a large coronal volume"]

: Li, X., Guo, F., Chen, B., Shen, C., & Glesener, L. (2022), The Astrophysical Journal, 932, 92. [https://ui.adsabs.harvard.edu/abs/2022ApJ...932...92L "Modeling Electron Acceleration and Transport in the Early Impulsive Phase of the 2017 September 10th Solar Flare"]

: Zhang, J., Chen, B., Yu, S., Tian, H., Wei, Y., Chen, H., Tan, G., Luo, Y., & Chen, X. (2022), The Astrophysical Journal, 932, 53. [https://ui.adsabs.harvard.edu/abs/2022ApJ...932...53Z "Implications for Additional Plasma Heating Driving the Extreme-ultraviolet Late Phase of a Solar Flare with Microwave Imaging Spectroscopy"]

: Liu, N., Jing, J., Xu, Y., & Wang, H. (2022), The Astrophysical Journal, 930, 154. [https://ui.adsabs.harvard.edu/abs/2022ApJ...930..154L "Multi-instrument Comparative Study of Temperature, Number Density, and Emission Measure during the Precursor Phase of a Solar Flare"]

: López, F. M., Giménez de Castro, C. G., Mandrini, C. H., Simões, P. J. A., Cristiani, G. D., Gary, D. E., Francile, C., & Démoulin, P. (2022), Astronomy and Astrophysics, 657, A51. [https://ui.adsabs.harvard.edu/abs/2022A&A...657A..51L "A solar flare driven by thermal conduction observed in mid-infrared"]

: Unverferth, J., & Longcope, D. (2021), The Astrophysical Journal, 923, 248. [https://ui.adsabs.harvard.edu/abs/2021ApJ...923..248U "Examining Flux Tube Interactions as a Cause of Sub-alfvénic Outflow"]
;2021

: Wei, Y., Chen, B., Yu, S., Wang, H., Jing, J., & Gary, D. E. (2021), The Astrophysical Journal, 923, 213. [https://ui.adsabs.harvard.edu/abs/2021ApJ...923..213W "Coronal Magnetic Field Measurements along a Partially Erupting Filament in a Solar Flare"]

: Jing, J., Inoue, S., Lee, J., Li, Q., Nita, G. M., Xu, Y., Liu, C., Gary, D. E., & Wang, H. (2021), The Astrophysical Journal, 922, 108. [https://ui.adsabs.harvard.edu/abs/2021ApJ...922..108J "Understanding the Initiation of the M2.4 Flare on 2017 July 14"]

: Battaglia, A. F., Saqri, J., Massa, P., Perracchione, E., Dickson, E. C. M., Xiao, H., Veronig, A. M., Warmuth, A., Battaglia, M., Hurford, G. J., Meuris, A., Limousin, O., Etesi, L., Maloney, S. A., Schwartz, R. A., Kuhar, M., Schuller, F., Senthamizh Pavai, V., Musset, S., Ryan, D. F., Kleint, L., Piana, M., Massone, A. M., Benvenuto, F., Sylwester, J., Litwicka, M., Stȩślicki, M., Mrozek, T., Vilmer, N., Fárník, F., Kašparová, J., Mann, G., Gallagher, P. T., Dennis, B. R., Csillaghy, A., Benz, A. O., & Krucker, S. (2021), Astronomy and Astrophysics, 656, A4. [https://ui.adsabs.harvard.edu/abs/2021A&A...656A...4B "STIX X-ray microflare observations during the Solar Orbiter commissioning phase"]

: Shaik, S. B., & Gary, D. E. (2021), The Astrophysical Journal, 919, 44. [https://ui.adsabs.harvard.edu/abs/2021ApJ...919...44S "Implications of Flat Optically Thick Microwave Spectra in Solar Flares for Source Size and Morphology"]

: Kocharov, L., Omodei, N., Mishev, A., Pesce-Rollins, M., Longo, F., Yu, S., Gary, D. E., Vainio, R., & Usoskin, I. (2021), The Astrophysical Journal, 915, 12. [https://ui.adsabs.harvard.edu/abs/2021ApJ...915...12K "Multiple Sources of Solar High-energy Protons"]

: Chen, B., Battaglia, M., Krucker, S., Reeves, K. K., & Glesener, L. (2021), The Astrophysical Journal, 908, L55. [https://ui.adsabs.harvard.edu/abs/2021ApJ...908L..55C "Energetic Electron Distribution of the Coronal Acceleration Region: First Results from Joint Microwave and Hard X-Ray Imaging Spectroscopy"]

: Chhabra, S., Gary, D. E., Hallinan, G., Anderson, M. M., Chen, B., Greenhill, L. J., & Price, D. C. (2021), The Astrophysical Journal, 906, 132. [https://ui.adsabs.harvard.edu/abs/2021ApJ...906..132C "Imaging Spectroscopy of CME-associated Solar Radio Bursts using OVRO-LWA"]
;2020 and earlier

: Reeves, K. K., Polito, V., Chen, B., Galan, G., Yu, S., Liu, W., & Li, G. (2020), The Astrophysical Journal, 905, 165. [https://ui.adsabs.harvard.edu/abs/2020ApJ...905..165R "Hot Plasma Flows and Oscillations in the Loop-top Region During the 2017 September 10 X8.2 Solar Flare"]

: Nindos, A. (2020), Frontiers in Astronomy and Space Sciences, 7, 57. [https://ui.adsabs.harvard.edu/abs/2020FrASS...7...57N "Incoherent Solar Radio Emission"]

: Yu, S., Chen, B., Reeves, K. K., Gary, D. E., Musset, S., Fleishman, G. D., Nita, G. M., & Glesener, L. (2020), The Astrophysical Journal, 900, 17. [https://ui.adsabs.harvard.edu/abs/2020ApJ...900...17Y "Magnetic Reconnection during the Post-impulsive Phase of a Long-duration Solar Flare: Bidirectional Outflows as a Cause of Microwave and X-Ray Bursts"]

: Chen, B., Yu, S., Reeves, K. K., & Gary, D. E. (2020), The Astrophysical Journal, 895, L50. [https://ui.adsabs.harvard.edu/abs/2020ApJ...895L..50C "Microwave Spectral Imaging of an Erupting Magnetic Flux Rope: Implications for the Standard Solar Flare Model in Three Dimensions"]

: Kuroda, N., Fleishman, G. D., Gary, D. E., Nita, G. M., Chen, B., & Yu, S. (2020), Frontiers in Astronomy and Space Sciences, 7, 22. [https://ui.adsabs.harvard.edu/abs/2020FrASS...7...22K "Evolution of Flare-accelerated Electrons Quantified by Spatially Resolved Analysis"]

: Glesener, L., Krucker, S., Duncan, J., Hannah, I. G., Grefenstette, B. W., Chen, B., Smith, D. M., White, S. M., & Hudson, H. (2020), The Astrophysical Journal, 891, L34. [https://ui.adsabs.harvard.edu/abs/2020ApJ...891L..34G "Accelerated Electrons Observed Down to <7 keV in a NuSTAR Solar Microflare"]

: Karlický, M., Chen, B., Gary, D. E., Kašparová, J., & Rybák, J. (2020), The Astrophysical Journal, 889, 72. [https://ui.adsabs.harvard.edu/abs/2020ApJ...889...72K "Drifting Pulsation Structure at the Very Beginning of the 2017 September 10 Limb Flare"]

: Fleishman, G. D., Gary, D. E., Chen, B., Kuroda, N., Yu, S., & Nita, G. M. (2020), Science, 367, 278. [https://ui.adsabs.harvard.edu/abs/2020Sci...367..278F "Decay of the coronal magnetic field can release sufficient energy to power a solar flare"]

: Chen, B., Shen, C., Gary, D. E., Reeves, K. K., Fleishman, G. D., Yu, S., Guo, F., Krucker, S., Lin, J., Nita, G. M., & Kong, X. (2020), Nature Astronomy, 4, 1140. [https://ui.adsabs.harvard.edu/abs/2020NatAs...4.1140C "Measurement of magnetic field and relativistic electrons along a solar flare current sheet"]

: Lee, J. (2018), Journal of Astronomy and Space Sciences, 35, 211. [https://ui.adsabs.harvard.edu/abs/2018JASS...35..211L "Analysis of Solar Microwave Burst Spectrum, I. Nonuniform Magnetic Field"]

: Gary, D. E., Bastian, T. S., Chen, B., Fleishman, G. D., & Glesener, L. (2018), Science with a Next Generation Very Large Array, 517, 99. [https://ui.adsabs.harvard.edu/abs/2018ASPC..517...99G "Radio Observations of Solar Flares"]

: Polito, V., Dudík, J., Kašparová, J., Dzifčáková, E., Reeves, K. K., Testa, P., & Chen, B. (2018), The Astrophysical Journal, 864, 63. [https://ui.adsabs.harvard.edu/abs/2018ApJ...864...63P "Broad Non-Gaussian Fe XXIV Line Profiles in the Impulsive Phase of the 2017 September 10 X8.3-class Flare Observed by Hinode/EIS"]

: Gary, D. E., Chen, B., Dennis, B. R., Fleishman, G. D., Hurford, G. J., Krucker, S., McTiernan, J. M., Nita, G. M., Shih, A. Y., White, S. M., & Yu, S. (2018), The Astrophysical Journal, 863, 83. [https://ui.adsabs.harvard.edu/abs/2018ApJ...863...83G "Microwave and Hard X-Ray Observations of the 2017 September 10 Solar Limb Flare"]

: Fleishman, G. D., Nita, G. M., Kuroda, N., Jia, S., Tong, K., Wen, R. R., & Zhizhuo, Z. (2018), The Astrophysical Journal, 859, 17. [https://ui.adsabs.harvard.edu/abs/2018ApJ...859...17F "Revealing the Evolution of Non-thermal Electrons in Solar Flares Using 3D Modeling"]

: Kuroda, N., Gary, D. E., Wang, H., Fleishman, G. D., Nita, G. M., & Jing, J. (2018), The Astrophysical Journal, 852, 32. [https://ui.adsabs.harvard.edu/abs/2018ApJ...852...32K "Three-dimensional Forward-fit Modeling of the Hard X-Ray and Microwave Emissions of the 2015 June 22 M6.5 Flare"]

: Wang, H., Liu, C., Ahn, K., Xu, Y., Jing, J., Deng, N., Huang, N., Liu, R., Kusano, K., Fleishman, G. D., Gary, D. E., & Cao, W. (2017), Nature Astronomy, 1, 0085. [https://ui.adsabs.harvard.edu/abs/2017NatAs...1E..85W "High-resolution observations of flare precursors in the low solar atmosphere"]

: Nita, G. M., Hickish, J., MacMahon, D., & Gary, D. E. (2016), Journal of Astronomical Instrumentation, 5, 1641009-7366. [https://ui.adsabs.harvard.edu/abs/2016JAI.....541009N "EOVSA Implementation of a Spectral Kurtosis Correlator for Transient Detection and Classification"]

: Nita, G. M., & Gary, D. E. (2016), Journal of Geophysical Research (Space Physics), 121, 7353. [https://ui.adsabs.harvard.edu/abs/2016JGRA..121.7353N "Measurement of duration and signal-to-noise ratio of astronomical transients using a Spectral Kurtosis spectrometer"]

: Wang, Z., Gary, D. E., Fleishman, G. D., & White, S. M. (2015), The Astrophysical Journal, 805, 93. [https://ui.adsabs.harvard.edu/abs/2015ApJ...805...93W "Coronal Magnetography of a Simulated Solar Active Region from Microwave Imaging Spectropolarimetry"]

: Gary, D. E., Fleishman, G. D., & Nita, G. M. (2013), Solar Physics, 288, 549. [https://ui.adsabs.harvard.edu/abs/2013SoPh..288..549G "Magnetography of Solar Flaring Loops with Microwave Imaging Spectropolarimetry"]

== VLA Flare List and Publications ==
See [http://www.ovsa.njit.edu/wiki/index.php/VLA_Data_Survey#List_of_Jansky_VLA_Solar_Observations this link] for a list of flare observations made by the [https://science.nrao.edu/facilities/vla/ Karl G. Jansky Very Large Array] (VLA). Below is a partial list of publications that utilize VLA solar data (see also [https://ui.adsabs.harvard.edu/public-libraries/ZwbjpLo9RS-viufWEoQ95Q this NASA/ADS Library]).
* [https://ui.adsabs.harvard.edu/abs/2022ApJ...940..137L/abstract Luo et al. (2022), ApJ, 940, 137] ''Multiple Regions of Nonthermal Quasiperiodic Pulsations during the Impulsive Phase of a Solar Flare''
* [https://ui.adsabs.harvard.edu/abs/2021ApJ...922..134B/abstract Battaglia et al. (2021), ApJ, 922, 134] ''Multiple Electron Acceleration Instances during a Series of Solar Microflares Observed Simultaneously at X-Rays and Microwaves''
* [https://ui.adsabs.harvard.edu/abs/2021ApJ...911....4L/abstract Luo et al. (2021), ApJ, 911, 4] ''Radio Spectral Imaging of an M8.4 Eruptive Solar Flare: Possible Evidence of a Termination Shock''
* [https://ui.adsabs.harvard.edu/abs/2021ApJ...910...40Z/abstract Zhang et al. (2021), ApJ, 910, 40] ''Multiwavelength Observations of the Formation and Eruption of a Complex Filament''
* [https://ui.adsabs.harvard.edu/abs/2020ApJ...904...94S/abstract Sharma et al. (2020), ApJ, 904, 94] ''Radio and X-Ray Observations of Short-lived Episodes of Electron Acceleration in a Solar Microflare''
* [https://ui.adsabs.harvard.edu/abs/2019ApJ...884...63C/abstract Chen et al. (2019), ApJ, 884, 63] ''Radio Spectroscopic Imaging of a Solar Flare Termination Shock: Split-band Feature as Evidence for Shock Compression''
* [https://ui.adsabs.harvard.edu/abs/2019ApJ...872...71Y/abstract Yu & Chen (2019), ApJ, 872, 71] ''Possible Detection of Subsecond-period Propagating Magnetohydrodynamics Waves in Post-reconnection Magnetic Loops during a Two-ribbon Solar Flare''
* [https://ui.adsabs.harvard.edu/abs/2018ApJ...866...62C/abstract Chen et al. (2018), ApJ, 866, 62] ''Magnetic Reconnection Null Points as the Origin of Semirelativistic Electron Beams in a Solar Jet
''
* [https://ui.adsabs.harvard.edu/abs/2017ApJ...848...77W/abstract Wang et al. (2016), ApJ, 848, 77] ''Dynamic Spectral Imaging of Decimetric Fiber Bursts in an Eruptive Solar Flare''
* [https://ui.adsabs.harvard.edu/abs/2015Sci...350.1238C/abstract Chen et al. (2015), Science, 350, 1238] ''Particle acceleration by a solar flare termination shock''
* [https://ui.adsabs.harvard.edu/abs/2014ApJ...794..149C/abstract Chen et al. (2014), ApJ, 794, 149] ''Direct Evidence of an Eruptive, Filament-hosting Magnetic Flux Rope Leading to a Fast Solar Coronal Mass Ejection''
* [https://ui.adsabs.harvard.edu/abs/2013ApJ...763L..21C/abstract Chen et al. (2013), ApJL, 763, 21] ''Tracing Electron Beams in the Sun's Corona with Radio Dynamic Imaging Spectroscopy''

==Radio Data from Around The Heliosphere==
* [http://ovsa.njit.edu//wiki/index.php/Radio_Data_from_Around_the_World#Radio_Data_Access '' Radio Data '']

=OVRO-LWA Solar-Dedicated Spectroscopic Imager=
The OVRO-LWA (Owens Valley Radio Observatory Long Wavelength Array) has recently been upgraded to include a solar-dedicated beam and two solar imaging modes (slow visibilities of 352 antennas with a 10-s cadence, and fast visibilities of 48 antennas with a 0.1-s cadence). The large collecting area and excellent calibration provide unprecedented high-sensitivity imaging of the quiet Sun and bursts. The array is currently in commissioning and observations are not yet continuous, but they are becoming more so. See the daily realtime data at http://ovsa.njit.edu/status.php for '''real-time display of the spectrogram and a selection of images''', both updated on a 1-min cadence.

==Solar-Dedicated Modes==
===Beamformer===
The beamformer uses the 256 core antennas to form a synthesized beam of more than 1 degree in size that tracks the Sun from sunrise to sunset. This permits a continuous record of the full-Stokes total flux (without spatial resolution) of the Sun (a dynamic spectrum) with 24 kHz frequency resolution (3072 frequencies from 15-90 MHz) and as low as 1 ms time resolution.

===Slow Visibility Imaging===
In this mode, the entire 352-element array is interferometrically correlated to provide visibilities for imaging at all 3072 frequencies at 10-s time resolution. This is ideal for imaging quiet Sun and slowly-varying emission such as coronal mass ejections and active region variability.

===Fast Visibility Imaging===
In this mode, a subset of 48 antennas (chosen to include mainly outer antennas to maintain good spatial resolution) is interferometrically correlated to provide visibilities for imaging at 768 frequencies (96 kHz frequency resolution) at 0.1-s time resolution. This is ideal for imaging rapidly varying emission such as type II and type III bursts as well as many other solar spectral fine structures.

==Inital Data Access==
In its current commissioning state, we try to run the beamformer and imaging pipeline every day in real-time since November 2023 (no latency for beamforming spectrograms and 5-10 min latency for images). Quicklook real-time spectrograms/images can be accessed from http://ovsa.njit.edu/status.php. To access data from previous days, use the following links (replace yyyymmdd with the date you desire):
* Quicklook beamformer total-power spectrograms: http://ovsa.njit.edu/lwa-data/1min_spectra/yyyymmdd/. Check this link for additional daily plots [[Daily OVRO-LWA Beamformer Data]].
* Quicklook multi-frequency movies at 1-min cadence: http://ovsa.njit.edu/lwa-data/1min_images/yyyymmdd/movie_yyyy-mm-dd.html

Note our pipeline processing development is still in the early phase. For example, absolute flux calibrations have not been done for the beamformer spectrograms. Also, artificial effects (including ionospheric refraction effects) are present in the images that cause distortions/shifts. We caution interested users only to consider them for quick-look purposes at this point. Please contact the EOVSA PIs (Dale Gary, Bin Chen) if you intend to use them for science.

==Operation Notes==
===Starting solar beamforming observations===
* Log into lwacalim10 (this is the only node that allows submissions)
* Activate the deployment conda environment
<pre> conda activate deployment </pre>
* Check what schedules are there
<pre>
lwaobserving show-schedule
</pre>
* Submit the schedule for the next 7 days (note that sdf files are written to /tmp/solar_<date>_<time>.sdf and will be owned by you).
<pre>
ipython
cd /home/dgary
import make_solar_sdf
make_solar_sdf.multiday_obs(ndays=7)
</pre>
* Calibrate the beam (if needed, using the same Python session)
<pre>
from mnc import control
con=control.Controller('/opt/devel/dgary/lwa_config_calim_std.yaml')
con.configure_xengine(['dr2'], calibratebeams=True)
</pre>
If the beam is already calibrated, the con.configure_xengine command will say that and return immediately. If for any reason you want to override the current calibration, instead type
<pre>
con.configure_xengine(['dr2'], calibratebeams=True, force=True)
</pre>

===Starting slow and fast visibility recorders ===
* Log into lwacalim10
* Check the recorder status by going to http://localhost:5006/LWA_dashboard
* Activate the environment and configure
<pre>
conda activate deployment
ipython
cd /home/pipeline/proj/lwa-shell/mnc_python/
from mnc import control
con=control.Controller('/opt/devel/dgary/lwa_config_calim_std.yaml')
</pre>
* Start the recorders
<pre>
con.start_dr(['drvs', 'drfv'])
</pre>
* Check the recorder status in command line
<pre>
con.status_dr()
</pre>

Owens Valley Solar Arrays

2024-09-27T13:44:06Z

Dgary: /* Starting solar beamforming observations */

[[File:Eovsa1.png|border|text-top|800px]]

<big>[http://ovsa.njit.edu/ EOVSA] (Expanded Owens Valley Solar Array) is a solar-dedicated radio interferometer operated by the New Jersey Institute of Technology and serving as a '''National Science Foundation Geospace Facility'''. [[File:NSF.jpg|70px]]
<pre>Operation of EOVSA is supported by the National Science Foundation under Grant No. AGS-2130832. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. </pre>
This wiki serves as the site for EOVSA documentation. </big>

[[File:OVRO-LWA1.png|border|text-top|800px]]

<big>OVRO-LWA (Owens Valley Radio Observatory Long Wavelength Array) is an all-sky imager that has a new solar-dedicated spectroscopic imaging mode. OVRO-LWA is a multi-institutional collaboration led by Caltech. NJIT Solar Radio Group is leading its solar-mode development and science. At the bottom of this page are new links for that facility. </big>

== EOVSA Flare List ==

* [https://ovsa.njit.edu/flarelist Query EOVSA Flare list]
* List of EOVSA flares in separate years: [[2024]], [[2023]], [[2022]], [[2021]], [[2020]], [[2019]], [[2017]]

== Using EOVSA Data ==
* <big>[[EOVSA Data products]]</big>: An introduction to standard EOVSA spectrogram and spectral image products with example scripts for reading and plotting.
* <big>[[EOVSA Data Policy]]</big>: Policy for using EOVSA data products.
* <big>Analysis Software</big>: These are for in-depth use of EOVSA data (from calibrated visibilities) and tools for quantitative analysis.
** [https://github.com/suncasa/suncasa SunCASA] A wrapper around [https://casa.nrao.edu/ CASA (the Common Astronomy Software Applications package)] for synthesis imaging and visualizing solar spectral imaging data. CASA is one of the leading software tool for "supporting the data post-processing needs of the next generation of radio astronomical telescopes such as ALMA and VLA", an international effort led by the [https://public.nrao.edu/ National Radio Astronomy Observatory]. The current version of CASA uses Python (2.7) interface. More information about CASA can be found on [https://casa.nrao.edu/ NRAO's CASA website ]. Note, CASA is available ONLY on UNIX-BASED PLATFORMS (and therefore, so is SunCASA).
** [https://github.com/Gelu-Nita/GSFIT GSFIT] A IDL-widget(GUI)-based spectral fitting package called gsfit, which provides a user-friendly display of EOVSA image cubes and an interface to fast fitting codes (via platform-dependent shared-object libraries).
** [https://github.com/suncasa/pygsfit pyGSFIT] A Python-widget(pyQT)-based spectral fitting package, which provides a user-friendly display of EOVSA image cubes, spatially resolved spectra, and an interface to scipy-based fitting codes.
** [[Spectrogram Software]]
** [[Mapping Software]]
* <big>Data Analysis Guides</big>
** <big>[[EOVSA Data Analysis Tutorial 2022]]</big> and <big>[https://colab.research.google.com/drive/19NQb6Emb9HvKX4QHq9ZYCP3RM6nT7sDL#scrollTo=cLdDVptBGG-X EOVSA Workspace]</big> at [https://sphere.boulder.swri.edu/ SPHERE 2022 Workshop]
** <big>[https://colab.research.google.com/drive/1lSLLxgOG6b8kgu9Sk6kSKvrViyubnXG6?usp=sharing#scrollTo=xbXyyLmCFCGL EOVSA Data Analysis Tutorial at RHESSI 19 Workshop]</big>
** <big>[[EOVSA Data Analysis Tutorial]]</big> at [http://rhessi18.umn.edu/ RHESSI XVIII Workshop]
** [[Self-Calibrating Flare Data]] Example script and guides for self-calibrating EOVSA flare data (to be completed)


**[[IDB flare pipeline]] Tutorial to run the flare pipeline for quicklook images



* <big>EOVSA Modeling Guide</big>
**[[GX Simulator]]

* Other helpful links
** [https://casaguides.nrao.edu CASA Guides]
** [http://www.lmsal.com/solarsoft/ SolarSoft IDL]
** [http://www.atnf.csiro.au/computing/software/miriad/userguide/userhtml.html Miriad Guides]
** [https://sites.google.com/site/fgscodes/ Fast Gyrosynchrotron Codes (Alexey Kuznetsov's website)]
** [[Basic GitHub Tutorial]]


* <big>[[Full Disk Simulations]]</big>
* <big>[[All-Day Synthesis Issues]]</big>
* <big>[[Analyzing Pre-2017 Data]]</big>
* <big>[[Fixing Pipeline Problems pre-2021-Feb-07]]</big>

== EOVSA Documentation ==

* <big>General</big>
** [[Downconversion and Frequency Tuning]]
** [[Dealing with Radio Frequency Interference]]
** [[Switching between 200 MHz and 300 MHz Correlator]]
** [[Observing in "Fast" Mode]]

* <big>Computer-Network</big>
** [[Computing Systems]]
** [[Network]]

* <big>Control System</big>
** [[27-m Antenna Commands]]
** [[Schedule Commands]]
** [[Control Commands]]
** [[Attenuation and Level Control]]

* <big>Hardware</big>
** [[Hardware Overview]]
** [[2.1-m Antennas]]
** [[27-m Antennas]]

* <big>System Software</big>
** [[Calibration Database]]
** [[Stateframe Database]]
** [[Database Maintenance]]
** [[Create CASA measurement sets]]

* <big>Calibration</big>
**[[Calibration Overview]]
**[[Pointing Calibration]]
**[[Total Power Calibration]]
**[[System Gain Calibration]]
**[[Antenna Position]] (Baseline Calibration)
**[[Reference Gain Calibration]]
**[[Daily Gain Calibration]]
**[[Delay Calibration]]
**[[Bandpass Calibration]]
**[[Polarization Calibration]]
**[[Calibrator Survey]]
**[[Practical Calibration Tutorial]]

* <big>[[Starburst]]</big>

== System Software ==

* LabVIEW software
* Python code [https://github.com/dgary50/eovsa Github repository]
* [[Python3 Code Installation]]

== EOVSA Observing Log ==
[[2016 November]]; [[2016 December| December]]

[[2017 January]]; [[2017 February | February]]; [[2017 March | March]]; [[2017 April | April]]; [[2017 May | May]]; [[2017 June | June]];
[[2017 July | July]]; [[2017 August | August]]; [[2017 September | September]]; [[2017 October | October]]; [[2017 November | November]]; [[2017 December | December]]

[[2018 January]]; [[2018 February | February]]; [[2018 March | March]]; [[2018 April | April]]; [[2018 May | May]]; [[2018 June | June]];
[[2018 July | July]]; [[2018 August | August]]; [[2018 September | September]]; [[2018 October | October]]; [[2018 November | November]]; [[2018 December | December]]

[[2019 January]]; [[2019 February | February]]; [[2019 March | March]]; [[2019 April | April]]; [[2019 May | May]]; [[2019 June | June]];
[[2019 July | July]]; [[2019 August | August]]; [[2019 September | September]]; [[2019 October | October]]; [[2019 November | November]]; [[2019 December | December]]

[[2020 January]]; [[2020 February | February]]; [[2020 March | March]]; [[2020 April | April]]; [[2020 May | May]]; [[2020 June | June]];
[[2020 July | July]]; [[2020 August | August]]; [[2020 September | September]]; [[2020 October | October]]; [[2020 November | November]]; [[2020 December | December]]

[[2021 January]]; [[2021 February | February]]; [[2021 March | March]]; [[2021 April | April]]; [[2021 May | May]]; [[2021 June | June]];
[[2021 July | July]]; [[2021 August | August]]; [[2021 September | September]]; [[2021 October | October]]; [[2021 November | November]]; [[2021 December | December]]

[[2022 SQL Outage]]

[[2023 January]]; [[2023 February | February]]; [[2023 March | March]]; [[2023 April | April]]; [[2023 May | May]]; [[2023 June | June]];
[[2023 July | July]]; [[2023 August | August]]; [[2023 September | September]]; [[2023 October | October]]; [[2023 November | November]]; [[2023 December | December]]

[[2024 January]]; [[2024 February | February]]; [[2024 March | March]];[[2024 April | April]];[[2024 May |May]]; [[2024 June | June]]; [[2024 July | July]]; [[2024 August | August]];
[[2024 September | September]]

== SoD Observing Logs ==
* See [https://docs.google.com/document/d/1_iGnMRRrvb85Z0vT8-LzgQmCOKDSATEuQ0vTsn2C-dc/edit?usp=sharing SoD Routines] for detailed instructions for Scientist-on-Duty routines.
* 2024 [https://docs.google.com/document/d/1QDWw5y4HpcE7CSpzXwftMqQT4FDgNJj-6fRrgWrqdug/edit?usp=sharing May (and before that)], [https://docs.google.com/document/d/1Rh2gYBV2E454xVYEv8jx5IXKd1N2Z05ns4dhI2XCE08/edit?usp=sharing June], [https://docs.google.com/document/d/1beUpp6rgwjqSxKbuHzXIR9hhPrGyi0j-SjtEIeav9Vg/edit?usp=sharing July], [https://docs.google.com/document/d/1pSzUXW5gd-4cZAR-gglTUVM_J2UHMa4wYJ2AzD4cdEo/edit?usp=sharing August], [https://docs.google.com/document/d/18pArAP0kRDhXHbty_y3TtrygmWkC2oLn-UD7njIpRIo/edit?usp=sharing September], October, November, December

== Tohbans ==

[[Trouble Shooting Guide]]

[[Tohban Records]]

[[Owen's Notes]]

[[Caius' Notes]]

[[Tohban EOVSA Imaging Tutorial A-Z]]

[[Tohban OVRO-LWA Imaging Tutorial]]

[[Tohban Guide to Self Calibration and Imaging for EOVSA]]

[[Guide to Upgrade SolarSoft(SSW)]]

== EOVSA Publications ==
Here is a (partial) list of publications that utilize EOVSA data. See also the collection of EOVSA publications at [https://ui.adsabs.harvard.edu/public-libraries/eQ7HfPkySqydu-B8BCt6QQ this NASA/ADS Library].
; 2024
: Collier, H., Hayes, L. A., Yu, S., Battaglia, A. F., Ashfield, W., Polito, V., Harra, L. K., & Krucker, S. (2024), arXiv e-prints, arXiv:2402.10546. [https://ui.adsabs.harvard.edu/abs/2024arXiv240210546C “Localising pulsations in the hard X-ray and microwave emission of an X-class flare”]
: Saqri, J., Veronig, A. M., Battaglia, A. F., Dickson, E. C. M., Gary, D. E., & Krucker, S. (2024), Astronomy and Astrophysics, 683, A41. [https://ui.adsabs.harvard.edu/abs/2024A&A...683A..41S "Efficiency of solar microflares in accelerating electrons when rooted in a sunspot"]
; 2023
: Tan, B., Yan, Y., Huang, J., Zhang, Y., Tan, C., & Zhu, X. (2023), Advances in Space Research, 72, 5563. [https://ui.adsabs.harvard.edu/abs/2023AdSpR..72.5563T "The physics of solar spectral imaging observations in dm-cm wavelengths and the application on space weather"]

: Li, D., Li, Z., Shi, F., Su, Y., Chen, W., Yu, F., Li, C., Qiu, Y., Huang, Y., & Ning, Z. (2023), Astronomy and Astrophysics, 680, L15. [https://ui.adsabs.harvard.edu/abs/2023A&A...680L..15L "Observational signature of continuously operating drivers of decayless kink oscillation"]

: Wang, M., Chen, B., Yu, S., Gary, D. E., Lee, J., Wang, H., & Cohen, C. (2023), The Astrophysical Journal, 954, 32. [https://ui.adsabs.harvard.edu/abs/2023ApJ...954...32W "The Solar Origin of an In Situ Type III Radio Burst Event"]

: Gary, D. E. (2023), Annual Review of Astronomy and Astrophysics, 61, 427. [https://ui.adsabs.harvard.edu/abs/2023ARA&A..61..427G "New Insights from Imaging Spectroscopy of Solar Radio Emission"]

: Nita, G. M., Fleishman, G. D., Kuznetsov, A. A., Anfinogentov, S. A., Stupishin, A. G., Kontar, E. P., Schonfeld, S. J., Klimchuk, J. A., & Gary, D. E. (2023), The Astrophysical Journal Supplement Series, 267, 6. [https://ui.adsabs.harvard.edu/abs/2023ApJS..267....6N "Data-constrained Solar Modeling with GX Simulator"]

: Song, D.-C., Tian, J., Li, Y., Ding, M. D., Su, Y., Yu, S., Hong, J., Qiu, Y., Rao, S., Liu, X., Li, Q., Chen, X., Li, C., & Fang, C. (2023), The Astrophysical Journal, 952, L6. [https://ui.adsabs.harvard.edu/abs/2023ApJ...952L...6S "Spectral Observations and Modeling of a Solar White-light Flare Observed by CHASE"]

: Mondal, S., Chen, B., & Yu, S. (2023), The Astrophysical Journal, 949, 56. [https://ui.adsabs.harvard.edu/abs/2023ApJ...949...56M "Multifrequency Microwave Imaging of Weak Transients from the Quiet Solar Corona"]

: Kontar, E. P., Emslie, A. G., Motorina, G. G., & Dennis, B. R. (2023), The Astrophysical Journal, 947, L13. [https://ui.adsabs.harvard.edu/abs/2023ApJ...947L..13K "The Efficiency of Electron Acceleration during the Impulsive Phase of a Solar Flare"]

: Saqri, J., Veronig, A. M., Dickson, E. C. M., Podladchikova, T., Warmuth, A., Xiao, H., Gary, D. E., Battaglia, A. F., & Krucker, S. (2023), Astronomy and Astrophysics, 672, A23. [https://ui.adsabs.harvard.edu/abs/2023A&A...672A..23S "Multi-point study of the energy release and impulsive CME dynamics in an eruptive C7 flare"]
; 2022

: Kou, Y., Cheng, X., Wang, Y., Yu, S., Chen, B., Kontar, E. P., & Ding, M. (2022), Nature Communications, 13, 7680. [https://ui.adsabs.harvard.edu/abs/2022NatCo..13.7680K "Microwave imaging of quasi-periodic pulsations at flare current sheet"]

: Chertok, I. M. (2022), Monthly Notices of the Royal Astronomical Society, 517, 2709. [https://ui.adsabs.harvard.edu/abs/2022MNRAS.517.2709C "On some features of the solar proton event on 2021 October 28 - GLE73"]

: Lörinčík, J., Polito, V., De Pontieu, B., Yu, S., & Freij, N. (2022), Frontiers in Astronomy and Space Sciences, 9, 334. [https://ui.adsabs.harvard.edu/abs/2022FrASS...940945L "Rapid variations of Si IV spectra in a flare observed by interface region imaging spectrograph at a sub-second cadence"]

: Klein, K.-L., Musset, S., Vilmer, N., Briand, C., Krucker, S., Francesco Battaglia, A., Dresing, N., Palmroos, C., & Gary, D. E. (2022), Astronomy and Astrophysics, 663, A173. [https://ui.adsabs.harvard.edu/abs/2022A&A...663A.173K "The relativistic solar particle event on 28 October 2021: Evidence of particle acceleration within and escape from the solar corona"]

: Fleishman, G. D., Nita, G. M., Chen, B., Yu, S., & Gary, D. E. (2022), Nature, 606, 674. [https://ui.adsabs.harvard.edu/abs/2022Natur.606..674F "Solar flare accelerates nearly all electrons in a large coronal volume"]

: Li, X., Guo, F., Chen, B., Shen, C., & Glesener, L. (2022), The Astrophysical Journal, 932, 92. [https://ui.adsabs.harvard.edu/abs/2022ApJ...932...92L "Modeling Electron Acceleration and Transport in the Early Impulsive Phase of the 2017 September 10th Solar Flare"]

: Zhang, J., Chen, B., Yu, S., Tian, H., Wei, Y., Chen, H., Tan, G., Luo, Y., & Chen, X. (2022), The Astrophysical Journal, 932, 53. [https://ui.adsabs.harvard.edu/abs/2022ApJ...932...53Z "Implications for Additional Plasma Heating Driving the Extreme-ultraviolet Late Phase of a Solar Flare with Microwave Imaging Spectroscopy"]

: Liu, N., Jing, J., Xu, Y., & Wang, H. (2022), The Astrophysical Journal, 930, 154. [https://ui.adsabs.harvard.edu/abs/2022ApJ...930..154L "Multi-instrument Comparative Study of Temperature, Number Density, and Emission Measure during the Precursor Phase of a Solar Flare"]

: López, F. M., Giménez de Castro, C. G., Mandrini, C. H., Simões, P. J. A., Cristiani, G. D., Gary, D. E., Francile, C., & Démoulin, P. (2022), Astronomy and Astrophysics, 657, A51. [https://ui.adsabs.harvard.edu/abs/2022A&A...657A..51L "A solar flare driven by thermal conduction observed in mid-infrared"]

: Unverferth, J., & Longcope, D. (2021), The Astrophysical Journal, 923, 248. [https://ui.adsabs.harvard.edu/abs/2021ApJ...923..248U "Examining Flux Tube Interactions as a Cause of Sub-alfvénic Outflow"]
;2021

: Wei, Y., Chen, B., Yu, S., Wang, H., Jing, J., & Gary, D. E. (2021), The Astrophysical Journal, 923, 213. [https://ui.adsabs.harvard.edu/abs/2021ApJ...923..213W "Coronal Magnetic Field Measurements along a Partially Erupting Filament in a Solar Flare"]

: Jing, J., Inoue, S., Lee, J., Li, Q., Nita, G. M., Xu, Y., Liu, C., Gary, D. E., & Wang, H. (2021), The Astrophysical Journal, 922, 108. [https://ui.adsabs.harvard.edu/abs/2021ApJ...922..108J "Understanding the Initiation of the M2.4 Flare on 2017 July 14"]

: Battaglia, A. F., Saqri, J., Massa, P., Perracchione, E., Dickson, E. C. M., Xiao, H., Veronig, A. M., Warmuth, A., Battaglia, M., Hurford, G. J., Meuris, A., Limousin, O., Etesi, L., Maloney, S. A., Schwartz, R. A., Kuhar, M., Schuller, F., Senthamizh Pavai, V., Musset, S., Ryan, D. F., Kleint, L., Piana, M., Massone, A. M., Benvenuto, F., Sylwester, J., Litwicka, M., Stȩślicki, M., Mrozek, T., Vilmer, N., Fárník, F., Kašparová, J., Mann, G., Gallagher, P. T., Dennis, B. R., Csillaghy, A., Benz, A. O., & Krucker, S. (2021), Astronomy and Astrophysics, 656, A4. [https://ui.adsabs.harvard.edu/abs/2021A&A...656A...4B "STIX X-ray microflare observations during the Solar Orbiter commissioning phase"]

: Shaik, S. B., & Gary, D. E. (2021), The Astrophysical Journal, 919, 44. [https://ui.adsabs.harvard.edu/abs/2021ApJ...919...44S "Implications of Flat Optically Thick Microwave Spectra in Solar Flares for Source Size and Morphology"]

: Kocharov, L., Omodei, N., Mishev, A., Pesce-Rollins, M., Longo, F., Yu, S., Gary, D. E., Vainio, R., & Usoskin, I. (2021), The Astrophysical Journal, 915, 12. [https://ui.adsabs.harvard.edu/abs/2021ApJ...915...12K "Multiple Sources of Solar High-energy Protons"]

: Chen, B., Battaglia, M., Krucker, S., Reeves, K. K., & Glesener, L. (2021), The Astrophysical Journal, 908, L55. [https://ui.adsabs.harvard.edu/abs/2021ApJ...908L..55C "Energetic Electron Distribution of the Coronal Acceleration Region: First Results from Joint Microwave and Hard X-Ray Imaging Spectroscopy"]

: Chhabra, S., Gary, D. E., Hallinan, G., Anderson, M. M., Chen, B., Greenhill, L. J., & Price, D. C. (2021), The Astrophysical Journal, 906, 132. [https://ui.adsabs.harvard.edu/abs/2021ApJ...906..132C "Imaging Spectroscopy of CME-associated Solar Radio Bursts using OVRO-LWA"]
;2020 and earlier

: Reeves, K. K., Polito, V., Chen, B., Galan, G., Yu, S., Liu, W., & Li, G. (2020), The Astrophysical Journal, 905, 165. [https://ui.adsabs.harvard.edu/abs/2020ApJ...905..165R "Hot Plasma Flows and Oscillations in the Loop-top Region During the 2017 September 10 X8.2 Solar Flare"]

: Nindos, A. (2020), Frontiers in Astronomy and Space Sciences, 7, 57. [https://ui.adsabs.harvard.edu/abs/2020FrASS...7...57N "Incoherent Solar Radio Emission"]

: Yu, S., Chen, B., Reeves, K. K., Gary, D. E., Musset, S., Fleishman, G. D., Nita, G. M., & Glesener, L. (2020), The Astrophysical Journal, 900, 17. [https://ui.adsabs.harvard.edu/abs/2020ApJ...900...17Y "Magnetic Reconnection during the Post-impulsive Phase of a Long-duration Solar Flare: Bidirectional Outflows as a Cause of Microwave and X-Ray Bursts"]

: Chen, B., Yu, S., Reeves, K. K., & Gary, D. E. (2020), The Astrophysical Journal, 895, L50. [https://ui.adsabs.harvard.edu/abs/2020ApJ...895L..50C "Microwave Spectral Imaging of an Erupting Magnetic Flux Rope: Implications for the Standard Solar Flare Model in Three Dimensions"]

: Kuroda, N., Fleishman, G. D., Gary, D. E., Nita, G. M., Chen, B., & Yu, S. (2020), Frontiers in Astronomy and Space Sciences, 7, 22. [https://ui.adsabs.harvard.edu/abs/2020FrASS...7...22K "Evolution of Flare-accelerated Electrons Quantified by Spatially Resolved Analysis"]

: Glesener, L., Krucker, S., Duncan, J., Hannah, I. G., Grefenstette, B. W., Chen, B., Smith, D. M., White, S. M., & Hudson, H. (2020), The Astrophysical Journal, 891, L34. [https://ui.adsabs.harvard.edu/abs/2020ApJ...891L..34G "Accelerated Electrons Observed Down to <7 keV in a NuSTAR Solar Microflare"]

: Karlický, M., Chen, B., Gary, D. E., Kašparová, J., & Rybák, J. (2020), The Astrophysical Journal, 889, 72. [https://ui.adsabs.harvard.edu/abs/2020ApJ...889...72K "Drifting Pulsation Structure at the Very Beginning of the 2017 September 10 Limb Flare"]

: Fleishman, G. D., Gary, D. E., Chen, B., Kuroda, N., Yu, S., & Nita, G. M. (2020), Science, 367, 278. [https://ui.adsabs.harvard.edu/abs/2020Sci...367..278F "Decay of the coronal magnetic field can release sufficient energy to power a solar flare"]

: Chen, B., Shen, C., Gary, D. E., Reeves, K. K., Fleishman, G. D., Yu, S., Guo, F., Krucker, S., Lin, J., Nita, G. M., & Kong, X. (2020), Nature Astronomy, 4, 1140. [https://ui.adsabs.harvard.edu/abs/2020NatAs...4.1140C "Measurement of magnetic field and relativistic electrons along a solar flare current sheet"]

: Lee, J. (2018), Journal of Astronomy and Space Sciences, 35, 211. [https://ui.adsabs.harvard.edu/abs/2018JASS...35..211L "Analysis of Solar Microwave Burst Spectrum, I. Nonuniform Magnetic Field"]

: Gary, D. E., Bastian, T. S., Chen, B., Fleishman, G. D., & Glesener, L. (2018), Science with a Next Generation Very Large Array, 517, 99. [https://ui.adsabs.harvard.edu/abs/2018ASPC..517...99G "Radio Observations of Solar Flares"]

: Polito, V., Dudík, J., Kašparová, J., Dzifčáková, E., Reeves, K. K., Testa, P., & Chen, B. (2018), The Astrophysical Journal, 864, 63. [https://ui.adsabs.harvard.edu/abs/2018ApJ...864...63P "Broad Non-Gaussian Fe XXIV Line Profiles in the Impulsive Phase of the 2017 September 10 X8.3-class Flare Observed by Hinode/EIS"]

: Gary, D. E., Chen, B., Dennis, B. R., Fleishman, G. D., Hurford, G. J., Krucker, S., McTiernan, J. M., Nita, G. M., Shih, A. Y., White, S. M., & Yu, S. (2018), The Astrophysical Journal, 863, 83. [https://ui.adsabs.harvard.edu/abs/2018ApJ...863...83G "Microwave and Hard X-Ray Observations of the 2017 September 10 Solar Limb Flare"]

: Fleishman, G. D., Nita, G. M., Kuroda, N., Jia, S., Tong, K., Wen, R. R., & Zhizhuo, Z. (2018), The Astrophysical Journal, 859, 17. [https://ui.adsabs.harvard.edu/abs/2018ApJ...859...17F "Revealing the Evolution of Non-thermal Electrons in Solar Flares Using 3D Modeling"]

: Kuroda, N., Gary, D. E., Wang, H., Fleishman, G. D., Nita, G. M., & Jing, J. (2018), The Astrophysical Journal, 852, 32. [https://ui.adsabs.harvard.edu/abs/2018ApJ...852...32K "Three-dimensional Forward-fit Modeling of the Hard X-Ray and Microwave Emissions of the 2015 June 22 M6.5 Flare"]

: Wang, H., Liu, C., Ahn, K., Xu, Y., Jing, J., Deng, N., Huang, N., Liu, R., Kusano, K., Fleishman, G. D., Gary, D. E., & Cao, W. (2017), Nature Astronomy, 1, 0085. [https://ui.adsabs.harvard.edu/abs/2017NatAs...1E..85W "High-resolution observations of flare precursors in the low solar atmosphere"]

: Nita, G. M., Hickish, J., MacMahon, D., & Gary, D. E. (2016), Journal of Astronomical Instrumentation, 5, 1641009-7366. [https://ui.adsabs.harvard.edu/abs/2016JAI.....541009N "EOVSA Implementation of a Spectral Kurtosis Correlator for Transient Detection and Classification"]

: Nita, G. M., & Gary, D. E. (2016), Journal of Geophysical Research (Space Physics), 121, 7353. [https://ui.adsabs.harvard.edu/abs/2016JGRA..121.7353N "Measurement of duration and signal-to-noise ratio of astronomical transients using a Spectral Kurtosis spectrometer"]

: Wang, Z., Gary, D. E., Fleishman, G. D., & White, S. M. (2015), The Astrophysical Journal, 805, 93. [https://ui.adsabs.harvard.edu/abs/2015ApJ...805...93W "Coronal Magnetography of a Simulated Solar Active Region from Microwave Imaging Spectropolarimetry"]

: Gary, D. E., Fleishman, G. D., & Nita, G. M. (2013), Solar Physics, 288, 549. [https://ui.adsabs.harvard.edu/abs/2013SoPh..288..549G "Magnetography of Solar Flaring Loops with Microwave Imaging Spectropolarimetry"]

== VLA Flare List and Publications ==
See [http://www.ovsa.njit.edu/wiki/index.php/VLA_Data_Survey#List_of_Jansky_VLA_Solar_Observations this link] for a list of flare observations made by the [https://science.nrao.edu/facilities/vla/ Karl G. Jansky Very Large Array] (VLA). Below is a partial list of publications that utilize VLA solar data (see also [https://ui.adsabs.harvard.edu/public-libraries/ZwbjpLo9RS-viufWEoQ95Q this NASA/ADS Library]).
* [https://ui.adsabs.harvard.edu/abs/2022ApJ...940..137L/abstract Luo et al. (2022), ApJ, 940, 137] ''Multiple Regions of Nonthermal Quasiperiodic Pulsations during the Impulsive Phase of a Solar Flare''
* [https://ui.adsabs.harvard.edu/abs/2021ApJ...922..134B/abstract Battaglia et al. (2021), ApJ, 922, 134] ''Multiple Electron Acceleration Instances during a Series of Solar Microflares Observed Simultaneously at X-Rays and Microwaves''
* [https://ui.adsabs.harvard.edu/abs/2021ApJ...911....4L/abstract Luo et al. (2021), ApJ, 911, 4] ''Radio Spectral Imaging of an M8.4 Eruptive Solar Flare: Possible Evidence of a Termination Shock''
* [https://ui.adsabs.harvard.edu/abs/2021ApJ...910...40Z/abstract Zhang et al. (2021), ApJ, 910, 40] ''Multiwavelength Observations of the Formation and Eruption of a Complex Filament''
* [https://ui.adsabs.harvard.edu/abs/2020ApJ...904...94S/abstract Sharma et al. (2020), ApJ, 904, 94] ''Radio and X-Ray Observations of Short-lived Episodes of Electron Acceleration in a Solar Microflare''
* [https://ui.adsabs.harvard.edu/abs/2019ApJ...884...63C/abstract Chen et al. (2019), ApJ, 884, 63] ''Radio Spectroscopic Imaging of a Solar Flare Termination Shock: Split-band Feature as Evidence for Shock Compression''
* [https://ui.adsabs.harvard.edu/abs/2019ApJ...872...71Y/abstract Yu & Chen (2019), ApJ, 872, 71] ''Possible Detection of Subsecond-period Propagating Magnetohydrodynamics Waves in Post-reconnection Magnetic Loops during a Two-ribbon Solar Flare''
* [https://ui.adsabs.harvard.edu/abs/2018ApJ...866...62C/abstract Chen et al. (2018), ApJ, 866, 62] ''Magnetic Reconnection Null Points as the Origin of Semirelativistic Electron Beams in a Solar Jet
''
* [https://ui.adsabs.harvard.edu/abs/2017ApJ...848...77W/abstract Wang et al. (2016), ApJ, 848, 77] ''Dynamic Spectral Imaging of Decimetric Fiber Bursts in an Eruptive Solar Flare''
* [https://ui.adsabs.harvard.edu/abs/2015Sci...350.1238C/abstract Chen et al. (2015), Science, 350, 1238] ''Particle acceleration by a solar flare termination shock''
* [https://ui.adsabs.harvard.edu/abs/2014ApJ...794..149C/abstract Chen et al. (2014), ApJ, 794, 149] ''Direct Evidence of an Eruptive, Filament-hosting Magnetic Flux Rope Leading to a Fast Solar Coronal Mass Ejection''
* [https://ui.adsabs.harvard.edu/abs/2013ApJ...763L..21C/abstract Chen et al. (2013), ApJL, 763, 21] ''Tracing Electron Beams in the Sun's Corona with Radio Dynamic Imaging Spectroscopy''

==Radio Data from Around The Heliosphere==
* [http://ovsa.njit.edu//wiki/index.php/Radio_Data_from_Around_the_World#Radio_Data_Access '' Radio Data '']

=OVRO-LWA Solar-Dedicated Spectroscopic Imager=
The OVRO-LWA (Owens Valley Radio Observatory Long Wavelength Array) has recently been upgraded to include a solar-dedicated beam and two solar imaging modes (slow visibilities of 352 antennas with a 10-s cadence, and fast visibilities of 48 antennas with a 0.1-s cadence). The large collecting area and excellent calibration provide unprecedented high-sensitivity imaging of the quiet Sun and bursts. The array is currently in commissioning and observations are not yet continuous, but they are becoming more so. See the daily realtime data at http://ovsa.njit.edu/status.php for '''real-time display of the spectrogram and a selection of images''', both updated on a 1-min cadence.

==Solar-Dedicated Modes==
===Beamformer===
The beamformer uses the 256 core antennas to form a synthesized beam of more than 1 degree in size that tracks the Sun from sunrise to sunset. This permits a continuous record of the full-Stokes total flux (without spatial resolution) of the Sun (a dynamic spectrum) with 24 kHz frequency resolution (3072 frequencies from 15-90 MHz) and as low as 1 ms time resolution.

===Slow Visibility Imaging===
In this mode, the entire 352-element array is interferometrically correlated to provide visibilities for imaging at all 3072 frequencies at 10-s time resolution. This is ideal for imaging quiet Sun and slowly-varying emission such as coronal mass ejections and active region variability.

===Fast Visibility Imaging===
In this mode, a subset of 48 antennas (chosen to include mainly outer antennas to maintain good spatial resolution) is interferometrically correlated to provide visibilities for imaging at 768 frequencies (96 kHz frequency resolution) at 0.1-s time resolution. This is ideal for imaging rapidly varying emission such as type II and type III bursts as well as many other solar spectral fine structures.

==Inital Data Access==
In its current commissioning state, we try to run the beamformer and imaging pipeline every day in real-time since November 2023 (no latency for beamforming spectrograms and 5-10 min latency for images). Quicklook real-time spectrograms/images can be accessed from http://ovsa.njit.edu/status.php. To access data from previous days, use the following links (replace yyyymmdd with the date you desire):
* Quicklook beamformer total-power spectrograms: http://ovsa.njit.edu/lwa-data/1min_spectra/yyyymmdd/. Check this link for additional daily plots [[Daily OVRO-LWA Beamformer Data]].
* Quicklook multi-frequency movies at 1-min cadence: http://ovsa.njit.edu/lwa-data/1min_images/yyyymmdd/movie_yyyy-mm-dd.html

Note our pipeline processing development is still in the early phase. For example, absolute flux calibrations have not been done for the beamformer spectrograms. Also, artificial effects (including ionospheric refraction effects) are present in the images that cause distortions/shifts. We caution interested users only to consider them for quick-look purposes at this point. Please contact the EOVSA PIs (Dale Gary, Bin Chen) if you intend to use them for science.

==Operation Notes==
===Starting solar beamforming observations===
* Log into lwacalim10 (this is the only node that allows submissions)
* Activate the deployment conda environment
<pre> conda activate deployment </pre>
* Check what schedules are there
<pre>
lwaobserving show-schedule
</pre>
* Submit the schedule for the next 7 days (note that sdf files are written to /tmp/solar_<date>_<time>.sdf and will be owned by you).
<pre>
ipython
cd /home/dgary
import make_solar_sdf
make_solar_sdf.multiday_obs(ndays=7)
</pre>
* Calibrate the beam (if needed, using the same Python session)
<pre>
from mnc import control
con=control.Controller('/opt/devel/dgary/lwa_config_calim_std.yaml')
con.configure_xengine(['dr2'], calibratebeams=True)
</pre>

===Starting slow and fast visibility recorders ===
* Log into lwacalim10
* Check the recorder status by going to http://localhost:5006/LWA_dashboard
* Activate the environment and configure
<pre>
conda activate deployment
ipython
cd /home/pipeline/proj/lwa-shell/mnc_python/
from mnc import control
con=control.Controller('/opt/devel/dgary/lwa_config_calim_std.yaml')
</pre>
* Start the recorders
<pre>
con.start_dr(['drvs', 'drfv'])
</pre>
* Check the recorder status in command line
<pre>
con.status_dr()
</pre>

Owens Valley Solar Arrays

2024-09-26T22:43:32Z

Dgary: /* Starting solar beamforming observations */

[[File:Eovsa1.png|border|text-top|800px]]

<big>[http://ovsa.njit.edu/ EOVSA] (Expanded Owens Valley Solar Array) is a solar-dedicated radio interferometer operated by the New Jersey Institute of Technology and serving as a '''National Science Foundation Geospace Facility'''. [[File:NSF.jpg|70px]]
<pre>Operation of EOVSA is supported by the National Science Foundation under Grant No. AGS-2130832. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. </pre>
This wiki serves as the site for EOVSA documentation. </big>

[[File:OVRO-LWA1.png|border|text-top|800px]]

<big>OVRO-LWA (Owens Valley Radio Observatory Long Wavelength Array) is an all-sky imager that has a new solar-dedicated spectroscopic imaging mode. OVRO-LWA is a multi-institutional collaboration led by Caltech. NJIT Solar Radio Group is leading its solar-mode development and science. At the bottom of this page are new links for that facility. </big>

== EOVSA Flare List ==

* [https://ovsa.njit.edu/flarelist Query EOVSA Flare list]
* List of EOVSA flares in separate years: [[2024]], [[2023]], [[2022]], [[2021]], [[2020]], [[2019]], [[2017]]

== Using EOVSA Data ==
* <big>[[EOVSA Data products]]</big>: An introduction to standard EOVSA spectrogram and spectral image products with example scripts for reading and plotting.
* <big>[[EOVSA Data Policy]]</big>: Policy for using EOVSA data products.
* <big>Analysis Software</big>: These are for in-depth use of EOVSA data (from calibrated visibilities) and tools for quantitative analysis.
** [https://github.com/suncasa/suncasa SunCASA] A wrapper around [https://casa.nrao.edu/ CASA (the Common Astronomy Software Applications package)] for synthesis imaging and visualizing solar spectral imaging data. CASA is one of the leading software tool for "supporting the data post-processing needs of the next generation of radio astronomical telescopes such as ALMA and VLA", an international effort led by the [https://public.nrao.edu/ National Radio Astronomy Observatory]. The current version of CASA uses Python (2.7) interface. More information about CASA can be found on [https://casa.nrao.edu/ NRAO's CASA website ]. Note, CASA is available ONLY on UNIX-BASED PLATFORMS (and therefore, so is SunCASA).
** [https://github.com/Gelu-Nita/GSFIT GSFIT] A IDL-widget(GUI)-based spectral fitting package called gsfit, which provides a user-friendly display of EOVSA image cubes and an interface to fast fitting codes (via platform-dependent shared-object libraries).
** [https://github.com/suncasa/pygsfit pyGSFIT] A Python-widget(pyQT)-based spectral fitting package, which provides a user-friendly display of EOVSA image cubes, spatially resolved spectra, and an interface to scipy-based fitting codes.
** [[Spectrogram Software]]
** [[Mapping Software]]
* <big>Data Analysis Guides</big>
** <big>[[EOVSA Data Analysis Tutorial 2022]]</big> and <big>[https://colab.research.google.com/drive/19NQb6Emb9HvKX4QHq9ZYCP3RM6nT7sDL#scrollTo=cLdDVptBGG-X EOVSA Workspace]</big> at [https://sphere.boulder.swri.edu/ SPHERE 2022 Workshop]
** <big>[https://colab.research.google.com/drive/1lSLLxgOG6b8kgu9Sk6kSKvrViyubnXG6?usp=sharing#scrollTo=xbXyyLmCFCGL EOVSA Data Analysis Tutorial at RHESSI 19 Workshop]</big>
** <big>[[EOVSA Data Analysis Tutorial]]</big> at [http://rhessi18.umn.edu/ RHESSI XVIII Workshop]
** [[Self-Calibrating Flare Data]] Example script and guides for self-calibrating EOVSA flare data (to be completed)


**[[IDB flare pipeline]] Tutorial to run the flare pipeline for quicklook images



* <big>EOVSA Modeling Guide</big>
**[[GX Simulator]]

* Other helpful links
** [https://casaguides.nrao.edu CASA Guides]
** [http://www.lmsal.com/solarsoft/ SolarSoft IDL]
** [http://www.atnf.csiro.au/computing/software/miriad/userguide/userhtml.html Miriad Guides]
** [https://sites.google.com/site/fgscodes/ Fast Gyrosynchrotron Codes (Alexey Kuznetsov's website)]
** [[Basic GitHub Tutorial]]


* <big>[[Full Disk Simulations]]</big>
* <big>[[All-Day Synthesis Issues]]</big>
* <big>[[Analyzing Pre-2017 Data]]</big>
* <big>[[Fixing Pipeline Problems pre-2021-Feb-07]]</big>

== EOVSA Documentation ==

* <big>General</big>
** [[Downconversion and Frequency Tuning]]
** [[Dealing with Radio Frequency Interference]]
** [[Switching between 200 MHz and 300 MHz Correlator]]
** [[Observing in "Fast" Mode]]

* <big>Computer-Network</big>
** [[Computing Systems]]
** [[Network]]

* <big>Control System</big>
** [[27-m Antenna Commands]]
** [[Schedule Commands]]
** [[Control Commands]]
** [[Attenuation and Level Control]]

* <big>Hardware</big>
** [[Hardware Overview]]
** [[2.1-m Antennas]]
** [[27-m Antennas]]

* <big>System Software</big>
** [[Calibration Database]]
** [[Stateframe Database]]
** [[Database Maintenance]]
** [[Create CASA measurement sets]]

* <big>Calibration</big>
**[[Calibration Overview]]
**[[Pointing Calibration]]
**[[Total Power Calibration]]
**[[System Gain Calibration]]
**[[Antenna Position]] (Baseline Calibration)
**[[Reference Gain Calibration]]
**[[Daily Gain Calibration]]
**[[Delay Calibration]]
**[[Bandpass Calibration]]
**[[Polarization Calibration]]
**[[Calibrator Survey]]
**[[Practical Calibration Tutorial]]

* <big>[[Starburst]]</big>

== System Software ==

* LabVIEW software
* Python code [https://github.com/dgary50/eovsa Github repository]
* [[Python3 Code Installation]]

== EOVSA Observing Log ==
[[2016 November]]; [[2016 December| December]]

[[2017 January]]; [[2017 February | February]]; [[2017 March | March]]; [[2017 April | April]]; [[2017 May | May]]; [[2017 June | June]];
[[2017 July | July]]; [[2017 August | August]]; [[2017 September | September]]; [[2017 October | October]]; [[2017 November | November]]; [[2017 December | December]]

[[2018 January]]; [[2018 February | February]]; [[2018 March | March]]; [[2018 April | April]]; [[2018 May | May]]; [[2018 June | June]];
[[2018 July | July]]; [[2018 August | August]]; [[2018 September | September]]; [[2018 October | October]]; [[2018 November | November]]; [[2018 December | December]]

[[2019 January]]; [[2019 February | February]]; [[2019 March | March]]; [[2019 April | April]]; [[2019 May | May]]; [[2019 June | June]];
[[2019 July | July]]; [[2019 August | August]]; [[2019 September | September]]; [[2019 October | October]]; [[2019 November | November]]; [[2019 December | December]]

[[2020 January]]; [[2020 February | February]]; [[2020 March | March]]; [[2020 April | April]]; [[2020 May | May]]; [[2020 June | June]];
[[2020 July | July]]; [[2020 August | August]]; [[2020 September | September]]; [[2020 October | October]]; [[2020 November | November]]; [[2020 December | December]]

[[2021 January]]; [[2021 February | February]]; [[2021 March | March]]; [[2021 April | April]]; [[2021 May | May]]; [[2021 June | June]];
[[2021 July | July]]; [[2021 August | August]]; [[2021 September | September]]; [[2021 October | October]]; [[2021 November | November]]; [[2021 December | December]]

[[2022 SQL Outage]]

[[2023 January]]; [[2023 February | February]]; [[2023 March | March]]; [[2023 April | April]]; [[2023 May | May]]; [[2023 June | June]];
[[2023 July | July]]; [[2023 August | August]]; [[2023 September | September]]; [[2023 October | October]]; [[2023 November | November]]; [[2023 December | December]]

[[2024 January]]; [[2024 February | February]]; [[2024 March | March]];[[2024 April | April]];[[2024 May |May]]; [[2024 June | June]]; [[2024 July | July]]; [[2024 August | August]];
[[2024 September | September]]

== SoD Observing Logs ==
* See [https://docs.google.com/document/d/1_iGnMRRrvb85Z0vT8-LzgQmCOKDSATEuQ0vTsn2C-dc/edit?usp=sharing SoD Routines] for detailed instructions for Scientist-on-Duty routines.
* 2024 [https://docs.google.com/document/d/1QDWw5y4HpcE7CSpzXwftMqQT4FDgNJj-6fRrgWrqdug/edit?usp=sharing May (and before that)], [https://docs.google.com/document/d/1Rh2gYBV2E454xVYEv8jx5IXKd1N2Z05ns4dhI2XCE08/edit?usp=sharing June], [https://docs.google.com/document/d/1beUpp6rgwjqSxKbuHzXIR9hhPrGyi0j-SjtEIeav9Vg/edit?usp=sharing July], [https://docs.google.com/document/d/1pSzUXW5gd-4cZAR-gglTUVM_J2UHMa4wYJ2AzD4cdEo/edit?usp=sharing August], [https://docs.google.com/document/d/18pArAP0kRDhXHbty_y3TtrygmWkC2oLn-UD7njIpRIo/edit?usp=sharing September], October, November, December

== Tohbans ==

[[Trouble Shooting Guide]]

[[Tohban Records]]

[[Owen's Notes]]

[[Caius' Notes]]

[[Tohban EOVSA Imaging Tutorial A-Z]]

[[Tohban OVRO-LWA Imaging Tutorial]]

[[Tohban Guide to Self Calibration and Imaging for EOVSA]]

[[Guide to Upgrade SolarSoft(SSW)]]

== EOVSA Publications ==
Here is a (partial) list of publications that utilize EOVSA data. See also the collection of EOVSA publications at [https://ui.adsabs.harvard.edu/public-libraries/eQ7HfPkySqydu-B8BCt6QQ this NASA/ADS Library].
; 2024
: Collier, H., Hayes, L. A., Yu, S., Battaglia, A. F., Ashfield, W., Polito, V., Harra, L. K., & Krucker, S. (2024), arXiv e-prints, arXiv:2402.10546. [https://ui.adsabs.harvard.edu/abs/2024arXiv240210546C “Localising pulsations in the hard X-ray and microwave emission of an X-class flare”]
: Saqri, J., Veronig, A. M., Battaglia, A. F., Dickson, E. C. M., Gary, D. E., & Krucker, S. (2024), Astronomy and Astrophysics, 683, A41. [https://ui.adsabs.harvard.edu/abs/2024A&A...683A..41S "Efficiency of solar microflares in accelerating electrons when rooted in a sunspot"]
; 2023
: Tan, B., Yan, Y., Huang, J., Zhang, Y., Tan, C., & Zhu, X. (2023), Advances in Space Research, 72, 5563. [https://ui.adsabs.harvard.edu/abs/2023AdSpR..72.5563T "The physics of solar spectral imaging observations in dm-cm wavelengths and the application on space weather"]

: Li, D., Li, Z., Shi, F., Su, Y., Chen, W., Yu, F., Li, C., Qiu, Y., Huang, Y., & Ning, Z. (2023), Astronomy and Astrophysics, 680, L15. [https://ui.adsabs.harvard.edu/abs/2023A&A...680L..15L "Observational signature of continuously operating drivers of decayless kink oscillation"]

: Wang, M., Chen, B., Yu, S., Gary, D. E., Lee, J., Wang, H., & Cohen, C. (2023), The Astrophysical Journal, 954, 32. [https://ui.adsabs.harvard.edu/abs/2023ApJ...954...32W "The Solar Origin of an In Situ Type III Radio Burst Event"]

: Gary, D. E. (2023), Annual Review of Astronomy and Astrophysics, 61, 427. [https://ui.adsabs.harvard.edu/abs/2023ARA&A..61..427G "New Insights from Imaging Spectroscopy of Solar Radio Emission"]

: Nita, G. M., Fleishman, G. D., Kuznetsov, A. A., Anfinogentov, S. A., Stupishin, A. G., Kontar, E. P., Schonfeld, S. J., Klimchuk, J. A., & Gary, D. E. (2023), The Astrophysical Journal Supplement Series, 267, 6. [https://ui.adsabs.harvard.edu/abs/2023ApJS..267....6N "Data-constrained Solar Modeling with GX Simulator"]

: Song, D.-C., Tian, J., Li, Y., Ding, M. D., Su, Y., Yu, S., Hong, J., Qiu, Y., Rao, S., Liu, X., Li, Q., Chen, X., Li, C., & Fang, C. (2023), The Astrophysical Journal, 952, L6. [https://ui.adsabs.harvard.edu/abs/2023ApJ...952L...6S "Spectral Observations and Modeling of a Solar White-light Flare Observed by CHASE"]

: Mondal, S., Chen, B., & Yu, S. (2023), The Astrophysical Journal, 949, 56. [https://ui.adsabs.harvard.edu/abs/2023ApJ...949...56M "Multifrequency Microwave Imaging of Weak Transients from the Quiet Solar Corona"]

: Kontar, E. P., Emslie, A. G., Motorina, G. G., & Dennis, B. R. (2023), The Astrophysical Journal, 947, L13. [https://ui.adsabs.harvard.edu/abs/2023ApJ...947L..13K "The Efficiency of Electron Acceleration during the Impulsive Phase of a Solar Flare"]

: Saqri, J., Veronig, A. M., Dickson, E. C. M., Podladchikova, T., Warmuth, A., Xiao, H., Gary, D. E., Battaglia, A. F., & Krucker, S. (2023), Astronomy and Astrophysics, 672, A23. [https://ui.adsabs.harvard.edu/abs/2023A&A...672A..23S "Multi-point study of the energy release and impulsive CME dynamics in an eruptive C7 flare"]
; 2022

: Kou, Y., Cheng, X., Wang, Y., Yu, S., Chen, B., Kontar, E. P., & Ding, M. (2022), Nature Communications, 13, 7680. [https://ui.adsabs.harvard.edu/abs/2022NatCo..13.7680K "Microwave imaging of quasi-periodic pulsations at flare current sheet"]

: Chertok, I. M. (2022), Monthly Notices of the Royal Astronomical Society, 517, 2709. [https://ui.adsabs.harvard.edu/abs/2022MNRAS.517.2709C "On some features of the solar proton event on 2021 October 28 - GLE73"]

: Lörinčík, J., Polito, V., De Pontieu, B., Yu, S., & Freij, N. (2022), Frontiers in Astronomy and Space Sciences, 9, 334. [https://ui.adsabs.harvard.edu/abs/2022FrASS...940945L "Rapid variations of Si IV spectra in a flare observed by interface region imaging spectrograph at a sub-second cadence"]

: Klein, K.-L., Musset, S., Vilmer, N., Briand, C., Krucker, S., Francesco Battaglia, A., Dresing, N., Palmroos, C., & Gary, D. E. (2022), Astronomy and Astrophysics, 663, A173. [https://ui.adsabs.harvard.edu/abs/2022A&A...663A.173K "The relativistic solar particle event on 28 October 2021: Evidence of particle acceleration within and escape from the solar corona"]

: Fleishman, G. D., Nita, G. M., Chen, B., Yu, S., & Gary, D. E. (2022), Nature, 606, 674. [https://ui.adsabs.harvard.edu/abs/2022Natur.606..674F "Solar flare accelerates nearly all electrons in a large coronal volume"]

: Li, X., Guo, F., Chen, B., Shen, C., & Glesener, L. (2022), The Astrophysical Journal, 932, 92. [https://ui.adsabs.harvard.edu/abs/2022ApJ...932...92L "Modeling Electron Acceleration and Transport in the Early Impulsive Phase of the 2017 September 10th Solar Flare"]

: Zhang, J., Chen, B., Yu, S., Tian, H., Wei, Y., Chen, H., Tan, G., Luo, Y., & Chen, X. (2022), The Astrophysical Journal, 932, 53. [https://ui.adsabs.harvard.edu/abs/2022ApJ...932...53Z "Implications for Additional Plasma Heating Driving the Extreme-ultraviolet Late Phase of a Solar Flare with Microwave Imaging Spectroscopy"]

: Liu, N., Jing, J., Xu, Y., & Wang, H. (2022), The Astrophysical Journal, 930, 154. [https://ui.adsabs.harvard.edu/abs/2022ApJ...930..154L "Multi-instrument Comparative Study of Temperature, Number Density, and Emission Measure during the Precursor Phase of a Solar Flare"]

: López, F. M., Giménez de Castro, C. G., Mandrini, C. H., Simões, P. J. A., Cristiani, G. D., Gary, D. E., Francile, C., & Démoulin, P. (2022), Astronomy and Astrophysics, 657, A51. [https://ui.adsabs.harvard.edu/abs/2022A&A...657A..51L "A solar flare driven by thermal conduction observed in mid-infrared"]

: Unverferth, J., & Longcope, D. (2021), The Astrophysical Journal, 923, 248. [https://ui.adsabs.harvard.edu/abs/2021ApJ...923..248U "Examining Flux Tube Interactions as a Cause of Sub-alfvénic Outflow"]
;2021

: Wei, Y., Chen, B., Yu, S., Wang, H., Jing, J., & Gary, D. E. (2021), The Astrophysical Journal, 923, 213. [https://ui.adsabs.harvard.edu/abs/2021ApJ...923..213W "Coronal Magnetic Field Measurements along a Partially Erupting Filament in a Solar Flare"]

: Jing, J., Inoue, S., Lee, J., Li, Q., Nita, G. M., Xu, Y., Liu, C., Gary, D. E., & Wang, H. (2021), The Astrophysical Journal, 922, 108. [https://ui.adsabs.harvard.edu/abs/2021ApJ...922..108J "Understanding the Initiation of the M2.4 Flare on 2017 July 14"]

: Battaglia, A. F., Saqri, J., Massa, P., Perracchione, E., Dickson, E. C. M., Xiao, H., Veronig, A. M., Warmuth, A., Battaglia, M., Hurford, G. J., Meuris, A., Limousin, O., Etesi, L., Maloney, S. A., Schwartz, R. A., Kuhar, M., Schuller, F., Senthamizh Pavai, V., Musset, S., Ryan, D. F., Kleint, L., Piana, M., Massone, A. M., Benvenuto, F., Sylwester, J., Litwicka, M., Stȩślicki, M., Mrozek, T., Vilmer, N., Fárník, F., Kašparová, J., Mann, G., Gallagher, P. T., Dennis, B. R., Csillaghy, A., Benz, A. O., & Krucker, S. (2021), Astronomy and Astrophysics, 656, A4. [https://ui.adsabs.harvard.edu/abs/2021A&A...656A...4B "STIX X-ray microflare observations during the Solar Orbiter commissioning phase"]

: Shaik, S. B., & Gary, D. E. (2021), The Astrophysical Journal, 919, 44. [https://ui.adsabs.harvard.edu/abs/2021ApJ...919...44S "Implications of Flat Optically Thick Microwave Spectra in Solar Flares for Source Size and Morphology"]

: Kocharov, L., Omodei, N., Mishev, A., Pesce-Rollins, M., Longo, F., Yu, S., Gary, D. E., Vainio, R., & Usoskin, I. (2021), The Astrophysical Journal, 915, 12. [https://ui.adsabs.harvard.edu/abs/2021ApJ...915...12K "Multiple Sources of Solar High-energy Protons"]

: Chen, B., Battaglia, M., Krucker, S., Reeves, K. K., & Glesener, L. (2021), The Astrophysical Journal, 908, L55. [https://ui.adsabs.harvard.edu/abs/2021ApJ...908L..55C "Energetic Electron Distribution of the Coronal Acceleration Region: First Results from Joint Microwave and Hard X-Ray Imaging Spectroscopy"]

: Chhabra, S., Gary, D. E., Hallinan, G., Anderson, M. M., Chen, B., Greenhill, L. J., & Price, D. C. (2021), The Astrophysical Journal, 906, 132. [https://ui.adsabs.harvard.edu/abs/2021ApJ...906..132C "Imaging Spectroscopy of CME-associated Solar Radio Bursts using OVRO-LWA"]
;2020 and earlier

: Reeves, K. K., Polito, V., Chen, B., Galan, G., Yu, S., Liu, W., & Li, G. (2020), The Astrophysical Journal, 905, 165. [https://ui.adsabs.harvard.edu/abs/2020ApJ...905..165R "Hot Plasma Flows and Oscillations in the Loop-top Region During the 2017 September 10 X8.2 Solar Flare"]

: Nindos, A. (2020), Frontiers in Astronomy and Space Sciences, 7, 57. [https://ui.adsabs.harvard.edu/abs/2020FrASS...7...57N "Incoherent Solar Radio Emission"]

: Yu, S., Chen, B., Reeves, K. K., Gary, D. E., Musset, S., Fleishman, G. D., Nita, G. M., & Glesener, L. (2020), The Astrophysical Journal, 900, 17. [https://ui.adsabs.harvard.edu/abs/2020ApJ...900...17Y "Magnetic Reconnection during the Post-impulsive Phase of a Long-duration Solar Flare: Bidirectional Outflows as a Cause of Microwave and X-Ray Bursts"]

: Chen, B., Yu, S., Reeves, K. K., & Gary, D. E. (2020), The Astrophysical Journal, 895, L50. [https://ui.adsabs.harvard.edu/abs/2020ApJ...895L..50C "Microwave Spectral Imaging of an Erupting Magnetic Flux Rope: Implications for the Standard Solar Flare Model in Three Dimensions"]

: Kuroda, N., Fleishman, G. D., Gary, D. E., Nita, G. M., Chen, B., & Yu, S. (2020), Frontiers in Astronomy and Space Sciences, 7, 22. [https://ui.adsabs.harvard.edu/abs/2020FrASS...7...22K "Evolution of Flare-accelerated Electrons Quantified by Spatially Resolved Analysis"]

: Glesener, L., Krucker, S., Duncan, J., Hannah, I. G., Grefenstette, B. W., Chen, B., Smith, D. M., White, S. M., & Hudson, H. (2020), The Astrophysical Journal, 891, L34. [https://ui.adsabs.harvard.edu/abs/2020ApJ...891L..34G "Accelerated Electrons Observed Down to <7 keV in a NuSTAR Solar Microflare"]

: Karlický, M., Chen, B., Gary, D. E., Kašparová, J., & Rybák, J. (2020), The Astrophysical Journal, 889, 72. [https://ui.adsabs.harvard.edu/abs/2020ApJ...889...72K "Drifting Pulsation Structure at the Very Beginning of the 2017 September 10 Limb Flare"]

: Fleishman, G. D., Gary, D. E., Chen, B., Kuroda, N., Yu, S., & Nita, G. M. (2020), Science, 367, 278. [https://ui.adsabs.harvard.edu/abs/2020Sci...367..278F "Decay of the coronal magnetic field can release sufficient energy to power a solar flare"]

: Chen, B., Shen, C., Gary, D. E., Reeves, K. K., Fleishman, G. D., Yu, S., Guo, F., Krucker, S., Lin, J., Nita, G. M., & Kong, X. (2020), Nature Astronomy, 4, 1140. [https://ui.adsabs.harvard.edu/abs/2020NatAs...4.1140C "Measurement of magnetic field and relativistic electrons along a solar flare current sheet"]

: Lee, J. (2018), Journal of Astronomy and Space Sciences, 35, 211. [https://ui.adsabs.harvard.edu/abs/2018JASS...35..211L "Analysis of Solar Microwave Burst Spectrum, I. Nonuniform Magnetic Field"]

: Gary, D. E., Bastian, T. S., Chen, B., Fleishman, G. D., & Glesener, L. (2018), Science with a Next Generation Very Large Array, 517, 99. [https://ui.adsabs.harvard.edu/abs/2018ASPC..517...99G "Radio Observations of Solar Flares"]

: Polito, V., Dudík, J., Kašparová, J., Dzifčáková, E., Reeves, K. K., Testa, P., & Chen, B. (2018), The Astrophysical Journal, 864, 63. [https://ui.adsabs.harvard.edu/abs/2018ApJ...864...63P "Broad Non-Gaussian Fe XXIV Line Profiles in the Impulsive Phase of the 2017 September 10 X8.3-class Flare Observed by Hinode/EIS"]

: Gary, D. E., Chen, B., Dennis, B. R., Fleishman, G. D., Hurford, G. J., Krucker, S., McTiernan, J. M., Nita, G. M., Shih, A. Y., White, S. M., & Yu, S. (2018), The Astrophysical Journal, 863, 83. [https://ui.adsabs.harvard.edu/abs/2018ApJ...863...83G "Microwave and Hard X-Ray Observations of the 2017 September 10 Solar Limb Flare"]

: Fleishman, G. D., Nita, G. M., Kuroda, N., Jia, S., Tong, K., Wen, R. R., & Zhizhuo, Z. (2018), The Astrophysical Journal, 859, 17. [https://ui.adsabs.harvard.edu/abs/2018ApJ...859...17F "Revealing the Evolution of Non-thermal Electrons in Solar Flares Using 3D Modeling"]

: Kuroda, N., Gary, D. E., Wang, H., Fleishman, G. D., Nita, G. M., & Jing, J. (2018), The Astrophysical Journal, 852, 32. [https://ui.adsabs.harvard.edu/abs/2018ApJ...852...32K "Three-dimensional Forward-fit Modeling of the Hard X-Ray and Microwave Emissions of the 2015 June 22 M6.5 Flare"]

: Wang, H., Liu, C., Ahn, K., Xu, Y., Jing, J., Deng, N., Huang, N., Liu, R., Kusano, K., Fleishman, G. D., Gary, D. E., & Cao, W. (2017), Nature Astronomy, 1, 0085. [https://ui.adsabs.harvard.edu/abs/2017NatAs...1E..85W "High-resolution observations of flare precursors in the low solar atmosphere"]

: Nita, G. M., Hickish, J., MacMahon, D., & Gary, D. E. (2016), Journal of Astronomical Instrumentation, 5, 1641009-7366. [https://ui.adsabs.harvard.edu/abs/2016JAI.....541009N "EOVSA Implementation of a Spectral Kurtosis Correlator for Transient Detection and Classification"]

: Nita, G. M., & Gary, D. E. (2016), Journal of Geophysical Research (Space Physics), 121, 7353. [https://ui.adsabs.harvard.edu/abs/2016JGRA..121.7353N "Measurement of duration and signal-to-noise ratio of astronomical transients using a Spectral Kurtosis spectrometer"]

: Wang, Z., Gary, D. E., Fleishman, G. D., & White, S. M. (2015), The Astrophysical Journal, 805, 93. [https://ui.adsabs.harvard.edu/abs/2015ApJ...805...93W "Coronal Magnetography of a Simulated Solar Active Region from Microwave Imaging Spectropolarimetry"]

: Gary, D. E., Fleishman, G. D., & Nita, G. M. (2013), Solar Physics, 288, 549. [https://ui.adsabs.harvard.edu/abs/2013SoPh..288..549G "Magnetography of Solar Flaring Loops with Microwave Imaging Spectropolarimetry"]

== VLA Flare List and Publications ==
See [http://www.ovsa.njit.edu/wiki/index.php/VLA_Data_Survey#List_of_Jansky_VLA_Solar_Observations this link] for a list of flare observations made by the [https://science.nrao.edu/facilities/vla/ Karl G. Jansky Very Large Array] (VLA). Below is a partial list of publications that utilize VLA solar data (see also [https://ui.adsabs.harvard.edu/public-libraries/ZwbjpLo9RS-viufWEoQ95Q this NASA/ADS Library]).
* [https://ui.adsabs.harvard.edu/abs/2022ApJ...940..137L/abstract Luo et al. (2022), ApJ, 940, 137] ''Multiple Regions of Nonthermal Quasiperiodic Pulsations during the Impulsive Phase of a Solar Flare''
* [https://ui.adsabs.harvard.edu/abs/2021ApJ...922..134B/abstract Battaglia et al. (2021), ApJ, 922, 134] ''Multiple Electron Acceleration Instances during a Series of Solar Microflares Observed Simultaneously at X-Rays and Microwaves''
* [https://ui.adsabs.harvard.edu/abs/2021ApJ...911....4L/abstract Luo et al. (2021), ApJ, 911, 4] ''Radio Spectral Imaging of an M8.4 Eruptive Solar Flare: Possible Evidence of a Termination Shock''
* [https://ui.adsabs.harvard.edu/abs/2021ApJ...910...40Z/abstract Zhang et al. (2021), ApJ, 910, 40] ''Multiwavelength Observations of the Formation and Eruption of a Complex Filament''
* [https://ui.adsabs.harvard.edu/abs/2020ApJ...904...94S/abstract Sharma et al. (2020), ApJ, 904, 94] ''Radio and X-Ray Observations of Short-lived Episodes of Electron Acceleration in a Solar Microflare''
* [https://ui.adsabs.harvard.edu/abs/2019ApJ...884...63C/abstract Chen et al. (2019), ApJ, 884, 63] ''Radio Spectroscopic Imaging of a Solar Flare Termination Shock: Split-band Feature as Evidence for Shock Compression''
* [https://ui.adsabs.harvard.edu/abs/2019ApJ...872...71Y/abstract Yu & Chen (2019), ApJ, 872, 71] ''Possible Detection of Subsecond-period Propagating Magnetohydrodynamics Waves in Post-reconnection Magnetic Loops during a Two-ribbon Solar Flare''
* [https://ui.adsabs.harvard.edu/abs/2018ApJ...866...62C/abstract Chen et al. (2018), ApJ, 866, 62] ''Magnetic Reconnection Null Points as the Origin of Semirelativistic Electron Beams in a Solar Jet
''
* [https://ui.adsabs.harvard.edu/abs/2017ApJ...848...77W/abstract Wang et al. (2016), ApJ, 848, 77] ''Dynamic Spectral Imaging of Decimetric Fiber Bursts in an Eruptive Solar Flare''
* [https://ui.adsabs.harvard.edu/abs/2015Sci...350.1238C/abstract Chen et al. (2015), Science, 350, 1238] ''Particle acceleration by a solar flare termination shock''
* [https://ui.adsabs.harvard.edu/abs/2014ApJ...794..149C/abstract Chen et al. (2014), ApJ, 794, 149] ''Direct Evidence of an Eruptive, Filament-hosting Magnetic Flux Rope Leading to a Fast Solar Coronal Mass Ejection''
* [https://ui.adsabs.harvard.edu/abs/2013ApJ...763L..21C/abstract Chen et al. (2013), ApJL, 763, 21] ''Tracing Electron Beams in the Sun's Corona with Radio Dynamic Imaging Spectroscopy''

==Radio Data from Around The Heliosphere==
* [http://ovsa.njit.edu//wiki/index.php/Radio_Data_from_Around_the_World#Radio_Data_Access '' Radio Data '']

=OVRO-LWA Solar-Dedicated Spectroscopic Imager=
The OVRO-LWA (Owens Valley Radio Observatory Long Wavelength Array) has recently been upgraded to include a solar-dedicated beam and two solar imaging modes (slow visibilities of 352 antennas with a 10-s cadence, and fast visibilities of 48 antennas with a 0.1-s cadence). The large collecting area and excellent calibration provide unprecedented high-sensitivity imaging of the quiet Sun and bursts. The array is currently in commissioning and observations are not yet continuous, but they are becoming more so. See the daily realtime data at http://ovsa.njit.edu/status.php for '''real-time display of the spectrogram and a selection of images''', both updated on a 1-min cadence.

==Solar-Dedicated Modes==
===Beamformer===
The beamformer uses the 256 core antennas to form a synthesized beam of more than 1 degree in size that tracks the Sun from sunrise to sunset. This permits a continuous record of the full-Stokes total flux (without spatial resolution) of the Sun (a dynamic spectrum) with 24 kHz frequency resolution (3072 frequencies from 15-90 MHz) and as low as 1 ms time resolution.

===Slow Visibility Imaging===
In this mode, the entire 352-element array is interferometrically correlated to provide visibilities for imaging at all 3072 frequencies at 10-s time resolution. This is ideal for imaging quiet Sun and slowly-varying emission such as coronal mass ejections and active region variability.

===Fast Visibility Imaging===
In this mode, a subset of 48 antennas (chosen to include mainly outer antennas to maintain good spatial resolution) is interferometrically correlated to provide visibilities for imaging at 768 frequencies (96 kHz frequency resolution) at 0.1-s time resolution. This is ideal for imaging rapidly varying emission such as type II and type III bursts as well as many other solar spectral fine structures.

==Inital Data Access==
In its current commissioning state, we try to run the beamformer and imaging pipeline every day in real-time since November 2023 (no latency for beamforming spectrograms and 5-10 min latency for images). Quicklook real-time spectrograms/images can be accessed from http://ovsa.njit.edu/status.php. To access data from previous days, use the following links (replace yyyymmdd with the date you desire):
* Quicklook beamformer total-power spectrograms: http://ovsa.njit.edu/lwa-data/1min_spectra/yyyymmdd/. Check this link for additional daily plots [[Daily OVRO-LWA Beamformer Data]].
* Quicklook multi-frequency movies at 1-min cadence: http://ovsa.njit.edu/lwa-data/1min_images/yyyymmdd/movie_yyyy-mm-dd.html

Note our pipeline processing development is still in the early phase. For example, absolute flux calibrations have not been done for the beamformer spectrograms. Also, artificial effects (including ionospheric refraction effects) are present in the images that cause distortions/shifts. We caution interested users only to consider them for quick-look purposes at this point. Please contact the EOVSA PIs (Dale Gary, Bin Chen) if you intend to use them for science.

==Operation Notes==
===Starting solar beamforming observations===
* Log into lwacalim10 (this is the only node that allows submissions)
* Activate the deployment conda environment
<pre> conda activate deployment </pre>
* Check what schedules are there
<pre>
lwaobserving show-schedule
</pre>
* Submit the schedule for the next 7 days (note that sdf files are written to /tmp/solar_<date>_<time>.sdf and will be owned by you).
<pre>
cd /home/dgary
import make_solar_sdf
make_solar_sdf.multiday_obs(ndays=7)
</pre>
* Calibrate the beam
<pre>
cd /home/pipeline/proj/lwa-shell/mnc_python/
ipython
from mnc import control
con=control.Controller('/opt/devel/dgary/lwa_config_calim_std.yaml')
con.configure_xengine(['dr2'], calibratebeams=True)
</pre>

Downconversion and Frequency Tuning

2024-09-24T23:26:40Z

Dgary:

== Background ==
EOVSA has three consecutive frequency-conversion operations required to tune and isolate a clean 500 MHz IF band from the 1-18 GHz RF band. The first is a tunable upconversion to a 20-20.5 GHz band, which is filtered but with a rather gentle roll-off due to the high center frequency. The second is a fixed-frequency downconversion of the 20-20.5 GHz band centered on a sharply filtered IF bandpass from 600-1200 MHz. The third downconversion is that due to the digitizer, whose nominal clock is 1200 MHz, although for practical reasons during the prototype phase we are operating the digitizer at a sub-optimal 800 MHz clock speed.
This document describes these frequency conversions and the resultant ordering of frequency channels in the digitized data, both for the production unit with a 1200 MHz digitizer clock, and for this interim period with an 800 MHz clock. We demonstrate that the system corresponds to our expectations by introducing a frequency-swept CW signal into the IF path and observing its effects. We also discuss the linearity of the system, which probably belongs in a separate memo.

== Tuning and First Frequency-Conversion ==

Figure 1 shows the basic tuning operation for four different IF bands. Each tuning inverts the 1-18 GHz RF by mirroring it around the LO frequency. To tune to each of the 500 MHz between 1-18 GHz, 34 tunings are required ranging from 21.5 GHz to 38 GHz. The RF frequency at the low end of the 500 MHz band is related by the LO frequency by <math>\nu_{RF}=\nu_{LO}-</math>20.5GHz. In the figure, the RF frequency scale is shown in black, and the IF frequency scale (after the conversion) is shown in blue. As the LO frequency changes, the mirrored RF band slides to the right with twice the step of the LO frequency change, while the fixed 20-20.5 GHz filter slides to the right with the same step as the LO. Thus, the mirrored RF slides past the filter window at the same rate as the LO frequency change. Note that the RF frequencies are inverted due to the mirroring.

[[File:image1.png|thumb|center|800px|Figure1:Schematic representation of frequency tuning for EOVSA, showing tuning to four of the 34 RF bands. From top to bottom they are: 1.5-2 GHz, 3.5-4 GHz, 7.5-8 GHz, and 17.5-18 GHz.]]

== Second Frequency-Conversion ==

In order to digitize the signal, the high-frequency IF must be converted to a lower frequency. To accomplish this, the EOVSA system mixes the fixed 20-20.5 GHz signal with a fixed 21.15 GHz second LO as shown in Figure 2, whose format is similar to that of Figure 1. The rather gentle roll-off of the 20-20.5 GHz filter is indicated by the sloping sides of the bandpass. Again, the original frequency scale is shown in black, and the mirrored copy of the bandpass is shown in blue, labeled with its lower IF frequency scale in MHz, also in blue. This IF bandpass shape is then filtered with a sharply defined IF filter from 600-1200 MHz (outer dashed lines marked as Digitized Bandpass). This second mirroring of the band causes the previously inverted RF frequencies to again have a direct ordering.

[[File:image2.png|thumb|center|800px|Figure 2: Schematic representation of the second EOVSA downconversion, where the high-frequency IF band on the left, whose frequency scale is marked in black (in GHz), is mirrored and converted to the IF band on the right, marked in blue (in MHz). The effect of the low-frequency (650-1150 MHz passband) IF filter is shown on the right in black.]]

== Digitization and the Third Frequency-Conversion ==

This second IF band is now at a sufficiently low frequency for digitization. For the final production system, EOVSA’s correlator will digitize the signal using a 1200 MHz clock. This action will mirror the IF a third time, as shown in Figure 3. The clock frequency is 50 MHz above the desired band, and the passband of the filter is 100 MHz narrower than the 600 MHz nyquist bandwidth of the clock, so that the skirt of the filter roll-off, which is aliased back into the passband, is reduced by 63 dB below the desired signal. The 600 MHz digitized passband is shown in green, but the target passband is the narrower 500 MHz band indicated between 50 and 550 MHz. Because the correlator F-engine produces 4096 channels over 600 MHz, the actual desired data will be found in channels 341-3755. For the production system, then, this third mirroring of the RF will result in an inverted order of frequency channels, but with the fortunate advantage that this inversion never changes--it does not depend on the RF band to which the system has been tuned.

[[File:image3.png|thumb|center|800px|Figure 3: Schematic representation of the third EOVSA downconversion by the digitizer. The filtered second IF band on the left, whose frequency scale is marked in black (in MHz), is mirrored and converted to the IF band on the right, marked in blue (in MHz). The 600 MHz-wide digitized bandpass is shown in green, while the narrower 500 MHz target bandpass is shown by the inner dashed lines on the right.]]

Unfortunately, it has been necessary to temporarily restrict the digitizer clock during the prototype phase to 800 MHz (an FPGA clock speed of 200 MHz), which provides a nyquist bandwidths of only 400 MHz. Figure 4 shows the impact of this non-ideal clock speed on the digitized band.

[[File:image4.png|thumb|center|800px|Figure 4: Schematic representation of the third EOVSA downconversion by the digitizer, when the digitizer clock is at the non-ideal frequency of 800 MHz. The second IF band is shown in black (in MHz), while the mirrored IF band partially overlaps and extends to the left, marked in blue. The green block indicates the downconverted, digitized bandpass, whose scale is shown in blue (in MHz). The part of the band contaminated with overlapping is shown as the darker green hatched area.]]

Clearly the resulting data are compromised, because the lower half of the 400 MHz bandwidth is contaminated due to the 200 MHz range from 600-800 MHz being folded onto the 800-1000 MHz band. Only the 1000-1200 MHz range of the filtered second IF will be clean, and will be downconverted to the 200-400 MHz IF range. Note also that the 800-1200 MHz range of the filtered second IF will have direct RF ordering, while the mirrored 600-800 MHz range will have inverted ordering.



In February 2019, new IF filters were installed in the DCMs, from 825-1150 MHz, providing a clear range 325 MHz with no overlap. By tuning at harmonics of 325 MHz, we cover the entire 1-18 GHz range without gaps. 17 GHz / 0.325 = 52 is the number of tunings required, but 2 bands are skipped (bands 3 and 4) due to the notch filter that blocks the cell tower interference, leaving 50 slots. That exactly matches the number of tunings available in 1 s (at 20 ms per tuning).

Tohban EOVSA Imaging Tutorial A-Z

2024-05-17T16:04:10Z

Dgary: /* Calibration on your own computer */

This tutorial describes the step-by-step procedure to download EOVSA IDB data, obtain and calibrate the measurement sets (.ms), and, transfer them to the inti server for self-calibration and further analysis.

'''Pre-requisites:''' Accounts on Pipeline and Inti or Baozi servers.

== Calibration on your own computer ==
[[File: Quick_Start.png|thumb|600px|Once you have downloaded an IDB file and installed both suncasa and eovsapy on your own computer, you can create a calibrated CASA measurement set with these minimal commands at the ipython command line:

<pre>
from suncasa.suncasatasks import calibeovsa
from suncasa.suncasatasks import importeovsa
try:
# Required in modular casa, but fails in stand-alone casa
from casatasks import split
except:
pass
idbfile = <IDB filename> # The path and filename of the IDB file
msfiles = importeovsa(idbfiles=idbfile)
vis, = calibeovsa(msfiles, caltype=['refpha','phacal'])
outvis = vis.replace('.ms','_cal.ms')
split(vis=vis, outputvis=outvis, correlation='XX')
</pre>

If all goes well, this will result in a fully-calibrated visibility dataset with the string "_cal.ms" appended to the IDB filename, located in the same place as the original IDB file. You can then start with Step 4 below, for self-calibration.
]]
It is now possible to do the entire calibration procedure from anywhere by copying to your local computer one or more raw interim database (IDB) files in Miriad format and calibrating them from a cloud database. Here are the steps. First, find the IDB file(s) of interest. The IDB files are all available online at the following links:

* '''2017 Apr - present - 7 days: https://research.ssl.berkeley.edu/data/eovsa/'''
* '''2024 Jan - present: http://ovsa.njit.edu/fits/IDB/'''

Once you have the file(s) identified for the date and time of interest, copy them to your local computer. One way to do that is with the wget command:
<pre> wget -r --no-parent -nH --cut-dirs=3 -e robots="off" -R "index.html*" <URL> </pre>
where <URL> is the path to the file(s). For example, to get the data for the flare at 2022 Nov 18 22:04 UT [http://www.ovsa.njit.edu/wiki/images/8/8c/EOVSA_20221118_C1flare.png] the URL would be http://ovsa.njit.edu/IDB2/20221118/IDB20221118215521/. Warning, these IDB "files" are actually directories, so include the trailing / in the URL or else you will transfer the entire day's data (many GB of data!). An easy way to get the URL is simply to right-click on the web link for the file and "copy link address."

=== Additional Requirements ===
Once you have the IDB file downloaded, you will need to add a .netrc in your home directory with the username and password to access the EOVSA cloud database. Please email someone in the NJIT radio group (http://ovsa.njit.edu/people.html) to request that information.

You will also need to install
#the '''suncasa''' python package (see the readme file at '''https://github.com/suncasa/suncasa-src''' for complete installation instructions),
#the '''eovsapy''' python package (see '''https://github.com/suncasa/eovsapy''' for installation instructions).

== Calibration on the Pipeline computer at OVRO ==
=== Connection details to pipeline server ===
One can use the Mobaxterm platform to connect to the Pipeline server through a Windows machine or use SSH through a Mac machine.

==== Step 0: First time pipeline environment setup====

First time users of pipelines ipython environment should

1. add the following line to ~/.bashrc (ex /home/shaheda/.bashrc not in your /data1/ folder)

<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
alias loadpyenv3.8='source /home/user/.setenv_pyenv38'
</pre>

2. run the following line
<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
cp /home/user/.netrc ~/
</pre>

==== Step 1: Importing to CASA from raw data (IDB) on the Pipeline machine====

In Python on the Pipeline machine, which has the complete EOVSA SQL database. (bash; load pyenv3.8; ipython)

If you are not using mobaxterm, directly SSH to Pipeline through your Linux or Mac computer.

<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">

from suncasa.suncasatasks import calibeovsa
from suncasa.suncasatasks import importeovsa
from casatasks import split
from eovsapy.read_idb import get_trange_files
from eovsapy.util import Time
import numpy as np
import os

trange = Time(['2017-08-21 20:15:00', '2017-08-21 20:35:00']) ###Change accordingly###
files = get_trange_files(trange)

outpath = './msdata/' ###Change accordingly###
if not os.path.exists(outpath):
os.makedirs(outpath)

msfiles = importeovsa(idbfiles=files, ncpu=1, timebin="0s", width=1,
visprefix=outpath,
nocreatms=False, doconcat=False,
modelms="", doscaling=False, keep_nsclms=False, udb_corr=True)
</pre>

If you come across errors with calibeovsa, add following lines to your ~/.casa/init.py file.
<pre style="background-color: #FCEBD9">
import sys
sys.path.append('/common/python')
sys.path.append('/common/python/packages/pipeline_casa')
execfile('/common/python/suncasa/tasks/mytasks.py')
</pre>

==== Step 2: Concatenate all the 10 mins data, if there are any====
Follow this step if there are more than one .ms files, if not run step 3 directly. If doimage=True, a quicklook image will be produced (by integrating over the entire time) as shown below. If Step 2 is used, skip the calibeovsa in Step 3 (you already did it when you concat)
<pre style="background-color: #FCEBD9">
# This is to set the path/name for the concatenated files
concatvis = os.path.basename(msfiles[0])[:11] + '_concat_cal.ms'
vis = calibeovsa(msfiles, doconcat=True, concatvis=concatvis, caltype=['refpha','phacal'], doimage=False)
</pre>

[[file:Figure1_imagingtutorial.png|frame|right|800px|'''Figure 1:''' Quick-look full-Sun image after the initial calibration.]]

==== Step 3: Calibration ====
This will calibrate the input visibility, write out calibration tables under /data1/eovsa/caltable/, and apply the calibration.
<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
vis = calibeovsa(msfiles, caltype=['refpha','phacal'], doimage=False) ###Change the vis filename accordingly###
# Append '_cal' to the ms filename and split the corrected column to the new caled ms
vis_str = str(' '.join(vis))
caled_vis=vis_str.replace('.ms','_cal.ms')
split(vis=' '.join(vis),outputvis=caled_vis,datacolumn='corrected',timerange='',correlation='XX')
</pre>

One needs to transfer the created caled ms data files (xxx_concat_cal.ms or xxx_cal.ms) from pipeline to inti server, which has all the casatasks installed, in order to run the rest of the imaging steps.

=== Connection details to Inti server ===
For Windows, on Mobaxterm,

#With your NJIT VPN connected, connect to one of the afsconnect servers (for example, afsaccess3.njit.edu) using your UCID and password.
#ssh -X UCID@inti.hpcnet.campus.njit.edu

To avoid typing the full inti address each time you attempt for ssh, you may wish to add the following lines with your username to C:\Program Files\Git\etc\ssh\ssh_config on Windows and /.ssh/config on Mac and Linux machines.

<pre style="background-color: #FCEBD9">
Host inti
Hostname inti.hpcnet.campus.njit.edu
User USERNAME ###Insert UCID/inti username here###
</pre>

To have sufficient disk space with EOVSA data analysis over Inti, use your dedicated directory YOURDIRECTORY at the location given below. If you do not have a directory, Please take help from Sijie in creating one.
<pre style="background-color: #FCEBD9">
cd /inti/data/users/YOURDIRECTORY
</pre>

For Linux or Mac machine,
ssh -X UCID@inti.hpcnet.campus.njit.edu

=== Transferring data files between servers ===
For directly transferring your calibrated .ms data between the Pipeline and Inti servers, follow the below given steps.
<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
1. Log into Inti using your username.
ssh -X USERNAME@inti.hpcnet.campus.njit.edu

Then create a tunnel into Pipeline from Inti.
ssh -L 8888:pipeline.solar.pvt:22 guest@ovsa.njit.edu

2. Log into Inti again from a new terminal.

Change to your working directory and give this command to copy your data on Pipeline.
scp -v -C -r -P 8888 USERNAMEofPipeline@localhost:PATHofMSDATA/MSfilename ./
Eg: scp -v -C -r -P 8888 shaheda@localhost:/data1/shaheda/IDB20220118173922_cal.ms ./
where, MSfilename, PATHofMSDATA are your .ms data and its path on Pipeline machine.
</pre>

Alternatively, one can follow the below procedure to do the transfer.

For Windows, on mobaxterm, drag and drop the ms file to your local machine or use scp command as given below.

<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
scp -r -C userid@pipeline:/your/folder/msfile /localmachine/destination/folder/
</pre>

On mobaxterm and on your local terminal, use the following command to finally copy the ms file to Inti.

<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
scp -r -C /localmachine/destination/folder/msfile UCID@inti.hpcnet.campus.njit.edu:/inti/data/users/YOURDIRECTORY
</pre>

For Mac and Linux, SCP can be used in the same way. Add the following lines to your SSH config file, to bypass ovsa.njit.edu from copying.
vi ~/.ssh/config
<pre style="background-color: #FCEBD9">
Host ovsa
HostName ovsa.njit.edu
User guest
Host pipeline
Hostname pipeline.solar.pvt
User userid
ProxyCommand ssh -W %h:%p guest@ovsa.njit.edu
</pre>

=== Software details on the servers ===
On Inti,
when logging in for the first time, please add the following lines to your accounts ~/.bashrc file.

>>vi ~/.bashrc
Insert the text given below and save it.

<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
#### setting start ####
if [ $HOSTNAME == "baozi.hpcnet.campus.njit.edu" ]; then
source /srg/.setenv_baozi
fi
if [ $HOSTNAME == "inti.hpcnet.campus.njit.edu" ]; then
source /inti/.setenv_inti
fi
if [ $HOSTNAME == "guko.resource.campus.njit.edu" ]; then
source /data/data/.setenv_guko
fi
#### setting end ####
</pre>

Both CASA 5 and 6 are available on Inti.

Enter the bash environment on inti, and load the desired casa environment.
To load CASA 5, enter bash environment by giving >>bash
<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
>> loadcasa5
>> suncasa #This should load the software making you ready for the analysis
</pre>

Or to load CASA 6, enter bash environment by giving >>bash
<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
>> loadcasa6
>> ipython #This should load the software making you ready for the analysis
</pre>
Here, for example, to use clean, first start ipython as given above, then type in >>from casatasks import tclean

====Step 4: Self-calibration====
[[file:Figure3_imagingtutorial.png|thumb|center|500px|Figure 2: Cotton-Schwab clean major and minor cycles. [Source: http://www.aoc.nrao.edu/~rurvashi/ImagingAlgorithmsInCasa/node2.html].]]
Follow the below given steps to run the self-calibration of the imaging data and produce the calibrated images in .fits format. https://github.com/binchensun/casa-eovsa/blob/master/slfcal_example.py

<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
from suncasa.utils import helioimage2fits as hf
import os
import numpy as np
import pickle
from matplotlib import gridspec as gridspec
from sunpy import map as smap
from matplotlib import pyplot as plt
from split_cli import split_cli as split
import time

# =========== task handlers =============
dofullsun = 1 # initial full-sun imaging ###Change accordingly###
domasks=1 # get masks ###Change accordingly###
doslfcal=1 # main cycle of doing selfcalibration ###Change accordingly###
doapply=1 # apply the results ###Change accordingly###
doclean_slfcaled=1 # perform clean for self-calibrated data ###Change accordingly###

# ============ declaring the working directories ============
workdir = os.getcwd()+'/' #main working directory. Using current directory in this example
slfcaldir = workdir+'slfcal/' #place to put all selfcalibration products
imagedir = slfcaldir+'images/' #place to put all selfcalibration images
maskdir = slfcaldir+'masks/' #place to put clean masks
imagedir_slfcaled = slfcaldir+'images_slfcaled/' #place to put final self-calibrated images
caltbdir = slfcaldir+'caltbs/' # place to put calibration tables
# make these directories if they do not already exist
dirs = [workdir, slfcaldir, imagedir, maskdir, imagedir_slfcaled, caltbdir]
for d in dirs:
if not os.path.exists(d):
os.makedirs(d)

# ============ Split a short time for self-calibration ===========
# input visibility
ms_in = workdir + 'IDB20170821202020_cal.ms' ###Change the initial calibrated (through calibeovsa) vis accordingly###
# output, selfcaled, visibility
ms_slfcaled = workdir + os.path.basename(ms_in).replace('cal','slfcaled')
# intermediate small visibility for selfcalbration
# selected time range for generating self-calibration solutions
trange='2017/08/21/20:21:10~2017/08/21/20:21:30' ###Change accordingly###
slfcalms = slfcaldir+'slfcalms.XX.slfcal'
slfcaledms = slfcaldir+'slfcalms.XX.slfcaled'
if not os.path.exists(slfcalms):
split(vis=ms_in,outputvis=slfcalms,datacolumn='data',timerange=trange,correlation='XX')

# ============ Prior definitions for spectral windows, antennas, pixel numbers =========
spws=[str(s+1) for s in range(30)] ###spws=[str(s+1) for s in range(49)] # For post-2020 data
antennas='0~12&0~12'
npix=512
nround=3 #number of slfcal cycles
</pre>

=====4.1=====
<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
# =========== Step 1, doing a full-Sun image to find out phasecenter and appropriate field of view =========
if dofullsun:
#initial mfs clean to find out the image phase center
im_init='fullsun_init'
os.system('rm -rf '+im_init+'*')
tclean(vis=slfcalms,
antenna=antennas,
imagename=im_init,
spw='1~15',
specmode='mfs',
timerange=trange,
imsize=[npix],
cell=['5arcsec'],
niter=1000,
gain=0.05,
stokes='I',
restoringbeam=['30arcsec'],
interactive=False,
pbcor=True)

hf.imreg(vis=slfcalms,imagefile=im_init+'.image.pbcor',fitsfile=im_init+'.fits',
timerange=trange,usephacenter=False,verbose=True)
clnjunks = ['.flux', '.mask', '.model', '.psf', '.residual','.sumwt','.pb','.image'] #Do not run the next 4 lines if needed to view and assess the subset of clean process images
for clnjunk in clnjunks:
if os.path.exists(im_init + clnjunk):
os.system('rm -rf '+im_init + clnjunk)

from sunpy import map as smap
from matplotlib import pyplot as plt
fig = plt.figure(figsize=(6,6))
ax = fig.add_subplot(111)
eomap=smap.Map(im_init+'.fits')
#eomap.data=eomap.data.reshape((npix,npix))
eomap.plot_settings['cmap'] = plt.get_cmap('jet')
eomap.plot(axes = ax)
eomap.draw_limb()
plt.show()
viewer(im_init+'.image.pbcor')
</pre>
[[file:Figure2_imagingtutorial.png|thumb|center|500px|Figure 3: Full-Sun image after initial clean to find the flare location.]]

=====4.2=====
<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
# parameters specific to the event (found from step 1)
phasecenter='J2000 10h02m59 11d58m07' ###Change accordingly###
xran=[280,480] ###Change accordingly###
yran=[-50,150] ###Change accordingly###

# =========== Step 2 (optional), generate masks =========
# if skipped, will not use any masks
if domasks:
clearcal(slfcalms)
delmod(slfcalms)
antennas=antennas
pol='XX'
imgprefix=maskdir+'slf_t0'

# step 1: set up the clean masks
img_init=imgprefix+'_init_ar_'
os.system('rm -rf '+img_init+'*')
#spwrans_mask=['1~5','6~12','13~20','21~30']
spwrans_mask=['1~12']
#convert to a list of spws
spwrans_mask_list = [[str(i) for i in (np.arange(int(m.split('~')[0]),int(m.split('~')[1])))] for m in spwrans_mask] # Not used?
masks=[]
imnames=[]
for spwran in spwrans_mask:
imname=img_init+spwran.replace('~','-')
try:
tclean(vis=slfcalms,
antenna=antennas,
imagename=imname,
spw=spwran,
specmode='mfs',
timerange=trange,
imsize=[npix],
cell=['2arcsec'],
niter=1000,
gain=0.05,
stokes='XX',
restoringbeam=['20arcsec'],
phasecenter=phasecenter,
weighting='briggs',
robust=1.0,
interactive=True,
datacolumn='data',
pbcor=True,
savemodel='modelcolumn')
imnames.append(imname+'.image')
masks.append(imname+'.mask')
clnjunks = ['.flux', '.model', '.psf', '.residual'] #Do not run the next 4 lines if needed to view and assess the subset of clean process images
for clnjunk in clnjunks:
if os.path.exists(imname + clnjunk):
os.system('rm -rf '+ imname + clnjunk)
except:
print('error in cleaning spw: '+spwran)

pickle.dump(masks,open(slfcaldir+'masks.p','wb'))
</pre>
[[file:Figure4_imagingtutorial.PNG|thumb|center|800px|Figure 4: Interactive clean window to create masks over the source. The white outline surrounding the source is the mask selected by the polygon drawing option.]]

The outlines drawn for masks can be created by any of the icons with the letter 'R' in the Viewer window. The instructions for doing this can be found by hovering over those icons.

=====4.3=====
<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
# =========== Step 3, main step of selfcalibration =========
if doslfcal:
if os.path.exists(slfcaldir+'masks.p'):
masks=pickle.load(open(slfcaldir+'masks.p','rb'))
if not os.path.exists(slfcaldir+'masks.p'):
print 'masks do not exist. Use default mask'
masks=[]
os.system('rm -rf '+imagedir+'*')
os.system('rm -rf '+caltbdir+'*')
#first step: make a mock caltable for the entire database
print('Processing ' + trange)
slftbs=[]
calprefix=caltbdir+'slf'
imgprefix=imagedir+'slf'
tb.open(slfcalms+'/SPECTRAL_WINDOW')
reffreqs=tb.getcol('REF_FREQUENCY')
bdwds=tb.getcol('TOTAL_BANDWIDTH')
cfreqs=reffreqs+bdwds/2.
tb.close()
# starting beam size at 3.4 GHz in arcsec #Change accordingly
sbeam=40.
strtmp=[m.replace(':','') for m in trange.split('~')]
timestr='t'+strtmp[0]+'-'+strtmp[1]
refantenna='0'
# number of iterations for each round
niters=[100, 300, 500]
# roburst value for weighting the baselines
robusts=[1.0, 0.5, 0.0]
# apply calibration tables? Set to true for most cases
doapplycal=[1,1,1]
# modes for calibration, 'p' for phase-only, 'a' for amplitude only, 'ap' for both
calmodes=['p','p','a']
# setting uvranges for model image (optional, not used here)
uvranges=['','','']
for n in range(nround):
slfcal_tb_g= calprefix+'.G'+str(n)
fig = plt.figure(figsize=(8.4,7.)) # fig = plt.figure(figsize=(14, 7)) # For post-2020 data (50 spws)
gs = gridspec.GridSpec(5, 6) # gs = gridspec.GridSpec(5, 10) # For post-2020 data (50 spws)
for s,sp in enumerate(spws):
print 'processing spw: '+sp
cfreq=cfreqs[int(sp)]
# setting restoring beam size (not very useful for selfcal anyway, but just to see the results)
bm=max(sbeam*cfreqs[1]/cfreq, 6.)
slfcal_img = imgprefix+'.spw'+sp.zfill(2)+'.slfcal'+str(n)
# only the first round uses nearby spws for getting initial model
if n == 0:
spbg=max(int(sp)-2,1) # spbg=max(int(sp)-2,0) # For post-2020 data (50 spws)
sped=min(int(sp)+2,30) # sped=min(int(sp)+2,49) # For post-2020 data (50 spws)
spwran=str(spbg)+'~'+str(sped)
print('using spw {0:s} as model'.format(spwran))
if 'spwrans_mask' in vars():
for m, spwran_mask in enumerate(spwrans_mask):
if sp in spwran_mask:
mask = masks[m]
print('using mask {0:s}'.format(mask))
findmask = True
if not findmask:
print('mask not found. Do use any masks')
else:
spwran = sp
if 'spwrans_mask' in vars():
for m, spwran_mask in enumerate(spwrans_mask):
if sp in spwran_mask:
mask = masks[m]
print 'using mask {0:s}'.format(mask)
findmask = True
if not findmask:
print('mask not found. Do use any masks')
try:
tclean(vis=slfcalms,
antenna=antennas,
imagename=slfcal_img,
uvrange=uvranges[n],
spw=spwran,
specmode='mfs',
timerange=trange,
imsize=[npix],
cell=['2arcsec'],
niter=niters[n],
gain=0.05,
stokes='XX', #use pol XX image as the model
weighting='briggs',
robust=robusts[n],
phasecenter=phasecenter,
mask=mask,
restoringbeam=[str(bm)+'arcsec'],
pbcor=False,
interactive=False,
savemodel='modelcolumn')
if os.path.exists(slfcal_img+'.image'):
fitsfile=slfcal_img+'.fits'
hf.imreg(vis=slfcalms,imagefile=slfcal_img+'.image',fitsfile=fitsfile,
timerange=trange,usephacenter=False,toTb=True,verbose=False,overwrite=True)
clnjunks = ['.mask','.flux', '.model', '.psf', '.residual', '.image','.pb','.image.pbcor','.sumwt'] #Do not run the next 4 lines if needed to view and assess the subset of clean process images
for clnjunk in clnjunks:
if os.path.exists(slfcal_img + clnjunk):
os.system('rm -rf '+ slfcal_img + clnjunk)
ax = fig.add_subplot(gs[s])
eomap=smap.Map(fitsfile)
eomap.plot_settings['cmap'] = plt.get_cmap('jet')
eomap.plot(axes = ax)
eomap.draw_limb()
#eomap.draw_grid()
ax.set_title(' ')
ax.get_xaxis().set_visible(False)
ax.get_yaxis().set_visible(False)
ax.set_xlim(xran)
ax.set_ylim(yran)
plt.pause(0.5) # Allows viewing of each image as it is plotted.
os.system('rm -f '+ fitsfile)

except:
print 'error in cleaning spw: '+sp
print 'using nearby spws for initial model'
sp_e=int(sp)+2
sp_i=int(sp)-2
if sp_i < 1: # if sp < 0: # For post-2020 data (50 spws)
sp_i = 1 # sp_i = 0 # For post-2020 data (50 spws)
if sp_e > 30: # if sp_e > 49: # For post-2020 data (50 spws)
sp_e = 30 # sp_e = 49 # For post-2020 data (50 spws)
sp_=str(sp_i)+'~'+str(sp_e)
try:
tget(tclean)
spw=sp_
print('using spw {0:s} as model'.format(sp_))
tclean()
except:
print 'still not successful. abort...'
break

gaincal(vis=slfcalms, refant=refantenna,antenna=antennas,caltable=slfcal_tb_g,spw=sp, uvrange='',\
gaintable=[],selectdata=True,timerange=trange,solint='inf',gaintype='G',calmode=calmodes[n],\
combine='',minblperant=4,minsnr=2,append=True)
if not os.path.exists(slfcal_tb_g):
print 'No solution found in spw: '+sp
figname=imagedir+'slf_t0_n{:d}.png'.format(n)
plt.subplots_adjust(left=0, bottom=0, right=1, top=1, wspace=0, hspace=0)
plt.savefig(figname)
time.sleep(10)
plt.close()

if os.path.exists(slfcal_tb_g):
slftbs.append(slfcal_tb_g)
slftb=[slfcal_tb_g]
os.chdir(slfcaldir)
if calmodes[n] == 'p':
plotcal(caltable=slfcal_tb_g,antenna='1~12',xaxis='freq',yaxis='phase',\
subplot=431,plotrange=[-1,-1,-180,180],iteration='antenna',figfile=slfcal_tb_g+'.png',showgui=False)
if calmodes[n] == 'a':
plotcal(caltable=slfcal_tb_g,antenna='1~12',xaxis='freq',yaxis='amp',\
subplot=431,plotrange=[-1,-1,0,2.],iteration='antenna',figfile=slfcal_tb_g+'.png',showgui=False)
os.chdir(workdir)
plt.pause(0.5) # Allows viewing of the plot

if doapplycal[n]:
clearcal(slfcalms)
delmod(slfcalms)
applycal(vis=slfcalms,gaintable=slftb,spw=','.join(spws),selectdata=True,\
antenna=antennas,interp='nearest',flagbackup=False,applymode='calonly',calwt=False)

if n < nround-1:
prompt=raw_input('Continuing to selfcal?')
#prompt='y'
if prompt.lower() == 'n':
if os.path.exists(slfcaledms):
os.system('rm -rf '+slfcaledms)
split(slfcalms,slfcaledms,datacolumn='corrected')
print 'Final calibrated ms is {0:s}'.format(slfcaledms)
break
if prompt.lower() == 'y':
slfcalms_=slfcalms+str(n)
if os.path.exists(slfcalms_):
os.system('rm -rf '+slfcalms_)
split(slfcalms,slfcalms_,datacolumn='corrected')
slfcalms=slfcalms_
else:
if os.path.exists(slfcaledms):
os.system('rm -rf '+slfcaledms)
split(slfcalms,slfcaledms,datacolumn='corrected')
print 'Final calibrated ms is {0:s}'.format(slfcaledms)
</pre>

=====4.4=====
<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
# =========== Step 4: Apply self-calibration tables =========
if doapply:
import glob
os.chdir(workdir)
clearcal(ms_in)
clearcal(slfcalms)
applycal(vis=slfcalms,gaintable=slftbs,spw=','.join(spws),selectdata=True,\
antenna=antennas,interp='linear',flagbackup=False,applymode='calonly',calwt=False)
applycal(vis=ms_in,gaintable=slftbs,spw=','.join(spws),selectdata=True,\
antenna=antennas,interp='linear',flagbackup=False,applymode='calonly',calwt=False)
if os.path.exists(ms_slfcaled):
os.system('rm -rf '+ms_slfcaled)
split(ms_in, ms_slfcaled,datacolumn='corrected')
</pre>
[[file:Slf.G0.png|thumb|center|500px|Figure 1: Phase before self-calibration]]
[[file:Slf.G1.png|thumb|center|500px|Figure 2: Phase after self-calibration]]

=====4.5=====
<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
# =========== Step 5: Generate final self-calibrated images (optional) =========
if doclean_slfcaled:
import glob
pol='XX'
print('Processing ' + trange)
img_final=imagedir_slfcaled+'/slf_final_{0}_t0'.format(pol)
vis = ms_slfcaled
tb.open(vis+'/SPECTRAL_WINDOW')
reffreqs=tb.getcol('REF_FREQUENCY')
bdwds=tb.getcol('TOTAL_BANDWIDTH')
cfreqs=reffreqs+bdwds/2.
tb.close()
sbeam=30.
from matplotlib import gridspec as gridspec
from sunpy import map as smap
from matplotlib import pyplot as plt
fitsfiles=[]
for s,sp in enumerate(spws):
cfreq=cfreqs[int(sp)]
bm=max(sbeam*cfreqs[1]/cfreq,4.)
imname=img_final+'_s'+sp.zfill(2)
fitsfile=imname+'.fits'
if not os.path.exists(fitsfile):
print 'cleaning spw {0:s} with beam size {1:.1f}"'.format(sp,bm)
try:
tclean(vis=vis,
antenna=antennas,
imagename=imname,
spw=sp,
specmode='mfs',
timerange=trange,
imsize=[npix],
cell=['1arcsec'],
niter=1000,
gain=0.05,
stokes=pol,
weighting='briggs',
robust=2.0,
restoringbeam=[str(bm)+'arcsec'],
phasecenter=phasecenter,
mask='',
pbcor=True,
interactive=False)
except:
print 'cleaning spw '+sp+' unsuccessful. Proceed to next spw'
continue
if os.path.exists(imname+'.image.pbcor'):
imn = imname+'.image.pbcor'
hf.imreg(vis=vis,imagefile=imn,fitsfile=fitsfile,
timerange=trange,usephacenter=False,toTb=True,verbose=False)
fitsfiles.append(fitsfile)
junks=['.flux','.model','.psf','.residual','.mask','.image','.pb','.image.pbcor','.sumwt'] #Do not run the next 4 lines if needed to view and assess the subset of clean process images
for junk in junks:
if os.path.exists(imname+junk):
os.system('rm -rf '+imname+junk)
else:
print('fits file '+fitsfile+' already exists, skip clean...')
fitsfiles.append(fitsfile)

fig = plt.figure(figsize=(8.4,7.)) # fig = plt.figure(figsize=(14, 7)) # For post-2020 data (50 spws)
gs = gridspec.GridSpec(5, 6) # gs = gridspec.GridSpec(5, 10) # For post-2020 data (50 spws)
for s,sp in enumerate(spws):
cfreq=cfreqs[int(sp)]
ax = fig.add_subplot(gs[s])
eomap=smap.Map(fitsfiles[s])
eomap.plot_settings['cmap'] = plt.get_cmap('jet')
eomap.plot(axes = ax)
eomap.draw_limb()
ax.set_title(' ')
ax.get_xaxis().set_visible(False)
ax.get_yaxis().set_visible(False)
ax.set_xlim(xran)
ax.set_ylim(yran)
plt.text(0.98,0.85,'{0:.1f} GHz'.format(cfreq/1e9),transform=ax.transAxes,ha='right',color='w',fontweight='bold')
plt.subplots_adjust(left=0, bottom=0, right=1, top=1, wspace=0, hspace=0)
plt.show()

</pre>
The .fits files of the self calibrated images at each frequency for the given time are saved at /slfcal/images_slfcaled in your working directory.

[[file:Slf_t0_n0.png|thumb|center|500px|Figure 3: Multi-frequency images before self-calibration]]
[[file:Slf_t0_n1.png|thumb|center|500px|Figure 4: Multi-frequency images after self-calibration]]

====Step 5: Quick-look imaging ==== 
For spectral imaging analysis of the event, follow [http://www.ovsa.njit.edu/wiki/index.php/EOVSA_Data_Analysis_Tutorial#Spectral_Imaging_with_SunCASA this tutorial] using the self-calibrated data obtained from the previous step or use [https://colab.research.google.com/drive/1lSLLxgOG6b8kgu9Sk6kSKvrViyubnXG6?usp=sharing#scrollTo=xbXyyLmCFCGL this link].

<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
from suncasa.utils import qlookplot as ql ## (Optional) Supply the npz file of the dynamic spectrum from previous step.
## If not provided, the program will generate a new one from the visibility.
## set the time interval
from suncasa import dspec as ds
import time
visibility_data = 'IDB20170821202020_slfcaled.ms'
specfile = visibility_data + '.dspec.npz'
d = ds.Dspec(visibility_data, bl='4&9', specfile=specfile)

timerange = '19:02:00~19:02:10' ## select frequency range from 2.5 GHz to 3.5 GHz
spw = '2~5' ## select stokes XX
stokes = 'XX' ## turn off AIA image plotting, default is True
plotaia = False
xycen = [375, 45] ## image center for clean in solar X-Y in arcsec
cell=['2.0arcsec'] ## pixel size
imsize=[128] ## x and y image size in pixels.
fov = [100,100] ## field of view of the zoomed-in panels in unit of arcsec
spw = ['{}'.format(s) for s in range(1,31)]
clevels = [0.5, 1.0] ## contour levels to fill in between.
calpha=0.35 ## now tune down the alpha
restoringbeam=['6arcsec']
ql.qlookplot(vis=msfile, specfile=specfile, timerange=timerange, spw=spw, stokes=stokes, \
restoringbeam=restoringbeam,imsize=imsize,cell=cell, \
xycen=xycen,fov=fov,clevels=clevels,calpha=calpha)
</pre>

Tohban EOVSA Imaging Tutorial A-Z

2024-05-17T16:03:34Z

Dgary: /* Calibration on your own computer */

This tutorial describes the step-by-step procedure to download EOVSA IDB data, obtain and calibrate the measurement sets (.ms), and, transfer them to the inti server for self-calibration and further analysis.

'''Pre-requisites:''' Accounts on Pipeline and Inti or Baozi servers.

== Calibration on your own computer ==
[[File: Quick_Start.png|thumb|600px|Once you have downloaded an IDB file and installed both suncasa and eovsapy on your own computer, you can create a calibrated CASA measurement set with these minimal commands at the ipython command line:

<pre>
from suncasa.suncasatasks import calibeovsa
from suncasa.suncasatasks import importeovsa
try:
# Required in modular casa, but fails in stand-alone casa
from casatasks import split
except:
pass
idbfile = <IDB filename> # The path and filename of the IDB file
msfiles = importeovsa(idbfiles=idbfile)
vis, = calibeovsa(msfiles, caltype=['refpha','phacal'])
outvis = vis.replace('.ms','_cal.ms')
split(vis=vis, outputvis=outvis, correlation='XX')
</pre>

If all goes well, this will result in a fully-calibrated visibility dataset with the string "_cal.ms" appended to the IDB filename, located in the same place as the original IDB file. You can then start with Step 4 below, for self-calibration.
]]
It is now possible to do the entire calibration procedure from anywhere by copying to your local computer one or more raw interim database (IDB) files in Miriad format and calibrating them from a cloud database. Here are the steps. First, find the IDB file(s) of interest. The IDB files are all available online at the following links:

* '''2017 Apr - present - 7 days: https://research.ssl.berkeley.edu/data/eovsa/'''
* '''2024 Jan - present: http://ovsa.njit.edu/fits/IDB/'''

Once you have the file(s) identified, copy them to your local computer. One way to do that is with the wget command:
<pre> wget -r --no-parent -nH --cut-dirs=3 -e robots="off" -R "index.html*" <URL> </pre>
where <URL> is the path to the file(s). For example, to get the data for the flare at 2022 Nov 18 22:04 UT [http://www.ovsa.njit.edu/wiki/images/8/8c/EOVSA_20221118_C1flare.png] the URL would be http://ovsa.njit.edu/IDB2/20221118/IDB20221118215521/. Warning, these IDB "files" are actually directories, so include the trailing / in the URL or else you will transfer the entire day's data (many GB of data!). An easy way to get the URL is simply to right-click on the web link for the file and "copy link address."

=== Additional Requirements ===
Once you have the IDB file downloaded, you will need to add a .netrc in your home directory with the username and password to access the EOVSA cloud database. Please email someone in the NJIT radio group (http://ovsa.njit.edu/people.html) to request that information.

You will also need to install
#the '''suncasa''' python package (see the readme file at '''https://github.com/suncasa/suncasa-src''' for complete installation instructions),
#the '''eovsapy''' python package (see '''https://github.com/suncasa/eovsapy''' for installation instructions).

== Calibration on the Pipeline computer at OVRO ==
=== Connection details to pipeline server ===
One can use the Mobaxterm platform to connect to the Pipeline server through a Windows machine or use SSH through a Mac machine.

==== Step 0: First time pipeline environment setup====

First time users of pipelines ipython environment should

1. add the following line to ~/.bashrc (ex /home/shaheda/.bashrc not in your /data1/ folder)

<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
alias loadpyenv3.8='source /home/user/.setenv_pyenv38'
</pre>

2. run the following line
<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
cp /home/user/.netrc ~/
</pre>

==== Step 1: Importing to CASA from raw data (IDB) on the Pipeline machine====

In Python on the Pipeline machine, which has the complete EOVSA SQL database. (bash; load pyenv3.8; ipython)

If you are not using mobaxterm, directly SSH to Pipeline through your Linux or Mac computer.

<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">

from suncasa.suncasatasks import calibeovsa
from suncasa.suncasatasks import importeovsa
from casatasks import split
from eovsapy.read_idb import get_trange_files
from eovsapy.util import Time
import numpy as np
import os

trange = Time(['2017-08-21 20:15:00', '2017-08-21 20:35:00']) ###Change accordingly###
files = get_trange_files(trange)

outpath = './msdata/' ###Change accordingly###
if not os.path.exists(outpath):
os.makedirs(outpath)

msfiles = importeovsa(idbfiles=files, ncpu=1, timebin="0s", width=1,
visprefix=outpath,
nocreatms=False, doconcat=False,
modelms="", doscaling=False, keep_nsclms=False, udb_corr=True)
</pre>

If you come across errors with calibeovsa, add following lines to your ~/.casa/init.py file.
<pre style="background-color: #FCEBD9">
import sys
sys.path.append('/common/python')
sys.path.append('/common/python/packages/pipeline_casa')
execfile('/common/python/suncasa/tasks/mytasks.py')
</pre>

==== Step 2: Concatenate all the 10 mins data, if there are any====
Follow this step if there are more than one .ms files, if not run step 3 directly. If doimage=True, a quicklook image will be produced (by integrating over the entire time) as shown below. If Step 2 is used, skip the calibeovsa in Step 3 (you already did it when you concat)
<pre style="background-color: #FCEBD9">
# This is to set the path/name for the concatenated files
concatvis = os.path.basename(msfiles[0])[:11] + '_concat_cal.ms'
vis = calibeovsa(msfiles, doconcat=True, concatvis=concatvis, caltype=['refpha','phacal'], doimage=False)
</pre>

[[file:Figure1_imagingtutorial.png|frame|right|800px|'''Figure 1:''' Quick-look full-Sun image after the initial calibration.]]

==== Step 3: Calibration ====
This will calibrate the input visibility, write out calibration tables under /data1/eovsa/caltable/, and apply the calibration.
<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
vis = calibeovsa(msfiles, caltype=['refpha','phacal'], doimage=False) ###Change the vis filename accordingly###
# Append '_cal' to the ms filename and split the corrected column to the new caled ms
vis_str = str(' '.join(vis))
caled_vis=vis_str.replace('.ms','_cal.ms')
split(vis=' '.join(vis),outputvis=caled_vis,datacolumn='corrected',timerange='',correlation='XX')
</pre>

One needs to transfer the created caled ms data files (xxx_concat_cal.ms or xxx_cal.ms) from pipeline to inti server, which has all the casatasks installed, in order to run the rest of the imaging steps.

=== Connection details to Inti server ===
For Windows, on Mobaxterm,

#With your NJIT VPN connected, connect to one of the afsconnect servers (for example, afsaccess3.njit.edu) using your UCID and password.
#ssh -X UCID@inti.hpcnet.campus.njit.edu

To avoid typing the full inti address each time you attempt for ssh, you may wish to add the following lines with your username to C:\Program Files\Git\etc\ssh\ssh_config on Windows and /.ssh/config on Mac and Linux machines.

<pre style="background-color: #FCEBD9">
Host inti
Hostname inti.hpcnet.campus.njit.edu
User USERNAME ###Insert UCID/inti username here###
</pre>

To have sufficient disk space with EOVSA data analysis over Inti, use your dedicated directory YOURDIRECTORY at the location given below. If you do not have a directory, Please take help from Sijie in creating one.
<pre style="background-color: #FCEBD9">
cd /inti/data/users/YOURDIRECTORY
</pre>

For Linux or Mac machine,
ssh -X UCID@inti.hpcnet.campus.njit.edu

=== Transferring data files between servers ===
For directly transferring your calibrated .ms data between the Pipeline and Inti servers, follow the below given steps.
<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
1. Log into Inti using your username.
ssh -X USERNAME@inti.hpcnet.campus.njit.edu

Then create a tunnel into Pipeline from Inti.
ssh -L 8888:pipeline.solar.pvt:22 guest@ovsa.njit.edu

2. Log into Inti again from a new terminal.

Change to your working directory and give this command to copy your data on Pipeline.
scp -v -C -r -P 8888 USERNAMEofPipeline@localhost:PATHofMSDATA/MSfilename ./
Eg: scp -v -C -r -P 8888 shaheda@localhost:/data1/shaheda/IDB20220118173922_cal.ms ./
where, MSfilename, PATHofMSDATA are your .ms data and its path on Pipeline machine.
</pre>

Alternatively, one can follow the below procedure to do the transfer.

For Windows, on mobaxterm, drag and drop the ms file to your local machine or use scp command as given below.

<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
scp -r -C userid@pipeline:/your/folder/msfile /localmachine/destination/folder/
</pre>

On mobaxterm and on your local terminal, use the following command to finally copy the ms file to Inti.

<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
scp -r -C /localmachine/destination/folder/msfile UCID@inti.hpcnet.campus.njit.edu:/inti/data/users/YOURDIRECTORY
</pre>

For Mac and Linux, SCP can be used in the same way. Add the following lines to your SSH config file, to bypass ovsa.njit.edu from copying.
vi ~/.ssh/config
<pre style="background-color: #FCEBD9">
Host ovsa
HostName ovsa.njit.edu
User guest
Host pipeline
Hostname pipeline.solar.pvt
User userid
ProxyCommand ssh -W %h:%p guest@ovsa.njit.edu
</pre>

=== Software details on the servers ===
On Inti,
when logging in for the first time, please add the following lines to your accounts ~/.bashrc file.

>>vi ~/.bashrc
Insert the text given below and save it.

<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
#### setting start ####
if [ $HOSTNAME == "baozi.hpcnet.campus.njit.edu" ]; then
source /srg/.setenv_baozi
fi
if [ $HOSTNAME == "inti.hpcnet.campus.njit.edu" ]; then
source /inti/.setenv_inti
fi
if [ $HOSTNAME == "guko.resource.campus.njit.edu" ]; then
source /data/data/.setenv_guko
fi
#### setting end ####
</pre>

Both CASA 5 and 6 are available on Inti.

Enter the bash environment on inti, and load the desired casa environment.
To load CASA 5, enter bash environment by giving >>bash
<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
>> loadcasa5
>> suncasa #This should load the software making you ready for the analysis
</pre>

Or to load CASA 6, enter bash environment by giving >>bash
<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
>> loadcasa6
>> ipython #This should load the software making you ready for the analysis
</pre>
Here, for example, to use clean, first start ipython as given above, then type in >>from casatasks import tclean

====Step 4: Self-calibration====
[[file:Figure3_imagingtutorial.png|thumb|center|500px|Figure 2: Cotton-Schwab clean major and minor cycles. [Source: http://www.aoc.nrao.edu/~rurvashi/ImagingAlgorithmsInCasa/node2.html].]]
Follow the below given steps to run the self-calibration of the imaging data and produce the calibrated images in .fits format. https://github.com/binchensun/casa-eovsa/blob/master/slfcal_example.py

<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
from suncasa.utils import helioimage2fits as hf
import os
import numpy as np
import pickle
from matplotlib import gridspec as gridspec
from sunpy import map as smap
from matplotlib import pyplot as plt
from split_cli import split_cli as split
import time

# =========== task handlers =============
dofullsun = 1 # initial full-sun imaging ###Change accordingly###
domasks=1 # get masks ###Change accordingly###
doslfcal=1 # main cycle of doing selfcalibration ###Change accordingly###
doapply=1 # apply the results ###Change accordingly###
doclean_slfcaled=1 # perform clean for self-calibrated data ###Change accordingly###

# ============ declaring the working directories ============
workdir = os.getcwd()+'/' #main working directory. Using current directory in this example
slfcaldir = workdir+'slfcal/' #place to put all selfcalibration products
imagedir = slfcaldir+'images/' #place to put all selfcalibration images
maskdir = slfcaldir+'masks/' #place to put clean masks
imagedir_slfcaled = slfcaldir+'images_slfcaled/' #place to put final self-calibrated images
caltbdir = slfcaldir+'caltbs/' # place to put calibration tables
# make these directories if they do not already exist
dirs = [workdir, slfcaldir, imagedir, maskdir, imagedir_slfcaled, caltbdir]
for d in dirs:
if not os.path.exists(d):
os.makedirs(d)

# ============ Split a short time for self-calibration ===========
# input visibility
ms_in = workdir + 'IDB20170821202020_cal.ms' ###Change the initial calibrated (through calibeovsa) vis accordingly###
# output, selfcaled, visibility
ms_slfcaled = workdir + os.path.basename(ms_in).replace('cal','slfcaled')
# intermediate small visibility for selfcalbration
# selected time range for generating self-calibration solutions
trange='2017/08/21/20:21:10~2017/08/21/20:21:30' ###Change accordingly###
slfcalms = slfcaldir+'slfcalms.XX.slfcal'
slfcaledms = slfcaldir+'slfcalms.XX.slfcaled'
if not os.path.exists(slfcalms):
split(vis=ms_in,outputvis=slfcalms,datacolumn='data',timerange=trange,correlation='XX')

# ============ Prior definitions for spectral windows, antennas, pixel numbers =========
spws=[str(s+1) for s in range(30)] ###spws=[str(s+1) for s in range(49)] # For post-2020 data
antennas='0~12&0~12'
npix=512
nround=3 #number of slfcal cycles
</pre>

=====4.1=====
<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
# =========== Step 1, doing a full-Sun image to find out phasecenter and appropriate field of view =========
if dofullsun:
#initial mfs clean to find out the image phase center
im_init='fullsun_init'
os.system('rm -rf '+im_init+'*')
tclean(vis=slfcalms,
antenna=antennas,
imagename=im_init,
spw='1~15',
specmode='mfs',
timerange=trange,
imsize=[npix],
cell=['5arcsec'],
niter=1000,
gain=0.05,
stokes='I',
restoringbeam=['30arcsec'],
interactive=False,
pbcor=True)

hf.imreg(vis=slfcalms,imagefile=im_init+'.image.pbcor',fitsfile=im_init+'.fits',
timerange=trange,usephacenter=False,verbose=True)
clnjunks = ['.flux', '.mask', '.model', '.psf', '.residual','.sumwt','.pb','.image'] #Do not run the next 4 lines if needed to view and assess the subset of clean process images
for clnjunk in clnjunks:
if os.path.exists(im_init + clnjunk):
os.system('rm -rf '+im_init + clnjunk)

from sunpy import map as smap
from matplotlib import pyplot as plt
fig = plt.figure(figsize=(6,6))
ax = fig.add_subplot(111)
eomap=smap.Map(im_init+'.fits')
#eomap.data=eomap.data.reshape((npix,npix))
eomap.plot_settings['cmap'] = plt.get_cmap('jet')
eomap.plot(axes = ax)
eomap.draw_limb()
plt.show()
viewer(im_init+'.image.pbcor')
</pre>
[[file:Figure2_imagingtutorial.png|thumb|center|500px|Figure 3: Full-Sun image after initial clean to find the flare location.]]

=====4.2=====
<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
# parameters specific to the event (found from step 1)
phasecenter='J2000 10h02m59 11d58m07' ###Change accordingly###
xran=[280,480] ###Change accordingly###
yran=[-50,150] ###Change accordingly###

# =========== Step 2 (optional), generate masks =========
# if skipped, will not use any masks
if domasks:
clearcal(slfcalms)
delmod(slfcalms)
antennas=antennas
pol='XX'
imgprefix=maskdir+'slf_t0'

# step 1: set up the clean masks
img_init=imgprefix+'_init_ar_'
os.system('rm -rf '+img_init+'*')
#spwrans_mask=['1~5','6~12','13~20','21~30']
spwrans_mask=['1~12']
#convert to a list of spws
spwrans_mask_list = [[str(i) for i in (np.arange(int(m.split('~')[0]),int(m.split('~')[1])))] for m in spwrans_mask] # Not used?
masks=[]
imnames=[]
for spwran in spwrans_mask:
imname=img_init+spwran.replace('~','-')
try:
tclean(vis=slfcalms,
antenna=antennas,
imagename=imname,
spw=spwran,
specmode='mfs',
timerange=trange,
imsize=[npix],
cell=['2arcsec'],
niter=1000,
gain=0.05,
stokes='XX',
restoringbeam=['20arcsec'],
phasecenter=phasecenter,
weighting='briggs',
robust=1.0,
interactive=True,
datacolumn='data',
pbcor=True,
savemodel='modelcolumn')
imnames.append(imname+'.image')
masks.append(imname+'.mask')
clnjunks = ['.flux', '.model', '.psf', '.residual'] #Do not run the next 4 lines if needed to view and assess the subset of clean process images
for clnjunk in clnjunks:
if os.path.exists(imname + clnjunk):
os.system('rm -rf '+ imname + clnjunk)
except:
print('error in cleaning spw: '+spwran)

pickle.dump(masks,open(slfcaldir+'masks.p','wb'))
</pre>
[[file:Figure4_imagingtutorial.PNG|thumb|center|800px|Figure 4: Interactive clean window to create masks over the source. The white outline surrounding the source is the mask selected by the polygon drawing option.]]

The outlines drawn for masks can be created by any of the icons with the letter 'R' in the Viewer window. The instructions for doing this can be found by hovering over those icons.

=====4.3=====
<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
# =========== Step 3, main step of selfcalibration =========
if doslfcal:
if os.path.exists(slfcaldir+'masks.p'):
masks=pickle.load(open(slfcaldir+'masks.p','rb'))
if not os.path.exists(slfcaldir+'masks.p'):
print 'masks do not exist. Use default mask'
masks=[]
os.system('rm -rf '+imagedir+'*')
os.system('rm -rf '+caltbdir+'*')
#first step: make a mock caltable for the entire database
print('Processing ' + trange)
slftbs=[]
calprefix=caltbdir+'slf'
imgprefix=imagedir+'slf'
tb.open(slfcalms+'/SPECTRAL_WINDOW')
reffreqs=tb.getcol('REF_FREQUENCY')
bdwds=tb.getcol('TOTAL_BANDWIDTH')
cfreqs=reffreqs+bdwds/2.
tb.close()
# starting beam size at 3.4 GHz in arcsec #Change accordingly
sbeam=40.
strtmp=[m.replace(':','') for m in trange.split('~')]
timestr='t'+strtmp[0]+'-'+strtmp[1]
refantenna='0'
# number of iterations for each round
niters=[100, 300, 500]
# roburst value for weighting the baselines
robusts=[1.0, 0.5, 0.0]
# apply calibration tables? Set to true for most cases
doapplycal=[1,1,1]
# modes for calibration, 'p' for phase-only, 'a' for amplitude only, 'ap' for both
calmodes=['p','p','a']
# setting uvranges for model image (optional, not used here)
uvranges=['','','']
for n in range(nround):
slfcal_tb_g= calprefix+'.G'+str(n)
fig = plt.figure(figsize=(8.4,7.)) # fig = plt.figure(figsize=(14, 7)) # For post-2020 data (50 spws)
gs = gridspec.GridSpec(5, 6) # gs = gridspec.GridSpec(5, 10) # For post-2020 data (50 spws)
for s,sp in enumerate(spws):
print 'processing spw: '+sp
cfreq=cfreqs[int(sp)]
# setting restoring beam size (not very useful for selfcal anyway, but just to see the results)
bm=max(sbeam*cfreqs[1]/cfreq, 6.)
slfcal_img = imgprefix+'.spw'+sp.zfill(2)+'.slfcal'+str(n)
# only the first round uses nearby spws for getting initial model
if n == 0:
spbg=max(int(sp)-2,1) # spbg=max(int(sp)-2,0) # For post-2020 data (50 spws)
sped=min(int(sp)+2,30) # sped=min(int(sp)+2,49) # For post-2020 data (50 spws)
spwran=str(spbg)+'~'+str(sped)
print('using spw {0:s} as model'.format(spwran))
if 'spwrans_mask' in vars():
for m, spwran_mask in enumerate(spwrans_mask):
if sp in spwran_mask:
mask = masks[m]
print('using mask {0:s}'.format(mask))
findmask = True
if not findmask:
print('mask not found. Do use any masks')
else:
spwran = sp
if 'spwrans_mask' in vars():
for m, spwran_mask in enumerate(spwrans_mask):
if sp in spwran_mask:
mask = masks[m]
print 'using mask {0:s}'.format(mask)
findmask = True
if not findmask:
print('mask not found. Do use any masks')
try:
tclean(vis=slfcalms,
antenna=antennas,
imagename=slfcal_img,
uvrange=uvranges[n],
spw=spwran,
specmode='mfs',
timerange=trange,
imsize=[npix],
cell=['2arcsec'],
niter=niters[n],
gain=0.05,
stokes='XX', #use pol XX image as the model
weighting='briggs',
robust=robusts[n],
phasecenter=phasecenter,
mask=mask,
restoringbeam=[str(bm)+'arcsec'],
pbcor=False,
interactive=False,
savemodel='modelcolumn')
if os.path.exists(slfcal_img+'.image'):
fitsfile=slfcal_img+'.fits'
hf.imreg(vis=slfcalms,imagefile=slfcal_img+'.image',fitsfile=fitsfile,
timerange=trange,usephacenter=False,toTb=True,verbose=False,overwrite=True)
clnjunks = ['.mask','.flux', '.model', '.psf', '.residual', '.image','.pb','.image.pbcor','.sumwt'] #Do not run the next 4 lines if needed to view and assess the subset of clean process images
for clnjunk in clnjunks:
if os.path.exists(slfcal_img + clnjunk):
os.system('rm -rf '+ slfcal_img + clnjunk)
ax = fig.add_subplot(gs[s])
eomap=smap.Map(fitsfile)
eomap.plot_settings['cmap'] = plt.get_cmap('jet')
eomap.plot(axes = ax)
eomap.draw_limb()
#eomap.draw_grid()
ax.set_title(' ')
ax.get_xaxis().set_visible(False)
ax.get_yaxis().set_visible(False)
ax.set_xlim(xran)
ax.set_ylim(yran)
plt.pause(0.5) # Allows viewing of each image as it is plotted.
os.system('rm -f '+ fitsfile)

except:
print 'error in cleaning spw: '+sp
print 'using nearby spws for initial model'
sp_e=int(sp)+2
sp_i=int(sp)-2
if sp_i < 1: # if sp < 0: # For post-2020 data (50 spws)
sp_i = 1 # sp_i = 0 # For post-2020 data (50 spws)
if sp_e > 30: # if sp_e > 49: # For post-2020 data (50 spws)
sp_e = 30 # sp_e = 49 # For post-2020 data (50 spws)
sp_=str(sp_i)+'~'+str(sp_e)
try:
tget(tclean)
spw=sp_
print('using spw {0:s} as model'.format(sp_))
tclean()
except:
print 'still not successful. abort...'
break

gaincal(vis=slfcalms, refant=refantenna,antenna=antennas,caltable=slfcal_tb_g,spw=sp, uvrange='',\
gaintable=[],selectdata=True,timerange=trange,solint='inf',gaintype='G',calmode=calmodes[n],\
combine='',minblperant=4,minsnr=2,append=True)
if not os.path.exists(slfcal_tb_g):
print 'No solution found in spw: '+sp
figname=imagedir+'slf_t0_n{:d}.png'.format(n)
plt.subplots_adjust(left=0, bottom=0, right=1, top=1, wspace=0, hspace=0)
plt.savefig(figname)
time.sleep(10)
plt.close()

if os.path.exists(slfcal_tb_g):
slftbs.append(slfcal_tb_g)
slftb=[slfcal_tb_g]
os.chdir(slfcaldir)
if calmodes[n] == 'p':
plotcal(caltable=slfcal_tb_g,antenna='1~12',xaxis='freq',yaxis='phase',\
subplot=431,plotrange=[-1,-1,-180,180],iteration='antenna',figfile=slfcal_tb_g+'.png',showgui=False)
if calmodes[n] == 'a':
plotcal(caltable=slfcal_tb_g,antenna='1~12',xaxis='freq',yaxis='amp',\
subplot=431,plotrange=[-1,-1,0,2.],iteration='antenna',figfile=slfcal_tb_g+'.png',showgui=False)
os.chdir(workdir)
plt.pause(0.5) # Allows viewing of the plot

if doapplycal[n]:
clearcal(slfcalms)
delmod(slfcalms)
applycal(vis=slfcalms,gaintable=slftb,spw=','.join(spws),selectdata=True,\
antenna=antennas,interp='nearest',flagbackup=False,applymode='calonly',calwt=False)

if n < nround-1:
prompt=raw_input('Continuing to selfcal?')
#prompt='y'
if prompt.lower() == 'n':
if os.path.exists(slfcaledms):
os.system('rm -rf '+slfcaledms)
split(slfcalms,slfcaledms,datacolumn='corrected')
print 'Final calibrated ms is {0:s}'.format(slfcaledms)
break
if prompt.lower() == 'y':
slfcalms_=slfcalms+str(n)
if os.path.exists(slfcalms_):
os.system('rm -rf '+slfcalms_)
split(slfcalms,slfcalms_,datacolumn='corrected')
slfcalms=slfcalms_
else:
if os.path.exists(slfcaledms):
os.system('rm -rf '+slfcaledms)
split(slfcalms,slfcaledms,datacolumn='corrected')
print 'Final calibrated ms is {0:s}'.format(slfcaledms)
</pre>

=====4.4=====
<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
# =========== Step 4: Apply self-calibration tables =========
if doapply:
import glob
os.chdir(workdir)
clearcal(ms_in)
clearcal(slfcalms)
applycal(vis=slfcalms,gaintable=slftbs,spw=','.join(spws),selectdata=True,\
antenna=antennas,interp='linear',flagbackup=False,applymode='calonly',calwt=False)
applycal(vis=ms_in,gaintable=slftbs,spw=','.join(spws),selectdata=True,\
antenna=antennas,interp='linear',flagbackup=False,applymode='calonly',calwt=False)
if os.path.exists(ms_slfcaled):
os.system('rm -rf '+ms_slfcaled)
split(ms_in, ms_slfcaled,datacolumn='corrected')
</pre>
[[file:Slf.G0.png|thumb|center|500px|Figure 1: Phase before self-calibration]]
[[file:Slf.G1.png|thumb|center|500px|Figure 2: Phase after self-calibration]]

=====4.5=====
<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
# =========== Step 5: Generate final self-calibrated images (optional) =========
if doclean_slfcaled:
import glob
pol='XX'
print('Processing ' + trange)
img_final=imagedir_slfcaled+'/slf_final_{0}_t0'.format(pol)
vis = ms_slfcaled
tb.open(vis+'/SPECTRAL_WINDOW')
reffreqs=tb.getcol('REF_FREQUENCY')
bdwds=tb.getcol('TOTAL_BANDWIDTH')
cfreqs=reffreqs+bdwds/2.
tb.close()
sbeam=30.
from matplotlib import gridspec as gridspec
from sunpy import map as smap
from matplotlib import pyplot as plt
fitsfiles=[]
for s,sp in enumerate(spws):
cfreq=cfreqs[int(sp)]
bm=max(sbeam*cfreqs[1]/cfreq,4.)
imname=img_final+'_s'+sp.zfill(2)
fitsfile=imname+'.fits'
if not os.path.exists(fitsfile):
print 'cleaning spw {0:s} with beam size {1:.1f}"'.format(sp,bm)
try:
tclean(vis=vis,
antenna=antennas,
imagename=imname,
spw=sp,
specmode='mfs',
timerange=trange,
imsize=[npix],
cell=['1arcsec'],
niter=1000,
gain=0.05,
stokes=pol,
weighting='briggs',
robust=2.0,
restoringbeam=[str(bm)+'arcsec'],
phasecenter=phasecenter,
mask='',
pbcor=True,
interactive=False)
except:
print 'cleaning spw '+sp+' unsuccessful. Proceed to next spw'
continue
if os.path.exists(imname+'.image.pbcor'):
imn = imname+'.image.pbcor'
hf.imreg(vis=vis,imagefile=imn,fitsfile=fitsfile,
timerange=trange,usephacenter=False,toTb=True,verbose=False)
fitsfiles.append(fitsfile)
junks=['.flux','.model','.psf','.residual','.mask','.image','.pb','.image.pbcor','.sumwt'] #Do not run the next 4 lines if needed to view and assess the subset of clean process images
for junk in junks:
if os.path.exists(imname+junk):
os.system('rm -rf '+imname+junk)
else:
print('fits file '+fitsfile+' already exists, skip clean...')
fitsfiles.append(fitsfile)

fig = plt.figure(figsize=(8.4,7.)) # fig = plt.figure(figsize=(14, 7)) # For post-2020 data (50 spws)
gs = gridspec.GridSpec(5, 6) # gs = gridspec.GridSpec(5, 10) # For post-2020 data (50 spws)
for s,sp in enumerate(spws):
cfreq=cfreqs[int(sp)]
ax = fig.add_subplot(gs[s])
eomap=smap.Map(fitsfiles[s])
eomap.plot_settings['cmap'] = plt.get_cmap('jet')
eomap.plot(axes = ax)
eomap.draw_limb()
ax.set_title(' ')
ax.get_xaxis().set_visible(False)
ax.get_yaxis().set_visible(False)
ax.set_xlim(xran)
ax.set_ylim(yran)
plt.text(0.98,0.85,'{0:.1f} GHz'.format(cfreq/1e9),transform=ax.transAxes,ha='right',color='w',fontweight='bold')
plt.subplots_adjust(left=0, bottom=0, right=1, top=1, wspace=0, hspace=0)
plt.show()

</pre>
The .fits files of the self calibrated images at each frequency for the given time are saved at /slfcal/images_slfcaled in your working directory.

[[file:Slf_t0_n0.png|thumb|center|500px|Figure 3: Multi-frequency images before self-calibration]]
[[file:Slf_t0_n1.png|thumb|center|500px|Figure 4: Multi-frequency images after self-calibration]]

====Step 5: Quick-look imaging ==== 
For spectral imaging analysis of the event, follow [http://www.ovsa.njit.edu/wiki/index.php/EOVSA_Data_Analysis_Tutorial#Spectral_Imaging_with_SunCASA this tutorial] using the self-calibrated data obtained from the previous step or use [https://colab.research.google.com/drive/1lSLLxgOG6b8kgu9Sk6kSKvrViyubnXG6?usp=sharing#scrollTo=xbXyyLmCFCGL this link].

<pre style="background-color: #FCEBD9;overflow: auto;width: auto;">
from suncasa.utils import qlookplot as ql ## (Optional) Supply the npz file of the dynamic spectrum from previous step.
## If not provided, the program will generate a new one from the visibility.
## set the time interval
from suncasa import dspec as ds
import time
visibility_data = 'IDB20170821202020_slfcaled.ms'
specfile = visibility_data + '.dspec.npz'
d = ds.Dspec(visibility_data, bl='4&9', specfile=specfile)

timerange = '19:02:00~19:02:10' ## select frequency range from 2.5 GHz to 3.5 GHz
spw = '2~5' ## select stokes XX
stokes = 'XX' ## turn off AIA image plotting, default is True
plotaia = False
xycen = [375, 45] ## image center for clean in solar X-Y in arcsec
cell=['2.0arcsec'] ## pixel size
imsize=[128] ## x and y image size in pixels.
fov = [100,100] ## field of view of the zoomed-in panels in unit of arcsec
spw = ['{}'.format(s) for s in range(1,31)]
clevels = [0.5, 1.0] ## contour levels to fill in between.
calpha=0.35 ## now tune down the alpha
restoringbeam=['6arcsec']
ql.qlookplot(vis=msfile, specfile=specfile, timerange=timerange, spw=spw, stokes=stokes, \
restoringbeam=restoringbeam,imsize=imsize,cell=cell, \
xycen=xycen,fov=fov,clevels=clevels,calpha=calpha)
</pre>

2024 April

2024-04-28T11:40:11Z

Dgary: /* April 27 */

== April 01 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| -- || -- || -- || No Reference calibration; High winds.
|-
| -- || -- || -- || No Phase calibration; High winds.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 02 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| 10:15 || 79.3 || 1-9, 11-13 || Reference calibration successful; Ant7 (Bands<23); written to SQL (10:19 UT).
|-
| 15:54 || 15.7 || 1-6, 8-9, 11-13 || Phase calibration successful; written to SQL.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 03 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| 09:50 || 79.4 || 1-9, 11-13 || Reference calibration successful; Ant7 (Bands<20); written to SQL (10:19 UT).
|-
| --:-- || -- || -- | Unsuccessful Phase calibration; Due to high winds.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 04 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| 04:13 (04/05)|| 59.7 || 1-9, 11-13 || Reference calibration successful; Ant7 (Bands<20); written to SQL (14:00 UT).
|-
| --:-- || -- || -- | Unsuccessful Phase calibration; Due to high winds.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 05 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| 09:42 || 79.4 || 1-9, 11-13 || Reference calibration successful; Ant7 (Bands<22); written to SQL (10:07 UT).
|-
| 15:14 || 15.7 || 1-9, 11-13 || Phase calibration successful; written to SQL.
|-
| 19:54 || 15.7 || 1-9, 11-13 || Phase calibration successful; written to SQL.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 06 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| 09:38 || 79.1 || 1-9, 11-13 || Reference calibration successful; Ant7 (Bands<27); written to SQL (10:03 UT).
|-
| 19:54 || 15.7 || 1-9, 11-13 || Phase calibration successful; written to SQL.
|-
| 23:14 || 15.7 || 1-9, 11-13 || Phase calibration successful; written to SQL.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 07 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; High solar winds.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; High solar winds.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 08 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; High solar winds.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; High solar winds.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 09 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; High solar winds.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; High solar winds.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 10 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 2 C-class flares observed by EOVSA at 16:44 and 19:45 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 11 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 1 C-class flare observed by EOVSA at 23:45 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 12 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 3 C-class flares observed by EOVSA at 00:41, 15:49 and 17:52 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 13 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 9 || CRIO problems
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 2 C-class flares observed by EOVSA at 14:58 and 21:07 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 14 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 9 || CRIO problems
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 2 C-class flares observed by EOVSA at 22:15 and 23:52 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 15 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 9 || CRIO problems
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 2 M-class and 4 C-class flares observed by EOVSA at 00:05, 01:12, 19:09, 19:30, 20:07 and 20:48 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 16 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 1 M-class flare observed by EOVSA at 17:51 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 17 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 1 M-class and 5 C-class flares observed by EOVSA at 15:47, 16:46, 18:14, 20:08, 22:08 and 23:24 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 18 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 1 M-class and 4 C-class flares observed by EOVSA at 00:58, 01:18, 16:27, 19:17 and 19:42 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 19 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 3 C-class flares observed by EOVSA at 01:10, 15:01 and 18:47 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 20 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 4 C-class flares observed by EOVSA at 01:01, 18:12, 19:09 and 21:55 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 21 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 2 M-class and 1 C-class flares observed by EOVSA at 15:11, 20:51, and 21:48 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 22 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 1 C-class and 4 M-class flares observed by EOVSA at 00:35, 15:15, 15:45, 16:27 and 21:13 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 27 ==
Observer on duty: Dale Gary

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| 16:20 || 70 || 1-6, 8-9, 11-13 || Successful XY Delay calibration. Analysis written to SQL @2024-02-01 13:00.
|-
| 02:20 || 80 || 1-6, 8-9, 11-13 || Successful Reference calibration. Analysis written to SQL @2024-04-27 13:00.
|-
| 16:27 || 30 || 1-6, 8-9, 11-13 || Successful Phase calibration. Analysis written to SQL.
|-
| 19:56 || 14 || 1-6, 8-9, 11-13 || Successful Phase calibration. Analysis written to SQL.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate. 1 M-class flare at 21:30 (during SOLPNTCAL, missed start).

2024 April

2024-04-28T11:38:39Z

Dgary: /* April 27 */

== April 01 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| -- || -- || -- || No Reference calibration; High winds.
|-
| -- || -- || -- || No Phase calibration; High winds.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 02 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| 10:15 || 79.3 || 1-9, 11-13 || Reference calibration successful; Ant7 (Bands<23); written to SQL (10:19 UT).
|-
| 15:54 || 15.7 || 1-6, 8-9, 11-13 || Phase calibration successful; written to SQL.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 03 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| 09:50 || 79.4 || 1-9, 11-13 || Reference calibration successful; Ant7 (Bands<20); written to SQL (10:19 UT).
|-
| --:-- || -- || -- | Unsuccessful Phase calibration; Due to high winds.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 04 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| 04:13 (04/05)|| 59.7 || 1-9, 11-13 || Reference calibration successful; Ant7 (Bands<20); written to SQL (14:00 UT).
|-
| --:-- || -- || -- | Unsuccessful Phase calibration; Due to high winds.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 05 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| 09:42 || 79.4 || 1-9, 11-13 || Reference calibration successful; Ant7 (Bands<22); written to SQL (10:07 UT).
|-
| 15:14 || 15.7 || 1-9, 11-13 || Phase calibration successful; written to SQL.
|-
| 19:54 || 15.7 || 1-9, 11-13 || Phase calibration successful; written to SQL.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 06 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| 09:38 || 79.1 || 1-9, 11-13 || Reference calibration successful; Ant7 (Bands<27); written to SQL (10:03 UT).
|-
| 19:54 || 15.7 || 1-9, 11-13 || Phase calibration successful; written to SQL.
|-
| 23:14 || 15.7 || 1-9, 11-13 || Phase calibration successful; written to SQL.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 07 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; High solar winds.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; High solar winds.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 08 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; High solar winds.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; High solar winds.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 09 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; High solar winds.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; High solar winds.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 10 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 2 C-class flares observed by EOVSA at 16:44 and 19:45 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 11 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 1 C-class flare observed by EOVSA at 23:45 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 12 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 3 C-class flares observed by EOVSA at 00:41, 15:49 and 17:52 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 13 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 9 || CRIO problems
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 2 C-class flares observed by EOVSA at 14:58 and 21:07 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 14 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 9 || CRIO problems
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 2 C-class flares observed by EOVSA at 22:15 and 23:52 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 15 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 9 || CRIO problems
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 2 M-class and 4 C-class flares observed by EOVSA at 00:05, 01:12, 19:09, 19:30, 20:07 and 20:48 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 16 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 1 M-class flare observed by EOVSA at 17:51 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 17 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 1 M-class and 5 C-class flares observed by EOVSA at 15:47, 16:46, 18:14, 20:08, 22:08 and 23:24 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 18 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 1 M-class and 4 C-class flares observed by EOVSA at 00:58, 01:18, 16:27, 19:17 and 19:42 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 19 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 3 C-class flares observed by EOVSA at 01:10, 15:01 and 18:47 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 20 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 4 C-class flares observed by EOVSA at 01:01, 18:12, 19:09 and 21:55 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 21 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 2 M-class and 1 C-class flares observed by EOVSA at 15:11, 20:51, and 21:48 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 22 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 1 C-class and 4 M-class flares observed by EOVSA at 00:35, 15:15, 15:45, 16:27 and 21:13 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 27 ==
Observer on duty: Dale Gary

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| 16:20 || 70 || 1-6, 8-9, 11-13 || Successful XY Delay calibration. Analysis written to SQL @2024-02-01 13:00.
|-
| 02:20 || 80 || 1-6, 8-9, 11-13 || Successful Reference calibration. Analysis written to SQL @2024-04-27 13:00.
|-
| 16:27 || 30 || 1-6, 8-9, 11-13 || Successful Phase calibration. Analysis written to SQL.
|-
| 19:56 || 14 || 1-6, 8-9, 11-13 || Successful Phase calibration. Analysis written to SQL.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate. 1 C-class and 4 M-class flares observed by EOVSA at 00:35, 15:15, 15:45, 16:27 and 21:13 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

2024 April

2024-04-28T11:38:20Z

Dgary: /* April 22 */

== April 01 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| -- || -- || -- || No Reference calibration; High winds.
|-
| -- || -- || -- || No Phase calibration; High winds.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 02 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| 10:15 || 79.3 || 1-9, 11-13 || Reference calibration successful; Ant7 (Bands<23); written to SQL (10:19 UT).
|-
| 15:54 || 15.7 || 1-6, 8-9, 11-13 || Phase calibration successful; written to SQL.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 03 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| 09:50 || 79.4 || 1-9, 11-13 || Reference calibration successful; Ant7 (Bands<20); written to SQL (10:19 UT).
|-
| --:-- || -- || -- | Unsuccessful Phase calibration; Due to high winds.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 04 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| 04:13 (04/05)|| 59.7 || 1-9, 11-13 || Reference calibration successful; Ant7 (Bands<20); written to SQL (14:00 UT).
|-
| --:-- || -- || -- | Unsuccessful Phase calibration; Due to high winds.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 05 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| 09:42 || 79.4 || 1-9, 11-13 || Reference calibration successful; Ant7 (Bands<22); written to SQL (10:07 UT).
|-
| 15:14 || 15.7 || 1-9, 11-13 || Phase calibration successful; written to SQL.
|-
| 19:54 || 15.7 || 1-9, 11-13 || Phase calibration successful; written to SQL.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 06 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| 09:38 || 79.1 || 1-9, 11-13 || Reference calibration successful; Ant7 (Bands<27); written to SQL (10:03 UT).
|-
| 19:54 || 15.7 || 1-9, 11-13 || Phase calibration successful; written to SQL.
|-
| 23:14 || 15.7 || 1-9, 11-13 || Phase calibration successful; written to SQL.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 07 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; High solar winds.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; High solar winds.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 08 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; High solar winds.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; High solar winds.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 09 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; High solar winds.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; High solar winds.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate.

== April 10 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 2 C-class flares observed by EOVSA at 16:44 and 19:45 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 11 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 1 C-class flare observed by EOVSA at 23:45 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 12 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 3 C-class flares observed by EOVSA at 00:41, 15:49 and 17:52 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 13 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 9 || CRIO problems
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 2 C-class flares observed by EOVSA at 14:58 and 21:07 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 14 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 9 || CRIO problems
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 2 C-class flares observed by EOVSA at 22:15 and 23:52 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 15 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 9 || CRIO problems
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 2 M-class and 4 C-class flares observed by EOVSA at 00:05, 01:12, 19:09, 19:30, 20:07 and 20:48 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 16 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 1 M-class flare observed by EOVSA at 17:51 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 17 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 1 M-class and 5 C-class flares observed by EOVSA at 15:47, 16:46, 18:14, 20:08, 22:08 and 23:24 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 18 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 1 M-class and 4 C-class flares observed by EOVSA at 00:58, 01:18, 16:27, 19:17 and 19:42 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 19 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 3 C-class flares observed by EOVSA at 01:10, 15:01 and 18:47 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 20 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 4 C-class flares observed by EOVSA at 01:01, 18:12, 19:09 and 21:55 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 21 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 2 M-class and 1 C-class flares observed by EOVSA at 15:11, 20:51, and 21:48 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 22 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| --:-- || -- || -- || Unsuccessful Reference calibration; 27 m off.
|-
| --:-- || -- || -- || Unsuccessful Phase calibration; 27 m off.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 14 || Cooling system fail.
|-
|}

==== Events ====
Solar activity is moderate. 1 C-class and 4 M-class flares observed by EOVSA at 00:35, 15:15, 15:45, 16:27 and 21:13 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

== April 27 ==
Observer on duty: Caius Selhorst

==== Calibrations ====
{| class="wikitable"
! Start Time (UT) || Duration (min) || Antenna(s) || Comments/Reasons
|-
| 16:20 || 70 || 1-6, 8-9, 11-13 || Successful XY Delay calibration. Analysis written to SQL @2024-02-01 13:00.
|-
| 02:20 || 80 || 1-6, 8-9, 11-13 || Successful Reference calibration. Analysis written to SQL @2024-04-27 13:00.
|-
| 16:27 || 30 || 1-6, 8-9, 11-13 || Successful Phase calibration. Analysis written to SQL.
|-
| 19:56 || 14 || 1-6, 8-9, 11-13 || Successful Phase calibration. Analysis written to SQL.
|-
|}

==== Outages ====
{| class="wikitable"
! Start Time (UT) || End Time (UT) || Antenna(s) || Comments/Reasons
|-
| 00:00 || 23:59 || 7 || It has no VPOL power probably due to a failed optical link
|-
| 00:00 || 23:59 || 10 || It has no VPOL power probably due to a failed optical link
|-
|}

==== Events ====
Solar activity is moderate. 1 C-class and 4 M-class flares observed by EOVSA at 00:35, 15:15, 15:45, 16:27 and 21:13 UT. See dynamic spectra at [http://ovsa.njit.edu/wiki/index.php/2024#April this link].

2.1-m Antennas

2024-04-03T12:49:18Z

Dgary: /* Pointing in the Era of RF Spin Feeds */

=Az-El Mount 2.1 m Dishes=

==Testing RF Spin Feed==
On 2023 Mar 12 we are testing a new feed using antenna 3. This feed is manufactured by RF Spin, and is a Quad-Ridge Flared-Horn (QRFH) feed. This dual-polarization feed is rated for 1-18 GHz, but the beam gets quite narrow at higher frequencies, so we can expect under-illumination at the higher frequencies.

===Pointing/Focus Procedure===
Today is the first test of the feed on an antenna, so our procedure will be to first mount the feed (orientation is 90-degrees uncertain, but that can be determined by cross-correlation with other dishes), then do a SOLPNTCAL to check pointing, update the pointing (possibly for several iterations), then attempt to adjust focus. At the end of that procedure, we should have a good idea of the pointing performance vs. frequency. I am hoping to find that the pointing (primary beam) is very stable and uniform over frequency.

The feed has been mounted and both a GAINCAL and SOLPNTCAL have been done. It seems we also need a SKYCAL although I thought the code would allow that to be missing. I'll try to fix this later, but for now I also ran a SKYCAL. The calibration now completes.

[[File:Explanation_Fig.png|thumb|400px|Explanation for apparently strange measurements. (a) When near the meridian, and RA/Dec sweep is aligned 45 degrees from the E-plane of the feeds so both sweeps and both feeds give similar beam sizes. (b) When well past the meridian, the RA/Dec axes are tilted relative to the AzEl-mounted feeds, so the RA sweep gives a narrow X beam and a wide Y beam while the Dec sweep gives the opposite behavior.]]

'''1.''' The result of the first observation, filename IDB20230312165723, is that the beamwidth is very broad, around twice the nominal primary beamwidth. This might be due to being way out of focus, or it may be the under-illumination. We have now moved the feed about 1" (2.5 cm) farther from the dish.
<gallery mode="nolines">
File:RFSpin_test1_X_165724.png|thumb|100px|Test 1 X_polarization beam size for ants 1-4.
File:RFSpin_test1_Y_165724.png|thumb|100px|Test 1 Y_polarization beam size for ants 1-4.
File:RFSpin_test1_Xoffset_165724.png|thumb|400px|Test 1 X_polarization pointing offset for ant 3.
File:RFSpin_test1_Yoffset_165724.png|thumb|400px|Test 1 Y_polarization pointing offset for ant 3.
File:RFSpin_test1_XYcalfac_165724.png|thumb|100px|Test 1 Cal factor plot for ants 1-4.
</gallery>

'''2.''' The result of the second observation, filename IDB20230312200219, is that the beamwidth is much closer to nominal (!), but strangely the pointing behavior is different for the X feed than for the Y feed. But I'll try moving the feed another 0.5" (1.25 cm) farther and see what happens.
<gallery mode="nolines">
File:RFSpin_test2_X_200220.png|thumb|100px|Test 2 X_polarization beam size for ants 1-4.
File:RFSpin_test2_Y_200220.png|thumb|100px|Test 2 Y_polarization beam size for ants 1-4.
File:RFSpin_test2_Xoffset_200220.png|thumb|400px|Test 2 X_polarization pointing offset for ant 3.
File:RFSpin_test2_Yoffset_200220.png|thumb|400px|Test 2 Y_polarization pointing offset for ant 3.
File:RFSpin_test2_XYcalfac_200220.png|thumb|100px|Test 2 Cal factor plot for ants 1-4.
</gallery>

'''3.''' The result of the third observation, filename IDB20230312205319, is that the beamwidth in one axis is broad again, so things seem to have gotten worse relative to the second observation. I am going to try to split the difference between the first two, i.e. move the feed 0.75" toward the dish relative to its current position.
<gallery mode="nolines">
File:RFSpin_test3_X_205320.png|thumb|100px|Test 3 X_polarization beam size for ants 1-4.
File:RFSpin_test3_Y_205320.png|thumb|100px|Test 3 Y_polarization beam size for ants 1-4.
File:RFSpin_test3_Xoffset_205320.png|thumb|400px|Test 3 X_polarization pointing offset for ant 3.
File:RFSpin_test3_Yoffset_205320.png|thumb|400px|Test 3 Y_polarization pointing offset for ant 3.
File:RFSpin_test3_XYcalfac_205320.png|thumb|100px|Test 3 Cal factor plot for ants 1-4.
</gallery>

'''4.''' The result of the fourth observation, filename IDB20230312213919, is worse in beamwidth on some axes, so I will go back away from the dish again. I got a bit lost in positioning the feed. I think it will be a bit farther out from the dish than the 1" position, so intermediate between 1" and 1.5".
<gallery mode="nolines">
File:RFSpin_test4_X_213920.png|thumb|100px|Test 4 X_polarization beam size for ants 1-4.
File:RFSpin_test4_Y_213920.png|thumb|100px|Test 4 Y_polarization beam size for ants 1-4.
File:RFSpin_test4_Xoffset_213920.png|thumb|400px|Test 4 X_polarization pointing offset for ant 3.
File:RFSpin_test4_Yoffset_213920.png|thumb|400px|Test 4 Y_polarization pointing offset for ant 3.
File:RFSpin_test4_XYcalfac_213920.png|thumb|100px|Test 4 Cal factor plot for ants 1-4.
</gallery>

'''5.''' The result of the fifth observation, filename IDB20230312222119, is still a large beamwidth on some axes. It is not clear to me what might be the cause of this. The gaussian fits look good, but the widths are clearly varying a lot on X feed RA and Y feed Dec. The sizes for the other axes are much narrower and very steady.
<gallery mode="nolines">
File:RFSpin_test5_X_222120.png|thumb|100px|Test 5 X_polarization beam size for ants 1-4.
File:RFSpin_test5_Y_222120.png|thumb|100px|Test 5 Y_polarization beam size for ants 1-4.
File:RFSpin_test5_Xoffset_222120.png|thumb|400px|Test 5 X_polarization pointing offset for ant 3.
File:RFSpin_test5_Yoffset_222120.png|thumb|400px|Test 5 Y_polarization pointing offset for ant 3.
File:RFSpin_test5_XYcalfac_222120.png|thumb|100px|Test 5 Cal factor plot for ants 1-4.
</gallery>

===2023 Mar 13 Focus Tests===
We have figured out that the weirdness of the previous tests was that we were doing an RA-Dec cross pattern but the feeds are moving on an AzEl mount, so their orientation was changing for each test relative to the search pattern. This is coupled with a VERY different beam size in the parallel and cross orientations, so the axis that was affected most kept moving. I have arranged to do the cross pattern in AzEl, and now we are consistently getting the same beam size for both feeds, and it should not change with time. So I am hopeful that a new focus search will give more consistent and comparable results.

We are doing a new series of tests where the focus distance will start at the position farthest from the dish and move in (toward the dish, so farther out on the studs) 1 cm at a time. Rather than doing the analysis between tests, which is quite time consuming, we will just do all of the tests at once, one after another, and I'll do the analysis afterwards.

[[File:RFSpin_bsize_20230313.png|800px|left|'''Beamsize Test Results:''' ''top:'' X beamsize in Az direction vs. focus distance. ''row 2:'' X beamsize in El direction. ''row 3:'' Y beamsize in Az direction. ''bottom:'' Y beamsize in El direction. The nominal beam size for a 2.1-m dish is the orange curve in each plot. Note the search bounds are set not to exceed twice nominal).]]

[[File:RFSpin_offsets_20230313.png|800px|left|'''Pointing Offset Test Results:''' ''top:'' X offsets in Az direction vs. focus distance. ''row 2:'' X offsets in El direction. ''row 3:'' Y offsets in Az direction. ''bottom:'' Y offsets in El direction. The solar disk size is +/- 0.25 degree.]]

Test 1: 20:24:57 77 cm from dish

Test 2: 20:40:59 76 cm from dish

Test 3: 20:59:13 75 cm from dish

Test 4: 21:10:11 74 cm from dish

Test 5: 21:21:16 73 cm from dish

Test 6: 21:33:01 72 cm from dish

Test 7: 21:44:31 71 cm from dish

Test 8: 21:56:25 70 cm from dish

Test 9: 22:07:11 69 cm from dish

Test 10: 22:18:21 68 cm from dish

Test 11: 22:30:39 67 cm from dish

Test 12: 22:43:11 66 cm from dish

Test 13: 23:04:55 65 cm from dish

Test 14: 23:18:16 64 cm from dish

'''Results:''' The results are shown in the two figures above and are quite regular and understandable. The best focus is clearly around 69 cm from the dish, with the beamsize being larger than nominal in both axes. However, the earlier tests clearly show that the E-plane feed beamwidth is larger on the dish (illuminates more of the dish), and hence smaller on the sky, so the beamsize in that direction is more or less nominal. The B-plane feed beamwidth is smaller on the dish (illuminates only the central part of the dish), and hence nearly twice as large as the nominal size on the sky.

===Phase Calibration===
Once the best pointing and focus have been found, we will observe a calibrator and check the delays. I tried this on 2023 Mar 12 when the focus was not correctly set, in the file IDB20230312224929. This resulted in an "okay" delay without modification, which is interesting. However, when I plotted the Ant 14 - Ant 3 phase it was not flat with frequency, but showed the characteristic U shape indicating a change in feed phase center vs. frequency. The U was much less pronounced than that of the Tecom feeds relative to the 27-m feed horns, so presumably the feed phase center has less of a meander than the Tecom feeds. This exercise needs to be repeated, but is postponed until tomorrow (2023 Mar 15) due to rain today.

===2023 Jul 22 Tests of Feed with Radome===
On 21 July, Owen got our new radome-equipped feed mounted on Ant 11, so I spent 21 and 22 July working on pointing and delays. The feed seems to be performing nominally, with the expected oval-shaped beam that is twice as wide in the B plane (because the feed pattern is twice as narrow, which under-illuminates the dish). Since Ant 11 is an equatorial mount, it is not necessary to use the Az-El sweep pattern to measure the beam size. Below are the results after adjusting the pointing. Note that this measurement indicates that the feed is rotated 45 degrees from what it should be, showing the maximally different beam sizes for orthogonal directions of a + pattern instead of the roughly equal responses expected of an X pattern.
<gallery mode="nolines">
File:20230722-Xfeed-beamsize.png | thumb | 400px |
File:20230722-Yfeed-beamsize.png | thumb | 400px |
</gallery>

==Pointing in the Era of RF Spin Feeds==
We have purchased 13 RF Spin feeds equipped with radome. These feeds are to replace the many burnt feeds, and we will fit out the entire array with them. However, their elongated feed pattern is causing problems with determining optimum pointing using our current scheme, and so they require a new method of pointing calibration. The problem stems from the fact that the feed pattern center (x direction, say) shifts as the other (y coordinate) changes, so determining a center from a simple RA-Dec cross pattern doesn't work. As a check, I performed a grid of off-point measurements that demonstrates the highly elliptical feed pattern as shown below for the feed on Ant 11.
<gallery mode="nolines">
File:20231013-Xfeed-beampattern.png | thumb | 400px |
File:20231013-Yfeed-beampattern.png | thumb | 400px |
</gallery>

A better way to do the search is to rotate the cross pattern to align with the feed axes (which are in an X shape relative to their coordinate axes) as shown in the figure at right.
[[File:Explanation_Fig2.png|thumb|150px|New Pointing Search Pattern. Sweeping in this way means that the center of the pattern in one dimension remains in the same place as the offset in the other dimension changes. This will also provide a stable measurement of the beam widths in the two orthogonal directions for each polarization.]]
The problem is that this alignment needs to be done with offsets in RA-Dec for the equatorial dishes and in Az-El for the AzEl dishes. Also, the analysis of the data becomes a bit more complicated. But since this is obviously the right thing to do, I will proceed with the idea. Taking the data will be easy enough using the already established means of creating offsets in a trajectory file, sending it to the Az-El dishes via a file with a .azel extension, and to the equatorial dishes via a file with a .radec extension. However, the Az coordinates should be increased by Az/cos(El), and the RA coordinates should be increased by RA/cos(Dec), so these would have to be calculated for the date/time in question. That means writing a routine to create the files on the fly. The analysis is not that different from what I do now, but with a few important changes such as calculating the vector offset length and keeping track of the fact that RA and Az offsets have opposite signs!

For specificity, note that the X pattern is done starting with offsets in (-Az, +Dec), sweeping to (+Az, -Dec), then starting with (+Az, +Dec), sweeping to (-Az, -Dec). For the older antennas, the -Az corresponds to +RA and vice versa, i.e. (+RA, +Dec) to (-RA, -Dec), etc., so that the patterns are identical at the meridian. The magnitude of the offsets is 10, 5, 2, 1, 0.5, 0.2, 0.1, 0, -0.1, -0.2, -0.5, -1, -2, -5 degrees for each sweep.

==More Focus Tests (2023-Dec-05)==
antenna focus posn start time
ANT 4 11.5 cm 18:15 UT
ANT 4 8.5 cm 20:26 UT
ANT 4 9.5 cm 20:38 UT
ANT 4 10.5 cm 20:50 UT
ANT 4 12.5 cm 21:03 UT
ANT 4 13.5 cm 21:18 UT
ANT 4 14.5 cm 21:34 UT

<gallery mode="nolines">
File:dist85.png|thumb|100px|Focus position 8.5cm
File:dist95.png|thumb|100px|Focus position 9.5cm
File:dist105.png|thumb|100px|Focus position 10.5cm
File:dist115.png|thumb|100px|Focus position 11.5cm
File:dist125.png|thumb|100px|Focus position 12.5cm
File:dist135.png|thumb|100px|Focus position 13.5cm
File:dist145.png|thumb|100px|Focus position 14.5cm
</gallery>

=Equatorial Mount 2.1 m Dishes=
EOVSA comprises 8 newer azimuth-elevation-mounted 2.1 m dishes (plus currently a 9th one, the South Pole dish), and 5 older equatorial-mounted 2.1 m dishes. This document describes some of the important differences for these older dishes.
===Parallactic angle===
The equatorial mounts were outfitted with the same reflector as used for the newer dishes, so that they function in the same way, except that their feeds are fixed in orientation on the sky while the feeds on the newer azel dishes rotate due to the parallactic angle. This angle is computed by the schedule (in stateframe.py), for the current pointing coordinates of each antenna, and inserted into the stateframe as Sche_Data_Chi (SQL naming convention), or sf[‘Schedule’][‘Data’][‘Chi’] (python naming convention), defined as the angle of the azel dish feed relative to an equatorial mount. It should be noted that it is calculated for all antennas, independent of whether the dish is an azel or equatorial mount. For a given azimuth and elevation, the paralactic angle is computed from
<center><math>\chi=\arctan 2(-\cos\lambda \sin a , \sin\lambda \cos e- \cos \lambda \sin e\cos a ) </math></center>

where <math> \lambda</math> = latitude (37.233170 degrees for OVRO), <math>a</math> = azimuth, and <math>e</math> = elevation. The arctan2 function resolves the 180-degree ambiguity. Note that any baseline involving two dissimilar dishes, the phase will rotate according to the parallactic angle, and will need to be corrected by the DPP prior to writing to the Miriad database. The default phase will be that of the azel dishes—that is, baselines with one azel and one equatorial dish will be phase-corrected to correspond to the phase as measured by two azel dishes. [This statement will need to be tested, and possibly amended if it is not correct.]

===Pointing of the equatorial-mount dishes—step size===
The equatorially-mounted dishes have a step-motor drive system, consisting of a motor of ''s'' = 200 steps/revolution, followed by a harmonic drive (a complication is that we have two DIFFERENT harmonic ratios in use, three dishes with ''h'' = 100:1 and two with ''h'' = 160:1). These motors drive a 20-tooth sprocket gear and meshes with a chain having the equivalent of 225 “teeth” in one revolution, for a further reduction ''r'' = 225:20. In addition, we are running the motors with a 16:1 microstepping ratio (<math>\mu</math>), which means that 16 microsteps are needed for one motor step. It is these microsteps that are counted by the system. The resulting of microsteps/degree, then, is
<center><math>n=\mu shr/360 </math></center>
This makes a nice round number, ''n'' = 10000 steps/degree for ''h'' = 100:1, and ''n'' = 16000 steps/degree for ''h'' = 160:1. Currently, Ants 9, 11 and 13 have 10000 steps/degree, while Ants 10, and ultimately 12 will have 16000 steps/degree. These values are given in the crio.ini file.
Obviously, these are nominal values, and the true step size could be slightly different. The step size needs to be part of the pointing parameter solution.

===Pointing of the equatorial-mount dishes—restricted sky coverage===
The equatorial-mount dishes have a restricted sky coverage relative to the azel dishes, given in terms of hour angle limits and declication limits. The precise limits (prior to any pointing corrections) can be determined by adjusting the “hard limits” (limit switches) to trigger just before the antenna hits the stops, and reading the angles at those stopped points. In order to achieve the greatest sky coverage, the hard limits should be set as close as possible to the stops, but with due regard for possible collisions of cables and other obstructions by the mount. In particular, the thick conduit on the north side of the mounts can interfere with the counter-weights when close to the stops, so the limit switches must be set somewhat away from the stops to allow the counter-weights to clear. This has been done with some care on antennas 9 and 10, with the following results (by way of example). The “soft limits” are then selected to stop the motion programmatically just before the limit switch would trigger. It is very important that the motors never reach the hard stops, since that causes the motor to stall while still counting, and hence the step count is compromised. The pointing is only good if the step count is known.
{| class="wikitable"
!Axis
!Ant 9 Hard Limit
!Ant 9 Soft Limit
!Ant 10 Hard Limit
!Ant 10 Soft Limit
|-
| HA Low
| -59.81
| -59.5
| -58.7
| -58.0
|-
| HA High
| +58.33
| +58.0
| +59.3
| +59.0
|-
| Dec Low
| -24.28
| -24.0
| -24.27
| -24.0
|-
| Dec Hi
| +45.43
| +45.0
| +46.25
| +46.0
|-
|}

One concern is that, once the pointing coefficients (and step size) are determined, the angular positions shift somewhat. It would be better to have these hard- and soft-limits not change just because of pointing coefficient adjustments. This will require some thought.
One consequence of this restricted sky coverage is that there will be times (especially in the summer) when some of the dishes cannot reach the Sun or calibrator. With the current set up, when a position is requested that cannot be reached by a dish, it will go as close to the position as possible and then just wait there. The position error can be used to determine which dishes are not tracking. For calibration, all calibrator sources will need to be chosen to respect the equatorial dishes, however, since the 27-m antennas also have this same sky coverage limitation. Therefore, the schedule, which chooses the “best” calibrator automatically, must be set to use the above sky coverage limitation.
Another, rather serious consequence of the restricted sky coverage is that the SOLPNTCAL procedure, which currently runs twice per day, works by off-pointing the dishes by +/- 5 degrees from the Sun in both RA and Dec. Since the south limit of the dishes is only -24 degrees, the dishes will not be able to reach -5 degrees from Sun center whenever the Sun is below declination -19 degrees. This is a date range of roughly Nov 18-Jan 25! During this period, the equatorial-mount dishes will not be able to do a SOLPNTCAL. It could be possible to somehow adjust the procedure to allow some sort of analysis (full HA and half of Dec, for example).

===Pointing of the equatorial-mount dishes—star pointing===
I made an attempt to observe stars with Ant 9, but was not happy with the constant vibrations, which cause the stars to be linear rather than round. I discussed it with Kjell, and he had a new mount for the telescope made (Figure 1), which will go in place of the feed package. With luck, this should allow for much less vibrational motion and hence result in much better star images. I plan to do a first test on Ant 9 tonight.
[[File: new_ telescope_mount.png|thumb|600px|Figure 1: The new mount for the optical telescope, to be put in place of the radio front-end receiver. This should greatly reduce vibrations that lead to non-circular stars.]]

In addition, I updated the startracktable() routine in readbsc.py to account for the reduced sky coverage of the equatorial-mount dishes, since my earlier attempt did not do this, and the antenna spent a lot of time at the limits.

= Debugging =
Ant 12 (the SPASRT antenna) may need its turn count adjusted. To do this, connect to its web page and change parameter 20.16. If its current turn count is 2, set it to 1 and reboot. If it is currently 1, set it to 2 and reboot.

2.1-m Antennas

2024-04-03T12:47:58Z

Dgary: /* Pointing in the Era of RF Spin Feeds */

=Az-El Mount 2.1 m Dishes=

==Testing RF Spin Feed==
On 2023 Mar 12 we are testing a new feed using antenna 3. This feed is manufactured by RF Spin, and is a Quad-Ridge Flared-Horn (QRFH) feed. This dual-polarization feed is rated for 1-18 GHz, but the beam gets quite narrow at higher frequencies, so we can expect under-illumination at the higher frequencies.

===Pointing/Focus Procedure===
Today is the first test of the feed on an antenna, so our procedure will be to first mount the feed (orientation is 90-degrees uncertain, but that can be determined by cross-correlation with other dishes), then do a SOLPNTCAL to check pointing, update the pointing (possibly for several iterations), then attempt to adjust focus. At the end of that procedure, we should have a good idea of the pointing performance vs. frequency. I am hoping to find that the pointing (primary beam) is very stable and uniform over frequency.

The feed has been mounted and both a GAINCAL and SOLPNTCAL have been done. It seems we also need a SKYCAL although I thought the code would allow that to be missing. I'll try to fix this later, but for now I also ran a SKYCAL. The calibration now completes.

[[File:Explanation_Fig.png|thumb|400px|Explanation for apparently strange measurements. (a) When near the meridian, and RA/Dec sweep is aligned 45 degrees from the E-plane of the feeds so both sweeps and both feeds give similar beam sizes. (b) When well past the meridian, the RA/Dec axes are tilted relative to the AzEl-mounted feeds, so the RA sweep gives a narrow X beam and a wide Y beam while the Dec sweep gives the opposite behavior.]]

'''1.''' The result of the first observation, filename IDB20230312165723, is that the beamwidth is very broad, around twice the nominal primary beamwidth. This might be due to being way out of focus, or it may be the under-illumination. We have now moved the feed about 1" (2.5 cm) farther from the dish.
<gallery mode="nolines">
File:RFSpin_test1_X_165724.png|thumb|100px|Test 1 X_polarization beam size for ants 1-4.
File:RFSpin_test1_Y_165724.png|thumb|100px|Test 1 Y_polarization beam size for ants 1-4.
File:RFSpin_test1_Xoffset_165724.png|thumb|400px|Test 1 X_polarization pointing offset for ant 3.
File:RFSpin_test1_Yoffset_165724.png|thumb|400px|Test 1 Y_polarization pointing offset for ant 3.
File:RFSpin_test1_XYcalfac_165724.png|thumb|100px|Test 1 Cal factor plot for ants 1-4.
</gallery>

'''2.''' The result of the second observation, filename IDB20230312200219, is that the beamwidth is much closer to nominal (!), but strangely the pointing behavior is different for the X feed than for the Y feed. But I'll try moving the feed another 0.5" (1.25 cm) farther and see what happens.
<gallery mode="nolines">
File:RFSpin_test2_X_200220.png|thumb|100px|Test 2 X_polarization beam size for ants 1-4.
File:RFSpin_test2_Y_200220.png|thumb|100px|Test 2 Y_polarization beam size for ants 1-4.
File:RFSpin_test2_Xoffset_200220.png|thumb|400px|Test 2 X_polarization pointing offset for ant 3.
File:RFSpin_test2_Yoffset_200220.png|thumb|400px|Test 2 Y_polarization pointing offset for ant 3.
File:RFSpin_test2_XYcalfac_200220.png|thumb|100px|Test 2 Cal factor plot for ants 1-4.
</gallery>

'''3.''' The result of the third observation, filename IDB20230312205319, is that the beamwidth in one axis is broad again, so things seem to have gotten worse relative to the second observation. I am going to try to split the difference between the first two, i.e. move the feed 0.75" toward the dish relative to its current position.
<gallery mode="nolines">
File:RFSpin_test3_X_205320.png|thumb|100px|Test 3 X_polarization beam size for ants 1-4.
File:RFSpin_test3_Y_205320.png|thumb|100px|Test 3 Y_polarization beam size for ants 1-4.
File:RFSpin_test3_Xoffset_205320.png|thumb|400px|Test 3 X_polarization pointing offset for ant 3.
File:RFSpin_test3_Yoffset_205320.png|thumb|400px|Test 3 Y_polarization pointing offset for ant 3.
File:RFSpin_test3_XYcalfac_205320.png|thumb|100px|Test 3 Cal factor plot for ants 1-4.
</gallery>

'''4.''' The result of the fourth observation, filename IDB20230312213919, is worse in beamwidth on some axes, so I will go back away from the dish again. I got a bit lost in positioning the feed. I think it will be a bit farther out from the dish than the 1" position, so intermediate between 1" and 1.5".
<gallery mode="nolines">
File:RFSpin_test4_X_213920.png|thumb|100px|Test 4 X_polarization beam size for ants 1-4.
File:RFSpin_test4_Y_213920.png|thumb|100px|Test 4 Y_polarization beam size for ants 1-4.
File:RFSpin_test4_Xoffset_213920.png|thumb|400px|Test 4 X_polarization pointing offset for ant 3.
File:RFSpin_test4_Yoffset_213920.png|thumb|400px|Test 4 Y_polarization pointing offset for ant 3.
File:RFSpin_test4_XYcalfac_213920.png|thumb|100px|Test 4 Cal factor plot for ants 1-4.
</gallery>

'''5.''' The result of the fifth observation, filename IDB20230312222119, is still a large beamwidth on some axes. It is not clear to me what might be the cause of this. The gaussian fits look good, but the widths are clearly varying a lot on X feed RA and Y feed Dec. The sizes for the other axes are much narrower and very steady.
<gallery mode="nolines">
File:RFSpin_test5_X_222120.png|thumb|100px|Test 5 X_polarization beam size for ants 1-4.
File:RFSpin_test5_Y_222120.png|thumb|100px|Test 5 Y_polarization beam size for ants 1-4.
File:RFSpin_test5_Xoffset_222120.png|thumb|400px|Test 5 X_polarization pointing offset for ant 3.
File:RFSpin_test5_Yoffset_222120.png|thumb|400px|Test 5 Y_polarization pointing offset for ant 3.
File:RFSpin_test5_XYcalfac_222120.png|thumb|100px|Test 5 Cal factor plot for ants 1-4.
</gallery>

===2023 Mar 13 Focus Tests===
We have figured out that the weirdness of the previous tests was that we were doing an RA-Dec cross pattern but the feeds are moving on an AzEl mount, so their orientation was changing for each test relative to the search pattern. This is coupled with a VERY different beam size in the parallel and cross orientations, so the axis that was affected most kept moving. I have arranged to do the cross pattern in AzEl, and now we are consistently getting the same beam size for both feeds, and it should not change with time. So I am hopeful that a new focus search will give more consistent and comparable results.

We are doing a new series of tests where the focus distance will start at the position farthest from the dish and move in (toward the dish, so farther out on the studs) 1 cm at a time. Rather than doing the analysis between tests, which is quite time consuming, we will just do all of the tests at once, one after another, and I'll do the analysis afterwards.

[[File:RFSpin_bsize_20230313.png|800px|left|'''Beamsize Test Results:''' ''top:'' X beamsize in Az direction vs. focus distance. ''row 2:'' X beamsize in El direction. ''row 3:'' Y beamsize in Az direction. ''bottom:'' Y beamsize in El direction. The nominal beam size for a 2.1-m dish is the orange curve in each plot. Note the search bounds are set not to exceed twice nominal).]]

[[File:RFSpin_offsets_20230313.png|800px|left|'''Pointing Offset Test Results:''' ''top:'' X offsets in Az direction vs. focus distance. ''row 2:'' X offsets in El direction. ''row 3:'' Y offsets in Az direction. ''bottom:'' Y offsets in El direction. The solar disk size is +/- 0.25 degree.]]

Test 1: 20:24:57 77 cm from dish

Test 2: 20:40:59 76 cm from dish

Test 3: 20:59:13 75 cm from dish

Test 4: 21:10:11 74 cm from dish

Test 5: 21:21:16 73 cm from dish

Test 6: 21:33:01 72 cm from dish

Test 7: 21:44:31 71 cm from dish

Test 8: 21:56:25 70 cm from dish

Test 9: 22:07:11 69 cm from dish

Test 10: 22:18:21 68 cm from dish

Test 11: 22:30:39 67 cm from dish

Test 12: 22:43:11 66 cm from dish

Test 13: 23:04:55 65 cm from dish

Test 14: 23:18:16 64 cm from dish

'''Results:''' The results are shown in the two figures above and are quite regular and understandable. The best focus is clearly around 69 cm from the dish, with the beamsize being larger than nominal in both axes. However, the earlier tests clearly show that the E-plane feed beamwidth is larger on the dish (illuminates more of the dish), and hence smaller on the sky, so the beamsize in that direction is more or less nominal. The B-plane feed beamwidth is smaller on the dish (illuminates only the central part of the dish), and hence nearly twice as large as the nominal size on the sky.

===Phase Calibration===
Once the best pointing and focus have been found, we will observe a calibrator and check the delays. I tried this on 2023 Mar 12 when the focus was not correctly set, in the file IDB20230312224929. This resulted in an "okay" delay without modification, which is interesting. However, when I plotted the Ant 14 - Ant 3 phase it was not flat with frequency, but showed the characteristic U shape indicating a change in feed phase center vs. frequency. The U was much less pronounced than that of the Tecom feeds relative to the 27-m feed horns, so presumably the feed phase center has less of a meander than the Tecom feeds. This exercise needs to be repeated, but is postponed until tomorrow (2023 Mar 15) due to rain today.

===2023 Jul 22 Tests of Feed with Radome===
On 21 July, Owen got our new radome-equipped feed mounted on Ant 11, so I spent 21 and 22 July working on pointing and delays. The feed seems to be performing nominally, with the expected oval-shaped beam that is twice as wide in the B plane (because the feed pattern is twice as narrow, which under-illuminates the dish). Since Ant 11 is an equatorial mount, it is not necessary to use the Az-El sweep pattern to measure the beam size. Below are the results after adjusting the pointing. Note that this measurement indicates that the feed is rotated 45 degrees from what it should be, showing the maximally different beam sizes for orthogonal directions of a + pattern instead of the roughly equal responses expected of an X pattern.
<gallery mode="nolines">
File:20230722-Xfeed-beamsize.png | thumb | 400px |
File:20230722-Yfeed-beamsize.png | thumb | 400px |
</gallery>

==Pointing in the Era of RF Spin Feeds==
We have purchased 13 RF Spin feeds equipped with radome. These feeds are to replace the many burnt feeds, and we will fit out the entire array with them. However, their elongated feed pattern is causing problems with determining optimum pointing using our current scheme, and so they require a new method of pointing calibration. The problem stems from the fact that the feed pattern center (x direction, say) shifts as the other (y coordinate) changes, so determining a center from a simple RA-Dec cross pattern doesn't work. As a check, I performed a grid of off-point measurements that demonstrates the highly elliptical feed pattern as shown below for the feed on Ant 11.
<gallery mode="nolines">
File:20231013-Xfeed-beampattern.png | thumb | 400px |
File:20231013-Yfeed-beampattern.png | thumb | 400px |
</gallery>

A better way to do the search is to rotate the cross pattern to align with the feed axes (which are in an X shape relative to their coordinate axes) as shown in the figure at right.
[[File:Explanation_Fig2.png|thumb|150px|New Pointing Search Pattern. Sweeping in this way means that the center of the pattern in one dimension remains in the same place as the offset in the other dimension changes. This will also provide a stable measurement of the beam widths in the two orthogonal directions for each polarization.]]
The problem is that this alignment needs to be done with offsets in RA-Dec for the equatorial dishes and in Az-El for the AzEl dishes. Also, the analysis of the data becomes a bit more complicated. But since this is obviously the right thing to do, I will proceed with the idea. Taking the data will be easy enough using the already established means of creating offsets in a trajectory file, sending it to the Az-El dishes via a file with a .azel extension, and to the equatorial dishes via a file with a .radec extension. However, the Az coordinates should be increased by Az/cos(El), and the RA coordinates should be increased by RA/cos(Dec), so these would have to be calculated for the date/time in question. That means writing a routine to create the files on the fly. The analysis is not that different from what I do now, but with a few important changes such as calculating the vector offset length and keeping track of the fact that RA and Az offsets have opposite signs!

For specificity, note that the X pattern is done starting with offsets in (-Az, +Dec), sweeping to (+Az, -Dec), then starting with (+Az, +Dec), sweeping to (-Az, -Dec). For the older antennas, the -Az*cos(Dec) corresponds to +RA and vice versa, i.e. (+RA, +Dec) to (-RA, -Dec), etc., so that the patterns are identical at the meridian. The magnitude of the offsets is 10, 5, 2, 1, 0.5, 0.2, 0.1, 0, -0.1, -0.2, -0.5, -1, -2, -5 degrees for each sweep.

==More Focus Tests (2023-Dec-05)==
antenna focus posn start time
ANT 4 11.5 cm 18:15 UT
ANT 4 8.5 cm 20:26 UT
ANT 4 9.5 cm 20:38 UT
ANT 4 10.5 cm 20:50 UT
ANT 4 12.5 cm 21:03 UT
ANT 4 13.5 cm 21:18 UT
ANT 4 14.5 cm 21:34 UT

<gallery mode="nolines">
File:dist85.png|thumb|100px|Focus position 8.5cm
File:dist95.png|thumb|100px|Focus position 9.5cm
File:dist105.png|thumb|100px|Focus position 10.5cm
File:dist115.png|thumb|100px|Focus position 11.5cm
File:dist125.png|thumb|100px|Focus position 12.5cm
File:dist135.png|thumb|100px|Focus position 13.5cm
File:dist145.png|thumb|100px|Focus position 14.5cm
</gallery>

=Equatorial Mount 2.1 m Dishes=
EOVSA comprises 8 newer azimuth-elevation-mounted 2.1 m dishes (plus currently a 9th one, the South Pole dish), and 5 older equatorial-mounted 2.1 m dishes. This document describes some of the important differences for these older dishes.
===Parallactic angle===
The equatorial mounts were outfitted with the same reflector as used for the newer dishes, so that they function in the same way, except that their feeds are fixed in orientation on the sky while the feeds on the newer azel dishes rotate due to the parallactic angle. This angle is computed by the schedule (in stateframe.py), for the current pointing coordinates of each antenna, and inserted into the stateframe as Sche_Data_Chi (SQL naming convention), or sf[‘Schedule’][‘Data’][‘Chi’] (python naming convention), defined as the angle of the azel dish feed relative to an equatorial mount. It should be noted that it is calculated for all antennas, independent of whether the dish is an azel or equatorial mount. For a given azimuth and elevation, the paralactic angle is computed from
<center><math>\chi=\arctan 2(-\cos\lambda \sin a , \sin\lambda \cos e- \cos \lambda \sin e\cos a ) </math></center>

where <math> \lambda</math> = latitude (37.233170 degrees for OVRO), <math>a</math> = azimuth, and <math>e</math> = elevation. The arctan2 function resolves the 180-degree ambiguity. Note that any baseline involving two dissimilar dishes, the phase will rotate according to the parallactic angle, and will need to be corrected by the DPP prior to writing to the Miriad database. The default phase will be that of the azel dishes—that is, baselines with one azel and one equatorial dish will be phase-corrected to correspond to the phase as measured by two azel dishes. [This statement will need to be tested, and possibly amended if it is not correct.]

===Pointing of the equatorial-mount dishes—step size===
The equatorially-mounted dishes have a step-motor drive system, consisting of a motor of ''s'' = 200 steps/revolution, followed by a harmonic drive (a complication is that we have two DIFFERENT harmonic ratios in use, three dishes with ''h'' = 100:1 and two with ''h'' = 160:1). These motors drive a 20-tooth sprocket gear and meshes with a chain having the equivalent of 225 “teeth” in one revolution, for a further reduction ''r'' = 225:20. In addition, we are running the motors with a 16:1 microstepping ratio (<math>\mu</math>), which means that 16 microsteps are needed for one motor step. It is these microsteps that are counted by the system. The resulting of microsteps/degree, then, is
<center><math>n=\mu shr/360 </math></center>
This makes a nice round number, ''n'' = 10000 steps/degree for ''h'' = 100:1, and ''n'' = 16000 steps/degree for ''h'' = 160:1. Currently, Ants 9, 11 and 13 have 10000 steps/degree, while Ants 10, and ultimately 12 will have 16000 steps/degree. These values are given in the crio.ini file.
Obviously, these are nominal values, and the true step size could be slightly different. The step size needs to be part of the pointing parameter solution.

===Pointing of the equatorial-mount dishes—restricted sky coverage===
The equatorial-mount dishes have a restricted sky coverage relative to the azel dishes, given in terms of hour angle limits and declication limits. The precise limits (prior to any pointing corrections) can be determined by adjusting the “hard limits” (limit switches) to trigger just before the antenna hits the stops, and reading the angles at those stopped points. In order to achieve the greatest sky coverage, the hard limits should be set as close as possible to the stops, but with due regard for possible collisions of cables and other obstructions by the mount. In particular, the thick conduit on the north side of the mounts can interfere with the counter-weights when close to the stops, so the limit switches must be set somewhat away from the stops to allow the counter-weights to clear. This has been done with some care on antennas 9 and 10, with the following results (by way of example). The “soft limits” are then selected to stop the motion programmatically just before the limit switch would trigger. It is very important that the motors never reach the hard stops, since that causes the motor to stall while still counting, and hence the step count is compromised. The pointing is only good if the step count is known.
{| class="wikitable"
!Axis
!Ant 9 Hard Limit
!Ant 9 Soft Limit
!Ant 10 Hard Limit
!Ant 10 Soft Limit
|-
| HA Low
| -59.81
| -59.5
| -58.7
| -58.0
|-
| HA High
| +58.33
| +58.0
| +59.3
| +59.0
|-
| Dec Low
| -24.28
| -24.0
| -24.27
| -24.0
|-
| Dec Hi
| +45.43
| +45.0
| +46.25
| +46.0
|-
|}

One concern is that, once the pointing coefficients (and step size) are determined, the angular positions shift somewhat. It would be better to have these hard- and soft-limits not change just because of pointing coefficient adjustments. This will require some thought.
One consequence of this restricted sky coverage is that there will be times (especially in the summer) when some of the dishes cannot reach the Sun or calibrator. With the current set up, when a position is requested that cannot be reached by a dish, it will go as close to the position as possible and then just wait there. The position error can be used to determine which dishes are not tracking. For calibration, all calibrator sources will need to be chosen to respect the equatorial dishes, however, since the 27-m antennas also have this same sky coverage limitation. Therefore, the schedule, which chooses the “best” calibrator automatically, must be set to use the above sky coverage limitation.
Another, rather serious consequence of the restricted sky coverage is that the SOLPNTCAL procedure, which currently runs twice per day, works by off-pointing the dishes by +/- 5 degrees from the Sun in both RA and Dec. Since the south limit of the dishes is only -24 degrees, the dishes will not be able to reach -5 degrees from Sun center whenever the Sun is below declination -19 degrees. This is a date range of roughly Nov 18-Jan 25! During this period, the equatorial-mount dishes will not be able to do a SOLPNTCAL. It could be possible to somehow adjust the procedure to allow some sort of analysis (full HA and half of Dec, for example).

===Pointing of the equatorial-mount dishes—star pointing===
I made an attempt to observe stars with Ant 9, but was not happy with the constant vibrations, which cause the stars to be linear rather than round. I discussed it with Kjell, and he had a new mount for the telescope made (Figure 1), which will go in place of the feed package. With luck, this should allow for much less vibrational motion and hence result in much better star images. I plan to do a first test on Ant 9 tonight.
[[File: new_ telescope_mount.png|thumb|600px|Figure 1: The new mount for the optical telescope, to be put in place of the radio front-end receiver. This should greatly reduce vibrations that lead to non-circular stars.]]

In addition, I updated the startracktable() routine in readbsc.py to account for the reduced sky coverage of the equatorial-mount dishes, since my earlier attempt did not do this, and the antenna spent a lot of time at the limits.

= Debugging =
Ant 12 (the SPASRT antenna) may need its turn count adjusted. To do this, connect to its web page and change parameter 20.16. If its current turn count is 2, set it to 1 and reboot. If it is currently 1, set it to 2 and reboot.

EOVSA Data Products

2024-03-29T18:30:21Z

Dgary: /* Raw "Interim" Database (IDB) visibility data */

=Introduction=
EOVSA observes the full disk of the Sun at all times when the Sun is >10 degrees above the local horizon (season dependent and ranges from 7-12 hours duration centered on 20 UT). EOVSA records data at 451 science frequency channels each second, in four polarization products, as well as additional total flux measurements from each individual antenna. Figure 1 summarizes the different levels of data we produce. The later sections will give a more detailed description and usage examples.
[[File:pipeline_flowchart.jpg|center|600px|EOVSA pipeline block diagram/flow chart ]]

=Level 0 - Raw visibility data from the instrument=

As outlined in Figure 1, EOVSA creates raw data products in the left-hand column (labeled Level 0). This includes observations of cosmic sources for phase calibration, and gain and pointing observations required for total power calibration.

==Raw "Interim" Database (IDB) visibility data==
Full-resolution raw "Interim" Database (IDB) visibility data. They are stored in Miriad format, and hence may not be that useful for most people. Be patient after clicking the link--this is a very long list of directories, one for each available date. Recent data (latest few months) can be retrieved from the following page:

https://www.ovsa.njit.edu/fits/IDB/

For older data, visit the UC/Berkeley hosting page:

https://research.ssl.berkeley.edu/data/eovsa/IDB/

==Raw 1-min-averaged visibility data==
This is the same as for the IDB data, except with 1-minute time integration applied. This is typically not useful for flares, but is perfectly fine for imaging active regions and full Sun. These data can be retrieved from the following page:

http://www.ovsa.njit.edu/fits/UDB/

=Level 0.5 - Calibrated visibility data=
After applying calibration and other preliminary processing to the raw (level 0) data, we create the CASA ms’s in the second column in Figure 1 (labeled "level 0.5"). These visibility data are in the Fourier domain of the true images in the plane of the sky and are not immediately ready for spectral imaging analysis yet. However, they have all of the required content to produce images and spectrogram data in standard FITS format (level 1.0). We provide a set of standard ms’s for each day (red boxes in Figure 1), for use by researchers who know how to deal with visibility data. These data are more suitable for experienced users to exploit the full potential of EOVSA data, such as spatially resolved spectral analysis. Processing these data requires CASA or sunCASA (https://github.com/suncasa/suncasa-src). Please refer to our tutorial at [[EOVSA_Data_Analysis_Tutorial]].

==Calibrated full-resolution visibility data for flare events==
Calibrated and self-calibrated visibility data for flare events (purple boxes in Figure 1) will typically be available within 7 days after they are taken. They will be released at our flare list site soon: https://ovsa.njit.edu/flarelist

==Self-calibrated 1-min-averaged visibility data==
EOVSA 1-min averaged visibility data in CASA ms format can be retrieved from the following page:

http://www.ovsa.njit.edu/fits/UDBms_slfcaled

=Level 1.0 - Images and spectrogram data in standard FITS format =

Level 1.0 data are for users who prefer to work with spectrogram (frequency-time) and image data directly, which are also outputs of the pipeline system shown in Figure 1 (orange boxes). They are perfectly suitable to be used as context data for comparison with other multi-wavelength observations but are not (yet) intended for quantitative spatially resolved spectral analysis.

Spectrograms are provided as standard FITS tables containing the frequency list, list of times, and data in both total power (TP) and a sum of amplitudes over intermediate-length baselines (cross power or XP). Likewise, image data products are in FITS format with standard keywords and are converted into the Helioprojective Cartesian coordinate system compatible with the World Coordinate System (WCS) convention, along with correct registration for the spatial, spectral, and temporal coordinates. Both the spectrogram and image data products are calibrated and have physical radio intensity units (sfu for spectrograms and brightness temperature for radio images).

We provide the following level 1 data products:
* Synoptic products:
** '''All-day spectrograms''':
** '''All-day synoptic images''': Full disk images at 6 selected frequency bands centered at 1.4, 3.0, 4.5, 6.8, 10.2, and 13.9 GHz are produced once per day utilizing the earth-rotation synthesis, calibrated in brightness temperature. This is because EOVSA has a limited number of baselines and we need a long integration to fill up the uv domain in order to make full-disk images.
* Event-based products:
** '''Flare spectrograms''': These are full time and frequency resolution spectrograms produced from the median of calibrated cross-power visibilities in FITS format, cropped to cover the flare duration. Preflare background is also subtracted. Compared to total-power spectrograms, these spectrograms have the advantage of revealing details of the flare evolution by "filtering out" the large-scale, continuous background from the visibilities. Note that for certain flares that have a large source size, the flux can be lower than its true values (as a fraction of the flux will be "resolved out").
** '''Pipeline-produced spectral images''': We also have a semi-automated flare imaging pipeline to produce calibrated (and self-calibrated) images at 12-s cadence at up to 10 frequency bands. They are saved in standard FITS format and have been registered into Helioprojective coordinates. They can be read by SSWIDL or astropy/sunpy. These data have already been calibrated to physical units and are usually good to be compared with context data. But please be cautious when using them for quantitative spectral analysis.

{| class="wikitable"
|+ Summary of EOVSA Level 1 Data Products
|-
! scope="col"| Category
! scope="col"| Data Product
! scope="col"| Naming Convention
! scope="col"| Download Link
|-
! rowspan="2" | Synoptic Spectrograms
| All-day TP Spectrograms
| EOVSA_TPall_yyyymmdd.fts
!rowspan="9" | https://ovsa.njit.edu/browser
|-
| All-day XP Spectrograms
| EOVSA_XPall_yyyymmdd.fts
|-
! rowspan="7" | Synoptic Images
|-
| Synoptic 1.4 GHz images
| eovsa_yyyymmdd.spw00-01.tb.disk.fits
|-
| Synoptic 3.0 GHz images
| eovsa_yyyymmdd.spw02-05.tb.disk.fits
|-
| Synoptic 4.5 GHz images
| eovsa_yyyymmdd.spw06-10.tb.disk.fits
|-
| Synoptic 6.8 GHz images
| eovsa_yyyymmdd.spw11-20.tb.disk.fits
|-
| Synoptic 10.2 GHz images
| eovsa_yyyymmdd.spw21-30.tb.disk.fits
|-
| Synoptic 13.9 GHz images
| eovsa_yyyymmdd.spw31-43.tb.disk.fits
|-
! rowspan="1" | Flare Spectrograms
| Full-resolution cross-power Spectrogram
| eovsa.spec.flare_id_YYYYMMDDHHMMSS.fits
!rowspan="2" | https://ovsa.njit.edu/flarelist
|-
! rowspan="1" | Flare Spectral Images
| Pipeline-produced spectral images
| eovsa.lev1_mbd_12s.YYYY-MM-DDTHHMMSSZ.image.fits
|-
|}

==Browsing and Downloading level 1 data==
[[File:eovsa_browser.jpg|right|thumb|EOVSA Browser]]
[[file:EOVSA_flarelist.jpg|right|thumb|EOVSA Flare List]]
===Synoptic level 1 data===
EOVSA Level 1 synoptic data products can be retrieved with the following steps:
* Go to [http://ovsa.njit.edu/browser/ EOVSA browser] page.
* Browse to the date of interest.
* Click "synoptic fits" button next to the calendar tool.
* Select the data product based on the names listed in the table above.

===Flare level 1 data===
EOVSA flare list with spectrograms and spectral images can be queried and downloaded at https://ovsa.njit.edu/flarelist. Users can use the top box to select a time range of interest and query our flare list. The results are displayed in the dropdown box. An interactive plot of the flare light curves will be shown at the bottom of the page once an event is highlighted (by clicking on the flare ID). Quicklook plots and FITS files of the spectrograms and flare movies can be accessed by clicking the icons in each flare record.

==Reading and Using level 1 data==
===Introduction===
All our level 1 data products are in FITS format. All the images have standard, WCS-compatible coordinates. Users can use their favorite method to read these files. In the following, we provide minimal examples to read them with Astropy and Sunpy.

===Event-Based Data Products===
* An example of how to read and plot the flare spectrograms and images in Python (with Astropy and SunPy) can be accessed at [https://colab.research.google.com/drive/1Y3ONWCxLPYvWda5_LqFNxafJtwZDNJBD?usp=sharing#scrollTo=ueiMoHbdxfo- this Google Colab Jupyter notebook].
* We are working on an example with SSWIDL and will release it soon.

===Synoptic Data Products===

====All-day Spectrograms====
To read a spectrogram file in Python using the suncasa library:

<pre style="background-color: #FCEBD9;">
from suncasa.eovsa import eovsa_dspec as ds
from astropy.time import Time
from matplotlib.colors import LogNorm
## Read EOVSA Dynamic Spectrum FITS file <filename>
filename = 'EOVSA_TPall_20170713.fts'
s = ds.get_dspec(filename, doplot=True, cmap='gist_heat', norm=LogNorm(vmax=2.1e3, vmin=40))
## To access the data in the spectrogram object, use
spec = s['spectrogram'] ## (Array of amplitudes in SFU, of size nfreq,ntimes)
fghz = s['spectrum_axis'] ## (Array of frequencies in GHz, of size nfreq)
tim = Time(s['time_axis'], format='mjd') ## (Array of UT times in astropy.time object, of size ntimes)

</pre>

The '''get_dspec''' function is accessible on [https://github.com/suncasa/suncasa-src/blob/master/suncasa/eovsa/eovsa_dspec.py GitHub]. For comprehensive guidance, please refer to suncasa's [https://suncasa-src.readthedocs.io/en/latest/autoapi/suncasa/eovsa/eovsa_dspec/index.html ReadtheDocs page].
[[File:TPSP.jpeg|center|500px]]

The following code will read the spectrogram file in IDL:

<pre style="background-color: #FCEBD9;">
function dspec,filename,doplot=doplot
; Read EOVSA Dynamic Spectrum FITS file <filename> and return a spectrogram object.
; Optionally show an overview plot if doplot switch is set
;
; Usage:
; s = dspec(<filename>) ; Returns spectrogram object
; s = dspec(<filename>,/doplot) ; Plots spectrum and returns spectrogram object
;
; To access the data in the spectrogram object, use
; spec = s.get(/spectrogram) (Array of amplitudes in SFU, of size ntimes, nfreq)
; fghz = s.get(/spectrum_axis) (Array of frequencies in GHz, of size nfreq)
; ut = s.get(/time_axis) (Array of UT times in anytim format, of size ntimes)

default,doplot,0
spec = mrdfits(filename,0)
freq = mrdfits(filename,1)
time = mrdfits(filename,2)
fghz = freq.sfreq
ut = anytim(time)
s = spectrogram(spec,ut,fghz)
if doplot then begin
window,/free,xsiz=1024,ysiz=600
; Find min and max of data from 5% to 95% of sorted array (eliminates outliers)
sarr = sort(spec)
dlim = minmax(spec[sarr[n_elements(sarr)*0.05:n_elements(sarr)*0.95]])
; Set drange with margin factor of 2 on low end and 5 on high end
s.set,drange=dlim*[0.5,5]
loadct,3
s.plot,/log,/xsty,/ysty,ytitle='Frequency [GHz]',charsize=1.5
endif
return,s
end
</pre>
[[File:IDL_TPSP.png|center|500px]]

====Synoptic 6-band Images====
Full disk images at 6 selected frequency bands centered at 1.4, 3.0, 4.5, 6.8, 10.2, and 13.9 GHz are provided once per day, calibrated in brightness temperature. [[File:synoptic_image.jpg| center |400px]]

The EOVSA full disk image FITS files are compressed with the RICE algorithm implemented in the FITS file handling module (astropy.io.fits) in Astropy. EOVSA FITS files are very similar to the compressed SDO/AIA FITS files from JSOC. Popular coding languages can easily read compressed images directly.

In IDL, you can use read_sdo in the ONTOLOGY package, which should be installed by default in SolarSoftWare (SSW), to read compressed EOVSA FITS files. The following code will read the EOVSA image FITS file in SSWIDL:

<pre style="background-color: #FCEBD9;">
read_sdo,'eovsa_20191225.spw11-20.tb.disk.fits',header,data,/UNCOMP_DELETE
index2map,header,data,eomap
plot_map,eomap
</pre>

[[File:eovsa_20191225_image_sswidl.jpg| center |250px]]

In Python, you can use SunPy map module to read EOVAS FITS files. SunPy is an open solar data analysis environment for Python. The installation instruction can be found at [https://sunpy.org/ SunPy official website].
<pre style="background-color: #FCEBD9;">
import matplotlib.pyplot as plt
from sunpy import map as smap
eofile='eovsa_20191225.spw11-20.tb.disk.fits'
eomap = smap.Map(eofile)
eomap.plot()
plt.show()
</pre>
[[File:eovsa_20191225_image_py.jpg| center |250px]]

EOVSA Data Products

2024-03-29T18:29:42Z

Dgary: /* Raw "Interim" Database (IDB) visibility data */

=Introduction=
EOVSA observes the full disk of the Sun at all times when the Sun is >10 degrees above the local horizon (season dependent and ranges from 7-12 hours duration centered on 20 UT). EOVSA records data at 451 science frequency channels each second, in four polarization products, as well as additional total flux measurements from each individual antenna. Figure 1 summarizes the different levels of data we produce. The later sections will give a more detailed description and usage examples.
[[File:pipeline_flowchart.jpg|center|600px|EOVSA pipeline block diagram/flow chart ]]

=Level 0 - Raw visibility data from the instrument=

As outlined in Figure 1, EOVSA creates raw data products in the left-hand column (labeled Level 0). This includes observations of cosmic sources for phase calibration, and gain and pointing observations required for total power calibration.

==Raw "Interim" Database (IDB) visibility data==
Full-resolution raw "Interim" Database (IDB) visibility data. They are stored in Miriad format, and hence may not be that useful for most people. Be patient after clicking the link--this is a very long list of directories, one for each available date. Recent data (latest few months) can be retrieved from the following page:

https://www.ovsa.njit.edu/fits/IDB/

For older data, visit

https://research.ssl.berkeley.edu/data/eovsa/IDB/

==Raw 1-min-averaged visibility data==
This is the same as for the IDB data, except with 1-minute time integration applied. This is typically not useful for flares, but is perfectly fine for imaging active regions and full Sun. These data can be retrieved from the following page:

http://www.ovsa.njit.edu/fits/UDB/

=Level 0.5 - Calibrated visibility data=
After applying calibration and other preliminary processing to the raw (level 0) data, we create the CASA ms’s in the second column in Figure 1 (labeled "level 0.5"). These visibility data are in the Fourier domain of the true images in the plane of the sky and are not immediately ready for spectral imaging analysis yet. However, they have all of the required content to produce images and spectrogram data in standard FITS format (level 1.0). We provide a set of standard ms’s for each day (red boxes in Figure 1), for use by researchers who know how to deal with visibility data. These data are more suitable for experienced users to exploit the full potential of EOVSA data, such as spatially resolved spectral analysis. Processing these data requires CASA or sunCASA (https://github.com/suncasa/suncasa-src). Please refer to our tutorial at [[EOVSA_Data_Analysis_Tutorial]].

==Calibrated full-resolution visibility data for flare events==
Calibrated and self-calibrated visibility data for flare events (purple boxes in Figure 1) will typically be available within 7 days after they are taken. They will be released at our flare list site soon: https://ovsa.njit.edu/flarelist

==Self-calibrated 1-min-averaged visibility data==
EOVSA 1-min averaged visibility data in CASA ms format can be retrieved from the following page:

http://www.ovsa.njit.edu/fits/UDBms_slfcaled

=Level 1.0 - Images and spectrogram data in standard FITS format =

Level 1.0 data are for users who prefer to work with spectrogram (frequency-time) and image data directly, which are also outputs of the pipeline system shown in Figure 1 (orange boxes). They are perfectly suitable to be used as context data for comparison with other multi-wavelength observations but are not (yet) intended for quantitative spatially resolved spectral analysis.

Spectrograms are provided as standard FITS tables containing the frequency list, list of times, and data in both total power (TP) and a sum of amplitudes over intermediate-length baselines (cross power or XP). Likewise, image data products are in FITS format with standard keywords and are converted into the Helioprojective Cartesian coordinate system compatible with the World Coordinate System (WCS) convention, along with correct registration for the spatial, spectral, and temporal coordinates. Both the spectrogram and image data products are calibrated and have physical radio intensity units (sfu for spectrograms and brightness temperature for radio images).

We provide the following level 1 data products:
* Synoptic products:
** '''All-day spectrograms''':
** '''All-day synoptic images''': Full disk images at 6 selected frequency bands centered at 1.4, 3.0, 4.5, 6.8, 10.2, and 13.9 GHz are produced once per day utilizing the earth-rotation synthesis, calibrated in brightness temperature. This is because EOVSA has a limited number of baselines and we need a long integration to fill up the uv domain in order to make full-disk images.
* Event-based products:
** '''Flare spectrograms''': These are full time and frequency resolution spectrograms produced from the median of calibrated cross-power visibilities in FITS format, cropped to cover the flare duration. Preflare background is also subtracted. Compared to total-power spectrograms, these spectrograms have the advantage of revealing details of the flare evolution by "filtering out" the large-scale, continuous background from the visibilities. Note that for certain flares that have a large source size, the flux can be lower than its true values (as a fraction of the flux will be "resolved out").
** '''Pipeline-produced spectral images''': We also have a semi-automated flare imaging pipeline to produce calibrated (and self-calibrated) images at 12-s cadence at up to 10 frequency bands. They are saved in standard FITS format and have been registered into Helioprojective coordinates. They can be read by SSWIDL or astropy/sunpy. These data have already been calibrated to physical units and are usually good to be compared with context data. But please be cautious when using them for quantitative spectral analysis.

{| class="wikitable"
|+ Summary of EOVSA Level 1 Data Products
|-
! scope="col"| Category
! scope="col"| Data Product
! scope="col"| Naming Convention
! scope="col"| Download Link
|-
! rowspan="2" | Synoptic Spectrograms
| All-day TP Spectrograms
| EOVSA_TPall_yyyymmdd.fts
!rowspan="9" | https://ovsa.njit.edu/browser
|-
| All-day XP Spectrograms
| EOVSA_XPall_yyyymmdd.fts
|-
! rowspan="7" | Synoptic Images
|-
| Synoptic 1.4 GHz images
| eovsa_yyyymmdd.spw00-01.tb.disk.fits
|-
| Synoptic 3.0 GHz images
| eovsa_yyyymmdd.spw02-05.tb.disk.fits
|-
| Synoptic 4.5 GHz images
| eovsa_yyyymmdd.spw06-10.tb.disk.fits
|-
| Synoptic 6.8 GHz images
| eovsa_yyyymmdd.spw11-20.tb.disk.fits
|-
| Synoptic 10.2 GHz images
| eovsa_yyyymmdd.spw21-30.tb.disk.fits
|-
| Synoptic 13.9 GHz images
| eovsa_yyyymmdd.spw31-43.tb.disk.fits
|-
! rowspan="1" | Flare Spectrograms
| Full-resolution cross-power Spectrogram
| eovsa.spec.flare_id_YYYYMMDDHHMMSS.fits
!rowspan="2" | https://ovsa.njit.edu/flarelist
|-
! rowspan="1" | Flare Spectral Images
| Pipeline-produced spectral images
| eovsa.lev1_mbd_12s.YYYY-MM-DDTHHMMSSZ.image.fits
|-
|}

==Browsing and Downloading level 1 data==
[[File:eovsa_browser.jpg|right|thumb|EOVSA Browser]]
[[file:EOVSA_flarelist.jpg|right|thumb|EOVSA Flare List]]
===Synoptic level 1 data===
EOVSA Level 1 synoptic data products can be retrieved with the following steps:
* Go to [http://ovsa.njit.edu/browser/ EOVSA browser] page.
* Browse to the date of interest.
* Click "synoptic fits" button next to the calendar tool.
* Select the data product based on the names listed in the table above.

===Flare level 1 data===
EOVSA flare list with spectrograms and spectral images can be queried and downloaded at https://ovsa.njit.edu/flarelist. Users can use the top box to select a time range of interest and query our flare list. The results are displayed in the dropdown box. An interactive plot of the flare light curves will be shown at the bottom of the page once an event is highlighted (by clicking on the flare ID). Quicklook plots and FITS files of the spectrograms and flare movies can be accessed by clicking the icons in each flare record.

==Reading and Using level 1 data==
===Introduction===
All our level 1 data products are in FITS format. All the images have standard, WCS-compatible coordinates. Users can use their favorite method to read these files. In the following, we provide minimal examples to read them with Astropy and Sunpy.

===Event-Based Data Products===
* An example of how to read and plot the flare spectrograms and images in Python (with Astropy and SunPy) can be accessed at [https://colab.research.google.com/drive/1Y3ONWCxLPYvWda5_LqFNxafJtwZDNJBD?usp=sharing#scrollTo=ueiMoHbdxfo- this Google Colab Jupyter notebook].
* We are working on an example with SSWIDL and will release it soon.

===Synoptic Data Products===

====All-day Spectrograms====
To read a spectrogram file in Python using the suncasa library:

<pre style="background-color: #FCEBD9;">
from suncasa.eovsa import eovsa_dspec as ds
from astropy.time import Time
from matplotlib.colors import LogNorm
## Read EOVSA Dynamic Spectrum FITS file <filename>
filename = 'EOVSA_TPall_20170713.fts'
s = ds.get_dspec(filename, doplot=True, cmap='gist_heat', norm=LogNorm(vmax=2.1e3, vmin=40))
## To access the data in the spectrogram object, use
spec = s['spectrogram'] ## (Array of amplitudes in SFU, of size nfreq,ntimes)
fghz = s['spectrum_axis'] ## (Array of frequencies in GHz, of size nfreq)
tim = Time(s['time_axis'], format='mjd') ## (Array of UT times in astropy.time object, of size ntimes)

</pre>

The '''get_dspec''' function is accessible on [https://github.com/suncasa/suncasa-src/blob/master/suncasa/eovsa/eovsa_dspec.py GitHub]. For comprehensive guidance, please refer to suncasa's [https://suncasa-src.readthedocs.io/en/latest/autoapi/suncasa/eovsa/eovsa_dspec/index.html ReadtheDocs page].
[[File:TPSP.jpeg|center|500px]]

The following code will read the spectrogram file in IDL:

<pre style="background-color: #FCEBD9;">
function dspec,filename,doplot=doplot
; Read EOVSA Dynamic Spectrum FITS file <filename> and return a spectrogram object.
; Optionally show an overview plot if doplot switch is set
;
; Usage:
; s = dspec(<filename>) ; Returns spectrogram object
; s = dspec(<filename>,/doplot) ; Plots spectrum and returns spectrogram object
;
; To access the data in the spectrogram object, use
; spec = s.get(/spectrogram) (Array of amplitudes in SFU, of size ntimes, nfreq)
; fghz = s.get(/spectrum_axis) (Array of frequencies in GHz, of size nfreq)
; ut = s.get(/time_axis) (Array of UT times in anytim format, of size ntimes)

default,doplot,0
spec = mrdfits(filename,0)
freq = mrdfits(filename,1)
time = mrdfits(filename,2)
fghz = freq.sfreq
ut = anytim(time)
s = spectrogram(spec,ut,fghz)
if doplot then begin
window,/free,xsiz=1024,ysiz=600
; Find min and max of data from 5% to 95% of sorted array (eliminates outliers)
sarr = sort(spec)
dlim = minmax(spec[sarr[n_elements(sarr)*0.05:n_elements(sarr)*0.95]])
; Set drange with margin factor of 2 on low end and 5 on high end
s.set,drange=dlim*[0.5,5]
loadct,3
s.plot,/log,/xsty,/ysty,ytitle='Frequency [GHz]',charsize=1.5
endif
return,s
end
</pre>
[[File:IDL_TPSP.png|center|500px]]

====Synoptic 6-band Images====
Full disk images at 6 selected frequency bands centered at 1.4, 3.0, 4.5, 6.8, 10.2, and 13.9 GHz are provided once per day, calibrated in brightness temperature. [[File:synoptic_image.jpg| center |400px]]

The EOVSA full disk image FITS files are compressed with the RICE algorithm implemented in the FITS file handling module (astropy.io.fits) in Astropy. EOVSA FITS files are very similar to the compressed SDO/AIA FITS files from JSOC. Popular coding languages can easily read compressed images directly.

In IDL, you can use read_sdo in the ONTOLOGY package, which should be installed by default in SolarSoftWare (SSW), to read compressed EOVSA FITS files. The following code will read the EOVSA image FITS file in SSWIDL:

<pre style="background-color: #FCEBD9;">
read_sdo,'eovsa_20191225.spw11-20.tb.disk.fits',header,data,/UNCOMP_DELETE
index2map,header,data,eomap
plot_map,eomap
</pre>

[[File:eovsa_20191225_image_sswidl.jpg| center |250px]]

In Python, you can use SunPy map module to read EOVAS FITS files. SunPy is an open solar data analysis environment for Python. The installation instruction can be found at [https://sunpy.org/ SunPy official website].
<pre style="background-color: #FCEBD9;">
import matplotlib.pyplot as plt
from sunpy import map as smap
eofile='eovsa_20191225.spw11-20.tb.disk.fits'
eomap = smap.Map(eofile)
eomap.plot()
plt.show()
</pre>
[[File:eovsa_20191225_image_py.jpg| center |250px]]

EOVSA Data Products

2024-03-29T18:29:12Z

Dgary: /* Raw "Interim" Database (IDB) visibility data */

=Introduction=
EOVSA observes the full disk of the Sun at all times when the Sun is >10 degrees above the local horizon (season dependent and ranges from 7-12 hours duration centered on 20 UT). EOVSA records data at 451 science frequency channels each second, in four polarization products, as well as additional total flux measurements from each individual antenna. Figure 1 summarizes the different levels of data we produce. The later sections will give a more detailed description and usage examples.
[[File:pipeline_flowchart.jpg|center|600px|EOVSA pipeline block diagram/flow chart ]]

=Level 0 - Raw visibility data from the instrument=

As outlined in Figure 1, EOVSA creates raw data products in the left-hand column (labeled Level 0). This includes observations of cosmic sources for phase calibration, and gain and pointing observations required for total power calibration.

==Raw "Interim" Database (IDB) visibility data==
Full-resolution raw "Interim" Database (IDB) visibility data. They are stored in Miriad format, and hence may not be that useful for most people. Be patient after clicking the link--this is a very long list of directories, one for each available date. Recent data (latest few months) can be retrieved from the following page:

https://www.ovsa.njit.edu/fits/IDB/

For older data, visit

https://research.ssl.berkeley.edu/data/eovsa/

==Raw 1-min-averaged visibility data==
This is the same as for the IDB data, except with 1-minute time integration applied. This is typically not useful for flares, but is perfectly fine for imaging active regions and full Sun. These data can be retrieved from the following page:

http://www.ovsa.njit.edu/fits/UDB/

=Level 0.5 - Calibrated visibility data=
After applying calibration and other preliminary processing to the raw (level 0) data, we create the CASA ms’s in the second column in Figure 1 (labeled "level 0.5"). These visibility data are in the Fourier domain of the true images in the plane of the sky and are not immediately ready for spectral imaging analysis yet. However, they have all of the required content to produce images and spectrogram data in standard FITS format (level 1.0). We provide a set of standard ms’s for each day (red boxes in Figure 1), for use by researchers who know how to deal with visibility data. These data are more suitable for experienced users to exploit the full potential of EOVSA data, such as spatially resolved spectral analysis. Processing these data requires CASA or sunCASA (https://github.com/suncasa/suncasa-src). Please refer to our tutorial at [[EOVSA_Data_Analysis_Tutorial]].

==Calibrated full-resolution visibility data for flare events==
Calibrated and self-calibrated visibility data for flare events (purple boxes in Figure 1) will typically be available within 7 days after they are taken. They will be released at our flare list site soon: https://ovsa.njit.edu/flarelist

==Self-calibrated 1-min-averaged visibility data==
EOVSA 1-min averaged visibility data in CASA ms format can be retrieved from the following page:

http://www.ovsa.njit.edu/fits/UDBms_slfcaled

=Level 1.0 - Images and spectrogram data in standard FITS format =

Level 1.0 data are for users who prefer to work with spectrogram (frequency-time) and image data directly, which are also outputs of the pipeline system shown in Figure 1 (orange boxes). They are perfectly suitable to be used as context data for comparison with other multi-wavelength observations but are not (yet) intended for quantitative spatially resolved spectral analysis.

Spectrograms are provided as standard FITS tables containing the frequency list, list of times, and data in both total power (TP) and a sum of amplitudes over intermediate-length baselines (cross power or XP). Likewise, image data products are in FITS format with standard keywords and are converted into the Helioprojective Cartesian coordinate system compatible with the World Coordinate System (WCS) convention, along with correct registration for the spatial, spectral, and temporal coordinates. Both the spectrogram and image data products are calibrated and have physical radio intensity units (sfu for spectrograms and brightness temperature for radio images).

We provide the following level 1 data products:
* Synoptic products:
** '''All-day spectrograms''':
** '''All-day synoptic images''': Full disk images at 6 selected frequency bands centered at 1.4, 3.0, 4.5, 6.8, 10.2, and 13.9 GHz are produced once per day utilizing the earth-rotation synthesis, calibrated in brightness temperature. This is because EOVSA has a limited number of baselines and we need a long integration to fill up the uv domain in order to make full-disk images.
* Event-based products:
** '''Flare spectrograms''': These are full time and frequency resolution spectrograms produced from the median of calibrated cross-power visibilities in FITS format, cropped to cover the flare duration. Preflare background is also subtracted. Compared to total-power spectrograms, these spectrograms have the advantage of revealing details of the flare evolution by "filtering out" the large-scale, continuous background from the visibilities. Note that for certain flares that have a large source size, the flux can be lower than its true values (as a fraction of the flux will be "resolved out").
** '''Pipeline-produced spectral images''': We also have a semi-automated flare imaging pipeline to produce calibrated (and self-calibrated) images at 12-s cadence at up to 10 frequency bands. They are saved in standard FITS format and have been registered into Helioprojective coordinates. They can be read by SSWIDL or astropy/sunpy. These data have already been calibrated to physical units and are usually good to be compared with context data. But please be cautious when using them for quantitative spectral analysis.

{| class="wikitable"
|+ Summary of EOVSA Level 1 Data Products
|-
! scope="col"| Category
! scope="col"| Data Product
! scope="col"| Naming Convention
! scope="col"| Download Link
|-
! rowspan="2" | Synoptic Spectrograms
| All-day TP Spectrograms
| EOVSA_TPall_yyyymmdd.fts
!rowspan="9" | https://ovsa.njit.edu/browser
|-
| All-day XP Spectrograms
| EOVSA_XPall_yyyymmdd.fts
|-
! rowspan="7" | Synoptic Images
|-
| Synoptic 1.4 GHz images
| eovsa_yyyymmdd.spw00-01.tb.disk.fits
|-
| Synoptic 3.0 GHz images
| eovsa_yyyymmdd.spw02-05.tb.disk.fits
|-
| Synoptic 4.5 GHz images
| eovsa_yyyymmdd.spw06-10.tb.disk.fits
|-
| Synoptic 6.8 GHz images
| eovsa_yyyymmdd.spw11-20.tb.disk.fits
|-
| Synoptic 10.2 GHz images
| eovsa_yyyymmdd.spw21-30.tb.disk.fits
|-
| Synoptic 13.9 GHz images
| eovsa_yyyymmdd.spw31-43.tb.disk.fits
|-
! rowspan="1" | Flare Spectrograms
| Full-resolution cross-power Spectrogram
| eovsa.spec.flare_id_YYYYMMDDHHMMSS.fits
!rowspan="2" | https://ovsa.njit.edu/flarelist
|-
! rowspan="1" | Flare Spectral Images
| Pipeline-produced spectral images
| eovsa.lev1_mbd_12s.YYYY-MM-DDTHHMMSSZ.image.fits
|-
|}

==Browsing and Downloading level 1 data==
[[File:eovsa_browser.jpg|right|thumb|EOVSA Browser]]
[[file:EOVSA_flarelist.jpg|right|thumb|EOVSA Flare List]]
===Synoptic level 1 data===
EOVSA Level 1 synoptic data products can be retrieved with the following steps:
* Go to [http://ovsa.njit.edu/browser/ EOVSA browser] page.
* Browse to the date of interest.
* Click "synoptic fits" button next to the calendar tool.
* Select the data product based on the names listed in the table above.

===Flare level 1 data===
EOVSA flare list with spectrograms and spectral images can be queried and downloaded at https://ovsa.njit.edu/flarelist. Users can use the top box to select a time range of interest and query our flare list. The results are displayed in the dropdown box. An interactive plot of the flare light curves will be shown at the bottom of the page once an event is highlighted (by clicking on the flare ID). Quicklook plots and FITS files of the spectrograms and flare movies can be accessed by clicking the icons in each flare record.

==Reading and Using level 1 data==
===Introduction===
All our level 1 data products are in FITS format. All the images have standard, WCS-compatible coordinates. Users can use their favorite method to read these files. In the following, we provide minimal examples to read them with Astropy and Sunpy.

===Event-Based Data Products===
* An example of how to read and plot the flare spectrograms and images in Python (with Astropy and SunPy) can be accessed at [https://colab.research.google.com/drive/1Y3ONWCxLPYvWda5_LqFNxafJtwZDNJBD?usp=sharing#scrollTo=ueiMoHbdxfo- this Google Colab Jupyter notebook].
* We are working on an example with SSWIDL and will release it soon.

===Synoptic Data Products===

====All-day Spectrograms====
To read a spectrogram file in Python using the suncasa library:

<pre style="background-color: #FCEBD9;">
from suncasa.eovsa import eovsa_dspec as ds
from astropy.time import Time
from matplotlib.colors import LogNorm
## Read EOVSA Dynamic Spectrum FITS file <filename>
filename = 'EOVSA_TPall_20170713.fts'
s = ds.get_dspec(filename, doplot=True, cmap='gist_heat', norm=LogNorm(vmax=2.1e3, vmin=40))
## To access the data in the spectrogram object, use
spec = s['spectrogram'] ## (Array of amplitudes in SFU, of size nfreq,ntimes)
fghz = s['spectrum_axis'] ## (Array of frequencies in GHz, of size nfreq)
tim = Time(s['time_axis'], format='mjd') ## (Array of UT times in astropy.time object, of size ntimes)

</pre>

The '''get_dspec''' function is accessible on [https://github.com/suncasa/suncasa-src/blob/master/suncasa/eovsa/eovsa_dspec.py GitHub]. For comprehensive guidance, please refer to suncasa's [https://suncasa-src.readthedocs.io/en/latest/autoapi/suncasa/eovsa/eovsa_dspec/index.html ReadtheDocs page].
[[File:TPSP.jpeg|center|500px]]

The following code will read the spectrogram file in IDL:

<pre style="background-color: #FCEBD9;">
function dspec,filename,doplot=doplot
; Read EOVSA Dynamic Spectrum FITS file <filename> and return a spectrogram object.
; Optionally show an overview plot if doplot switch is set
;
; Usage:
; s = dspec(<filename>) ; Returns spectrogram object
; s = dspec(<filename>,/doplot) ; Plots spectrum and returns spectrogram object
;
; To access the data in the spectrogram object, use
; spec = s.get(/spectrogram) (Array of amplitudes in SFU, of size ntimes, nfreq)
; fghz = s.get(/spectrum_axis) (Array of frequencies in GHz, of size nfreq)
; ut = s.get(/time_axis) (Array of UT times in anytim format, of size ntimes)

default,doplot,0
spec = mrdfits(filename,0)
freq = mrdfits(filename,1)
time = mrdfits(filename,2)
fghz = freq.sfreq
ut = anytim(time)
s = spectrogram(spec,ut,fghz)
if doplot then begin
window,/free,xsiz=1024,ysiz=600
; Find min and max of data from 5% to 95% of sorted array (eliminates outliers)
sarr = sort(spec)
dlim = minmax(spec[sarr[n_elements(sarr)*0.05:n_elements(sarr)*0.95]])
; Set drange with margin factor of 2 on low end and 5 on high end
s.set,drange=dlim*[0.5,5]
loadct,3
s.plot,/log,/xsty,/ysty,ytitle='Frequency [GHz]',charsize=1.5
endif
return,s
end
</pre>
[[File:IDL_TPSP.png|center|500px]]

====Synoptic 6-band Images====
Full disk images at 6 selected frequency bands centered at 1.4, 3.0, 4.5, 6.8, 10.2, and 13.9 GHz are provided once per day, calibrated in brightness temperature. [[File:synoptic_image.jpg| center |400px]]

The EOVSA full disk image FITS files are compressed with the RICE algorithm implemented in the FITS file handling module (astropy.io.fits) in Astropy. EOVSA FITS files are very similar to the compressed SDO/AIA FITS files from JSOC. Popular coding languages can easily read compressed images directly.

In IDL, you can use read_sdo in the ONTOLOGY package, which should be installed by default in SolarSoftWare (SSW), to read compressed EOVSA FITS files. The following code will read the EOVSA image FITS file in SSWIDL:

<pre style="background-color: #FCEBD9;">
read_sdo,'eovsa_20191225.spw11-20.tb.disk.fits',header,data,/UNCOMP_DELETE
index2map,header,data,eomap
plot_map,eomap
</pre>

[[File:eovsa_20191225_image_sswidl.jpg| center |250px]]

In Python, you can use SunPy map module to read EOVAS FITS files. SunPy is an open solar data analysis environment for Python. The installation instruction can be found at [https://sunpy.org/ SunPy official website].
<pre style="background-color: #FCEBD9;">
import matplotlib.pyplot as plt
from sunpy import map as smap
eofile='eovsa_20191225.spw11-20.tb.disk.fits'
eomap = smap.Map(eofile)
eomap.plot()
plt.show()
</pre>
[[File:eovsa_20191225_image_py.jpg| center |250px]]

Owens Valley Solar Arrays

2024-03-15T16:02:01Z

Dgary: /* EOVSA Publications */

[[File:Eovsa1.png|border|text-top|800px]]

<big>[http://ovsa.njit.edu/ EOVSA] (Expanded Owens Valley Solar Array) is a solar-dedicated radio interferometer operated by the New Jersey Institute of Technology and serving as a '''National Science Foundation Geospace Facility'''. [[File:NSF.jpg|70px]]
<pre>Operation of EOVSA is supported by the National Science Foundation under Grant No. AGS-2130832. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. </pre>
This wiki serves as the site for EOVSA documentation. </big>

[[File:OVRO-LWA1.png|border|text-top|800px]]

<big>OVRO-LWA (Owens Valley Radio Observatory Long Wavelength Array) is an all-sky imager that has a new solar-dedicated spectroscopic imaging mode. OVRO-LWA is a multi-institutional collaboration led by Caltech. NJIT Solar Radio Group is leading its solar-mode development and science. At the bottom of this page are new links for that facility. </big>

== EOVSA Documentation ==

* <big>General</big>
** [[Downconversion and Frequency Tuning]]
** [[Dealing with Radio Frequency Interference]]
** [[Switching between 200 MHz and 300 MHz Correlator]]
** [[Observing in "Fast" Mode]]

* <big>Computer-Network</big>
** [[Computing Systems]]
** [[Network]]

* <big>Control System</big>
** [[27-m Antenna Commands]]
** [[Schedule Commands]]
** [[Control Commands]]
** [[Attenuation and Level Control]]

* <big>Hardware</big>
** [[Hardware Overview]]
** [[2.1-m Antennas]]
** [[27-m Antennas]]

* <big>System Software</big>
** [[Calibration Database]]
** [[Stateframe Database]]
** [[Database Maintenance]]
** [[Create CASA measurement sets]]

* <big>Calibration</big>
**[[Calibration Overview]]
**[[Pointing Calibration]]
**[[Total Power Calibration]]
**[[System Gain Calibration]]
**[[Antenna Position]] (Baseline Calibration)
**[[Reference Gain Calibration]]
**[[Daily Gain Calibration]]
**[[Delay Calibration]]
**[[Bandpass Calibration]]
**[[Polarization Calibration]]
**[[Calibrator Survey]]
**[[Practical Calibration Tutorial]]

* <big>[[Starburst]]</big>

== Using EOVSA Data ==
* <big>[[EOVSA Data products]]</big>
* <big>Analysis Software</big>
** [https://github.com/suncasa/suncasa SunCASA] A wrapper around [https://casa.nrao.edu/ CASA (the Common Astronomy Software Applications package)] for synthesis imaging and visualizing solar spectral imaging data. CASA is one of the leading software tool for "supporting the data post-processing needs of the next generation of radio astronomical telescopes such as ALMA and VLA", an international effort led by the [https://public.nrao.edu/ National Radio Astronomy Observatory]. The current version of CASA uses Python (2.7) interface. More information about CASA can be found on [https://casa.nrao.edu/ NRAO's CASA website ]. Note, CASA is available ONLY on UNIX-BASED PLATFORMS (and therefore, so is SunCASA).
** [https://github.com/Gelu-Nita/GSFIT GSFIT] A IDL-widget(GUI)-based spectral fitting package called gsfit, which provides a user-friendly display of EOVSA image cubes and an interface to fast fitting codes (via platform-dependent shared-object libraries).
** [[Spectrogram Software]]
** [[Mapping Software]]
* <big>Data Analysis Guides</big>
** <big>[[EOVSA Data Analysis Tutorial 2022]]</big> and <big>[https://colab.research.google.com/drive/19NQb6Emb9HvKX4QHq9ZYCP3RM6nT7sDL#scrollTo=cLdDVptBGG-X EOVSA Workspace]</big> at [https://sphere.boulder.swri.edu/ SPHERE 2022 Workshop]
** <big>[https://colab.research.google.com/drive/1lSLLxgOG6b8kgu9Sk6kSKvrViyubnXG6?usp=sharing#scrollTo=xbXyyLmCFCGL EOVSA Data Analysis Tutorial at RHESSI 19 Workshop]</big>
** <big>[[EOVSA Data Analysis Tutorial]]</big> at [http://rhessi18.umn.edu/ RHESSI XVIII Workshop]
** [[Self-Calibrating Flare Data]] Example script and guides for self-calibrating EOVSA flare data (to be completed)


**[[IDB flare pipeline]] Tutorial to run the flare pipeline for quicklook images



* <big>EOVSA Modeling Guide</big>
**[[GX Simulator]]

* Other helpful links
** [https://casaguides.nrao.edu CASA Guides]
** [http://www.lmsal.com/solarsoft/ SolarSoft IDL]
** [http://www.atnf.csiro.au/computing/software/miriad/userguide/userhtml.html Miriad Guides]
** [https://sites.google.com/site/fgscodes/ Fast Gyrosynchrotron Codes (Alexey Kuznetsov's website)]
** [[Basic GitHub Tutorial]]


* <big>[[Full Disk Simulations]]</big>
* <big>[[All-Day Synthesis Issues]]</big>
* <big>[[Analyzing Pre-2017 Data]]</big>
* <big>[[Fixing Pipeline Problems pre-2021-Feb-07]]</big>

== System Software ==

* LabVIEW software
* Python code [https://github.com/dgary50/eovsa Github repository]
* [[Python3 Code Installation]]

== EOVSA Observing Log ==
[[2016 November]]; [[2016 December| December]]

[[2017 January]]; [[2017 February | February]]; [[2017 March | March]]; [[2017 April | April]]; [[2017 May | May]]; [[2017 June | June]];
[[2017 July | July]]; [[2017 August | August]]; [[2017 September | September]]; [[2017 October | October]]; [[2017 November | November]]; [[2017 December | December]]

[[2018 January]]; [[2018 February | February]]; [[2018 March | March]]; [[2018 April | April]]; [[2018 May | May]]; [[2018 June | June]];
[[2018 July | July]]; [[2018 August | August]]; [[2018 September | September]]; [[2018 October | October]]; [[2018 November | November]]; [[2018 December | December]]

[[2019 January]]; [[2019 February | February]]; [[2019 March | March]]; [[2019 April | April]]; [[2019 May | May]]; [[2019 June | June]];
[[2019 July | July]]; [[2019 August | August]]; [[2019 September | September]]; [[2019 October | October]]; [[2019 November | November]]; [[2019 December | December]]

[[2020 January]]; [[2020 February | February]]; [[2020 March | March]]; [[2020 April | April]]; [[2020 May | May]]; [[2020 June | June]];
[[2020 July | July]]; [[2020 August | August]]; [[2020 September | September]]; [[2020 October | October]]; [[2020 November | November]]; [[2020 December | December]]

[[2021 January]]; [[2021 February | February]]; [[2021 March | March]]; [[2021 April | April]]; [[2021 May | May]]; [[2021 June | June]];
[[2021 July | July]]; [[2021 August | August]]; [[2021 September | September]]; [[2021 October | October]]; [[2021 November | November]]; [[2021 December | December]]

[[2022 SQL Outage]]

[[2023 January]]; [[2023 February | February]]; [[2023 March | March]]; [[2023 April | April]]; [[2023 May | May]]; [[2023 June | June]];
[[2023 July | July]]; [[2023 August | August]]; [[2023 September | September]]; [[2023 October | October]]; [[2023 November | November]]; [[2023 December | December]]

[[2024 January]]; [[2024 February | February]]; [[2024 March | March]];

== Tohbans ==

[[Trouble Shooting Guide]]

[[Tohban Records]]

[[Owen's Notes]]

[[Caius' Notes]]

[[Tohban EOVSA Imaging Tutorial A-Z]]

[[Tohban OVRO-LWA Imaging Tutorial]]

[[Tohban Guide to Self Calibration and Imaging for EOVSA]]

[[Guide to Upgrade SolarSoft(SSW)]]

== EOVSA Flare List ==

See [https://docs.google.com/spreadsheets/d/1P8jHuDRF93dMflU6RMQcsJqVepD9vFkPkofV8Imj4xA/edit?usp=sharing this link] for a list of EOVSA flares as a Google Spreadsheet.

[[Recent Flare List (2021-)]]

[http://ovsa.njit.edu/jay/rd_db.php An older link] is available at the EOVSA website.

[[Instructions on using data downloaded from the flare list]]

== EOVSA Publications ==
Here is a (partial) list of publications that utilize EOVSA data. See also the collection of EOVSA publications at [https://ui.adsabs.harvard.edu/public-libraries/eQ7HfPkySqydu-B8BCt6QQ this NASA/ADS Library].
; 2024
: Collier, H., Hayes, L. A., Yu, S., Battaglia, A. F., Ashfield, W., Polito, V., Harra, L. K., & Krucker, S. (2024), arXiv e-prints, arXiv:2402.10546. [https://ui.adsabs.harvard.edu/abs/2024arXiv240210546C “Localising pulsations in the hard X-ray and microwave emission of an X-class flare”]
: Saqri, J., Veronig, A. M., Battaglia, A. F., Dickson, E. C. M., Gary, D. E., & Krucker, S. (2024), Astronomy and Astrophysics, 683, A41. [https://ui.adsabs.harvard.edu/abs/2024A&A...683A..41S "Efficiency of solar microflares in accelerating electrons when rooted in a sunspot"]
; 2023
: Tan, B., Yan, Y., Huang, J., Zhang, Y., Tan, C., & Zhu, X. (2023), Advances in Space Research, 72, 5563. [https://ui.adsabs.harvard.edu/abs/2023AdSpR..72.5563T "The physics of solar spectral imaging observations in dm-cm wavelengths and the application on space weather"]

: Li, D., Li, Z., Shi, F., Su, Y., Chen, W., Yu, F., Li, C., Qiu, Y., Huang, Y., & Ning, Z. (2023), Astronomy and Astrophysics, 680, L15. [https://ui.adsabs.harvard.edu/abs/2023A&A...680L..15L "Observational signature of continuously operating drivers of decayless kink oscillation"]

: Wang, M., Chen, B., Yu, S., Gary, D. E., Lee, J., Wang, H., & Cohen, C. (2023), The Astrophysical Journal, 954, 32. [https://ui.adsabs.harvard.edu/abs/2023ApJ...954...32W "The Solar Origin of an In Situ Type III Radio Burst Event"]

: Gary, D. E. (2023), Annual Review of Astronomy and Astrophysics, 61, 427. [https://ui.adsabs.harvard.edu/abs/2023ARA&A..61..427G "New Insights from Imaging Spectroscopy of Solar Radio Emission"]

: Nita, G. M., Fleishman, G. D., Kuznetsov, A. A., Anfinogentov, S. A., Stupishin, A. G., Kontar, E. P., Schonfeld, S. J., Klimchuk, J. A., & Gary, D. E. (2023), The Astrophysical Journal Supplement Series, 267, 6. [https://ui.adsabs.harvard.edu/abs/2023ApJS..267....6N "Data-constrained Solar Modeling with GX Simulator"]

: Song, D.-C., Tian, J., Li, Y., Ding, M. D., Su, Y., Yu, S., Hong, J., Qiu, Y., Rao, S., Liu, X., Li, Q., Chen, X., Li, C., & Fang, C. (2023), The Astrophysical Journal, 952, L6. [https://ui.adsabs.harvard.edu/abs/2023ApJ...952L...6S "Spectral Observations and Modeling of a Solar White-light Flare Observed by CHASE"]

: Mondal, S., Chen, B., & Yu, S. (2023), The Astrophysical Journal, 949, 56. [https://ui.adsabs.harvard.edu/abs/2023ApJ...949...56M "Multifrequency Microwave Imaging of Weak Transients from the Quiet Solar Corona"]

: Kontar, E. P., Emslie, A. G., Motorina, G. G., & Dennis, B. R. (2023), The Astrophysical Journal, 947, L13. [https://ui.adsabs.harvard.edu/abs/2023ApJ...947L..13K "The Efficiency of Electron Acceleration during the Impulsive Phase of a Solar Flare"]

: Saqri, J., Veronig, A. M., Dickson, E. C. M., Podladchikova, T., Warmuth, A., Xiao, H., Gary, D. E., Battaglia, A. F., & Krucker, S. (2023), Astronomy and Astrophysics, 672, A23. [https://ui.adsabs.harvard.edu/abs/2023A&A...672A..23S "Multi-point study of the energy release and impulsive CME dynamics in an eruptive C7 flare"]
; 2022

: Kou, Y., Cheng, X., Wang, Y., Yu, S., Chen, B., Kontar, E. P., & Ding, M. (2022), Nature Communications, 13, 7680. [https://ui.adsabs.harvard.edu/abs/2022NatCo..13.7680K "Microwave imaging of quasi-periodic pulsations at flare current sheet"]

: Chertok, I. M. (2022), Monthly Notices of the Royal Astronomical Society, 517, 2709. [https://ui.adsabs.harvard.edu/abs/2022MNRAS.517.2709C "On some features of the solar proton event on 2021 October 28 - GLE73"]

: Lörinčík, J., Polito, V., De Pontieu, B., Yu, S., & Freij, N. (2022), Frontiers in Astronomy and Space Sciences, 9, 334. [https://ui.adsabs.harvard.edu/abs/2022FrASS...940945L "Rapid variations of Si IV spectra in a flare observed by interface region imaging spectrograph at a sub-second cadence"]

: Klein, K.-L., Musset, S., Vilmer, N., Briand, C., Krucker, S., Francesco Battaglia, A., Dresing, N., Palmroos, C., & Gary, D. E. (2022), Astronomy and Astrophysics, 663, A173. [https://ui.adsabs.harvard.edu/abs/2022A&A...663A.173K "The relativistic solar particle event on 28 October 2021: Evidence of particle acceleration within and escape from the solar corona"]

: Fleishman, G. D., Nita, G. M., Chen, B., Yu, S., & Gary, D. E. (2022), Nature, 606, 674. [https://ui.adsabs.harvard.edu/abs/2022Natur.606..674F "Solar flare accelerates nearly all electrons in a large coronal volume"]

: Li, X., Guo, F., Chen, B., Shen, C., & Glesener, L. (2022), The Astrophysical Journal, 932, 92. [https://ui.adsabs.harvard.edu/abs/2022ApJ...932...92L "Modeling Electron Acceleration and Transport in the Early Impulsive Phase of the 2017 September 10th Solar Flare"]

: Zhang, J., Chen, B., Yu, S., Tian, H., Wei, Y., Chen, H., Tan, G., Luo, Y., & Chen, X. (2022), The Astrophysical Journal, 932, 53. [https://ui.adsabs.harvard.edu/abs/2022ApJ...932...53Z "Implications for Additional Plasma Heating Driving the Extreme-ultraviolet Late Phase of a Solar Flare with Microwave Imaging Spectroscopy"]

: Liu, N., Jing, J., Xu, Y., & Wang, H. (2022), The Astrophysical Journal, 930, 154. [https://ui.adsabs.harvard.edu/abs/2022ApJ...930..154L "Multi-instrument Comparative Study of Temperature, Number Density, and Emission Measure during the Precursor Phase of a Solar Flare"]

: López, F. M., Giménez de Castro, C. G., Mandrini, C. H., Simões, P. J. A., Cristiani, G. D., Gary, D. E., Francile, C., & Démoulin, P. (2022), Astronomy and Astrophysics, 657, A51. [https://ui.adsabs.harvard.edu/abs/2022A&A...657A..51L "A solar flare driven by thermal conduction observed in mid-infrared"]

: Unverferth, J., & Longcope, D. (2021), The Astrophysical Journal, 923, 248. [https://ui.adsabs.harvard.edu/abs/2021ApJ...923..248U "Examining Flux Tube Interactions as a Cause of Sub-alfvénic Outflow"]
;2021

: Wei, Y., Chen, B., Yu, S., Wang, H., Jing, J., & Gary, D. E. (2021), The Astrophysical Journal, 923, 213. [https://ui.adsabs.harvard.edu/abs/2021ApJ...923..213W "Coronal Magnetic Field Measurements along a Partially Erupting Filament in a Solar Flare"]

: Jing, J., Inoue, S., Lee, J., Li, Q., Nita, G. M., Xu, Y., Liu, C., Gary, D. E., & Wang, H. (2021), The Astrophysical Journal, 922, 108. [https://ui.adsabs.harvard.edu/abs/2021ApJ...922..108J "Understanding the Initiation of the M2.4 Flare on 2017 July 14"]

: Battaglia, A. F., Saqri, J., Massa, P., Perracchione, E., Dickson, E. C. M., Xiao, H., Veronig, A. M., Warmuth, A., Battaglia, M., Hurford, G. J., Meuris, A., Limousin, O., Etesi, L., Maloney, S. A., Schwartz, R. A., Kuhar, M., Schuller, F., Senthamizh Pavai, V., Musset, S., Ryan, D. F., Kleint, L., Piana, M., Massone, A. M., Benvenuto, F., Sylwester, J., Litwicka, M., Stȩślicki, M., Mrozek, T., Vilmer, N., Fárník, F., Kašparová, J., Mann, G., Gallagher, P. T., Dennis, B. R., Csillaghy, A., Benz, A. O., & Krucker, S. (2021), Astronomy and Astrophysics, 656, A4. [https://ui.adsabs.harvard.edu/abs/2021A&A...656A...4B "STIX X-ray microflare observations during the Solar Orbiter commissioning phase"]

: Shaik, S. B., & Gary, D. E. (2021), The Astrophysical Journal, 919, 44. [https://ui.adsabs.harvard.edu/abs/2021ApJ...919...44S "Implications of Flat Optically Thick Microwave Spectra in Solar Flares for Source Size and Morphology"]

: Kocharov, L., Omodei, N., Mishev, A., Pesce-Rollins, M., Longo, F., Yu, S., Gary, D. E., Vainio, R., & Usoskin, I. (2021), The Astrophysical Journal, 915, 12. [https://ui.adsabs.harvard.edu/abs/2021ApJ...915...12K "Multiple Sources of Solar High-energy Protons"]

: Chen, B., Battaglia, M., Krucker, S., Reeves, K. K., & Glesener, L. (2021), The Astrophysical Journal, 908, L55. [https://ui.adsabs.harvard.edu/abs/2021ApJ...908L..55C "Energetic Electron Distribution of the Coronal Acceleration Region: First Results from Joint Microwave and Hard X-Ray Imaging Spectroscopy"]

: Chhabra, S., Gary, D. E., Hallinan, G., Anderson, M. M., Chen, B., Greenhill, L. J., & Price, D. C. (2021), The Astrophysical Journal, 906, 132. [https://ui.adsabs.harvard.edu/abs/2021ApJ...906..132C "Imaging Spectroscopy of CME-associated Solar Radio Bursts using OVRO-LWA"]
;2020 and earlier

: Reeves, K. K., Polito, V., Chen, B., Galan, G., Yu, S., Liu, W., & Li, G. (2020), The Astrophysical Journal, 905, 165. [https://ui.adsabs.harvard.edu/abs/2020ApJ...905..165R "Hot Plasma Flows and Oscillations in the Loop-top Region During the 2017 September 10 X8.2 Solar Flare"]

: Nindos, A. (2020), Frontiers in Astronomy and Space Sciences, 7, 57. [https://ui.adsabs.harvard.edu/abs/2020FrASS...7...57N "Incoherent Solar Radio Emission"]

: Yu, S., Chen, B., Reeves, K. K., Gary, D. E., Musset, S., Fleishman, G. D., Nita, G. M., & Glesener, L. (2020), The Astrophysical Journal, 900, 17. [https://ui.adsabs.harvard.edu/abs/2020ApJ...900...17Y "Magnetic Reconnection during the Post-impulsive Phase of a Long-duration Solar Flare: Bidirectional Outflows as a Cause of Microwave and X-Ray Bursts"]

: Chen, B., Yu, S., Reeves, K. K., & Gary, D. E. (2020), The Astrophysical Journal, 895, L50. [https://ui.adsabs.harvard.edu/abs/2020ApJ...895L..50C "Microwave Spectral Imaging of an Erupting Magnetic Flux Rope: Implications for the Standard Solar Flare Model in Three Dimensions"]

: Kuroda, N., Fleishman, G. D., Gary, D. E., Nita, G. M., Chen, B., & Yu, S. (2020), Frontiers in Astronomy and Space Sciences, 7, 22. [https://ui.adsabs.harvard.edu/abs/2020FrASS...7...22K "Evolution of Flare-accelerated Electrons Quantified by Spatially Resolved Analysis"]

: Glesener, L., Krucker, S., Duncan, J., Hannah, I. G., Grefenstette, B. W., Chen, B., Smith, D. M., White, S. M., & Hudson, H. (2020), The Astrophysical Journal, 891, L34. [https://ui.adsabs.harvard.edu/abs/2020ApJ...891L..34G "Accelerated Electrons Observed Down to <7 keV in a NuSTAR Solar Microflare"]

: Karlický, M., Chen, B., Gary, D. E., Kašparová, J., & Rybák, J. (2020), The Astrophysical Journal, 889, 72. [https://ui.adsabs.harvard.edu/abs/2020ApJ...889...72K "Drifting Pulsation Structure at the Very Beginning of the 2017 September 10 Limb Flare"]

: Fleishman, G. D., Gary, D. E., Chen, B., Kuroda, N., Yu, S., & Nita, G. M. (2020), Science, 367, 278. [https://ui.adsabs.harvard.edu/abs/2020Sci...367..278F "Decay of the coronal magnetic field can release sufficient energy to power a solar flare"]

: Chen, B., Shen, C., Gary, D. E., Reeves, K. K., Fleishman, G. D., Yu, S., Guo, F., Krucker, S., Lin, J., Nita, G. M., & Kong, X. (2020), Nature Astronomy, 4, 1140. [https://ui.adsabs.harvard.edu/abs/2020NatAs...4.1140C "Measurement of magnetic field and relativistic electrons along a solar flare current sheet"]

: Lee, J. (2018), Journal of Astronomy and Space Sciences, 35, 211. [https://ui.adsabs.harvard.edu/abs/2018JASS...35..211L "Analysis of Solar Microwave Burst Spectrum, I. Nonuniform Magnetic Field"]

: Gary, D. E., Bastian, T. S., Chen, B., Fleishman, G. D., & Glesener, L. (2018), Science with a Next Generation Very Large Array, 517, 99. [https://ui.adsabs.harvard.edu/abs/2018ASPC..517...99G "Radio Observations of Solar Flares"]

: Polito, V., Dudík, J., Kašparová, J., Dzifčáková, E., Reeves, K. K., Testa, P., & Chen, B. (2018), The Astrophysical Journal, 864, 63. [https://ui.adsabs.harvard.edu/abs/2018ApJ...864...63P "Broad Non-Gaussian Fe XXIV Line Profiles in the Impulsive Phase of the 2017 September 10 X8.3-class Flare Observed by Hinode/EIS"]

: Gary, D. E., Chen, B., Dennis, B. R., Fleishman, G. D., Hurford, G. J., Krucker, S., McTiernan, J. M., Nita, G. M., Shih, A. Y., White, S. M., & Yu, S. (2018), The Astrophysical Journal, 863, 83. [https://ui.adsabs.harvard.edu/abs/2018ApJ...863...83G "Microwave and Hard X-Ray Observations of the 2017 September 10 Solar Limb Flare"]

: Fleishman, G. D., Nita, G. M., Kuroda, N., Jia, S., Tong, K., Wen, R. R., & Zhizhuo, Z. (2018), The Astrophysical Journal, 859, 17. [https://ui.adsabs.harvard.edu/abs/2018ApJ...859...17F "Revealing the Evolution of Non-thermal Electrons in Solar Flares Using 3D Modeling"]

: Kuroda, N., Gary, D. E., Wang, H., Fleishman, G. D., Nita, G. M., & Jing, J. (2018), The Astrophysical Journal, 852, 32. [https://ui.adsabs.harvard.edu/abs/2018ApJ...852...32K "Three-dimensional Forward-fit Modeling of the Hard X-Ray and Microwave Emissions of the 2015 June 22 M6.5 Flare"]

: Wang, H., Liu, C., Ahn, K., Xu, Y., Jing, J., Deng, N., Huang, N., Liu, R., Kusano, K., Fleishman, G. D., Gary, D. E., & Cao, W. (2017), Nature Astronomy, 1, 0085. [https://ui.adsabs.harvard.edu/abs/2017NatAs...1E..85W "High-resolution observations of flare precursors in the low solar atmosphere"]

: Nita, G. M., Hickish, J., MacMahon, D., & Gary, D. E. (2016), Journal of Astronomical Instrumentation, 5, 1641009-7366. [https://ui.adsabs.harvard.edu/abs/2016JAI.....541009N "EOVSA Implementation of a Spectral Kurtosis Correlator for Transient Detection and Classification"]

: Nita, G. M., & Gary, D. E. (2016), Journal of Geophysical Research (Space Physics), 121, 7353. [https://ui.adsabs.harvard.edu/abs/2016JGRA..121.7353N "Measurement of duration and signal-to-noise ratio of astronomical transients using a Spectral Kurtosis spectrometer"]

: Wang, Z., Gary, D. E., Fleishman, G. D., & White, S. M. (2015), The Astrophysical Journal, 805, 93. [https://ui.adsabs.harvard.edu/abs/2015ApJ...805...93W "Coronal Magnetography of a Simulated Solar Active Region from Microwave Imaging Spectropolarimetry"]

: Gary, D. E., Fleishman, G. D., & Nita, G. M. (2013), Solar Physics, 288, 549. [https://ui.adsabs.harvard.edu/abs/2013SoPh..288..549G "Magnetography of Solar Flaring Loops with Microwave Imaging Spectropolarimetry"]

== VLA Flare List and Publications ==
See [http://www.ovsa.njit.edu/wiki/index.php/VLA_Data_Survey#List_of_Jansky_VLA_Solar_Observations this link] for a list of flare observations made by the [https://science.nrao.edu/facilities/vla/ Karl G. Jansky Very Large Array] (VLA). Below is a partial list of publications that utilize VLA solar data (see also [https://ui.adsabs.harvard.edu/public-libraries/ZwbjpLo9RS-viufWEoQ95Q this NASA/ADS Library]).
* [https://ui.adsabs.harvard.edu/abs/2022ApJ...940..137L/abstract Luo et al. (2022), ApJ, 940, 137] ''Multiple Regions of Nonthermal Quasiperiodic Pulsations during the Impulsive Phase of a Solar Flare''
* [https://ui.adsabs.harvard.edu/abs/2021ApJ...922..134B/abstract Battaglia et al. (2021), ApJ, 922, 134] ''Multiple Electron Acceleration Instances during a Series of Solar Microflares Observed Simultaneously at X-Rays and Microwaves''
* [https://ui.adsabs.harvard.edu/abs/2021ApJ...911....4L/abstract Luo et al. (2021), ApJ, 911, 4] ''Radio Spectral Imaging of an M8.4 Eruptive Solar Flare: Possible Evidence of a Termination Shock''
* [https://ui.adsabs.harvard.edu/abs/2021ApJ...910...40Z/abstract Zhang et al. (2021), ApJ, 910, 40] ''Multiwavelength Observations of the Formation and Eruption of a Complex Filament''
* [https://ui.adsabs.harvard.edu/abs/2020ApJ...904...94S/abstract Sharma et al. (2020), ApJ, 904, 94] ''Radio and X-Ray Observations of Short-lived Episodes of Electron Acceleration in a Solar Microflare''
* [https://ui.adsabs.harvard.edu/abs/2019ApJ...884...63C/abstract Chen et al. (2019), ApJ, 884, 63] ''Radio Spectroscopic Imaging of a Solar Flare Termination Shock: Split-band Feature as Evidence for Shock Compression''
* [https://ui.adsabs.harvard.edu/abs/2019ApJ...872...71Y/abstract Yu & Chen (2019), ApJ, 872, 71] ''Possible Detection of Subsecond-period Propagating Magnetohydrodynamics Waves in Post-reconnection Magnetic Loops during a Two-ribbon Solar Flare''
* [https://ui.adsabs.harvard.edu/abs/2018ApJ...866...62C/abstract Chen et al. (2018), ApJ, 866, 62] ''Magnetic Reconnection Null Points as the Origin of Semirelativistic Electron Beams in a Solar Jet
''
* [https://ui.adsabs.harvard.edu/abs/2017ApJ...848...77W/abstract Wang et al. (2016), ApJ, 848, 77] ''Dynamic Spectral Imaging of Decimetric Fiber Bursts in an Eruptive Solar Flare''
* [https://ui.adsabs.harvard.edu/abs/2015Sci...350.1238C/abstract Chen et al. (2015), Science, 350, 1238] ''Particle acceleration by a solar flare termination shock''
* [https://ui.adsabs.harvard.edu/abs/2014ApJ...794..149C/abstract Chen et al. (2014), ApJ, 794, 149] ''Direct Evidence of an Eruptive, Filament-hosting Magnetic Flux Rope Leading to a Fast Solar Coronal Mass Ejection''
* [https://ui.adsabs.harvard.edu/abs/2013ApJ...763L..21C/abstract Chen et al. (2013), ApJL, 763, 21] ''Tracing Electron Beams in the Sun's Corona with Radio Dynamic Imaging Spectroscopy''

==Radio Data from Around The Heliosphere==
* [http://ovsa.njit.edu//wiki/index.php/Radio_Data_from_Around_the_World#Radio_Data_Access '' Radio Data '']

=OVRO-LWA Solar-Dedicated Spectroscopic Imager=
The OVRO-LWA (Owens Valley Radio Observatory Long Wavelength Array) has recently been upgraded to include a solar-dedicated beam and two solar imaging modes (slow visibilities of 352 antennas with a 10-s cadence, and fast visibilities of 48 antennas with a 0.1-s cadence). The large collecting area and excellent calibration provide unprecedented high-sensitivity imaging of the quiet Sun and bursts. The array is currently in commissioning and observations are not yet continuous, but they are becoming more so. See the daily realtime data at http://ovsa.njit.edu/status.php for '''real-time display of the spectrogram and a selection of images''', both updated on a 1-min cadence.

==Solar-Dedicated Modes==
===Beamformer===
The beamformer uses the 256 core antennas to form a synthesized beam of more than 1 degree in size that tracks the Sun from sunrise to sunset. This permits a continuous record of the full-Stokes total flux (without spatial resolution) of the Sun (a dynamic spectrum) with 24 kHz frequency resolution (3072 frequencies from 15-90 MHz) and as low as 1 ms time resolution.

===Slow Visibility Imaging===
In this mode, the entire 352-element array is interferometrically correlated to provide visibilities for imaging at all 3072 frequencies at 10-s time resolution. This is ideal for imaging quiet Sun and slowly-varying emission such as coronal mass ejections and active region variability.

===Fast Visibility Imaging===
In this mode, a subset of 48 antennas (chosen to include mainly outer antennas to maintain good spatial resolution) is interferometrically correlated to provide visibilities for imaging at 768 frequencies (96 kHz frequency resolution) at 0.1-s time resolution. This is ideal for imaging rapidly varying emission such as type II and type III bursts as well as many other solar spectral fine structures.

==Inital Data Access==
In its current commissioning state, we try to run the beamformer and imaging pipeline every day in real-time since November 2023 (no latency for beamforming spectrograms and 5-10 min latency for images). Quicklook real-time spectrograms/images can be accessed from http://ovsa.njit.edu/status.php. To access data from previous days, use the following links (replace yyyymmdd with the date you desire):
* Quicklook beamformer total-power spectrograms: http://ovsa.njit.edu/lwa-data/1min_spectra/yyyymmdd/. Check this link for additional daily plots [[Daily OVRO-LWA Beamformer Data]].
* Quicklook multi-frequency movies at 1-min cadence: http://ovsa.njit.edu/lwa-data/1min_images/yyyymmdd/movie_yyyy-mm-dd.html

Note our pipeline processing development is still in the early phase. For example, absolute flux calibrations have not been done for the beamformer spectrograms. Also, artificial effects (including ionospheric refraction effects) are present in the images that cause distortions/shifts. We caution interested users only to consider them for quick-look purposes at this point. Please contact the EOVSA PIs (Dale Gary, Bin Chen) if you intend to use them for science.

== OVRO-LWA Observing Log ==
[https://docs.google.com/document/d/1QDWw5y4HpcE7CSpzXwftMqQT4FDgNJj-6fRrgWrqdug/edit?usp=sharing Link to the OVRO-LWA solar observing logs (in Google Doc)]

File:EOVSA 20240210 M9flare.png

2024-02-11T17:58:43Z

Dgary:

Recent Flare List (2021-)

2024-02-11T17:58:04Z

Dgary: /* February 2024 */

== List of EOVSA Flares with Spectrogram Data ==
===Pre-2021 Selected Events===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || EOVSA Images || Comment
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2019-04-15 2019-04-15] || 19:31 || B3.3 || [[File:EOVSA_20190415_B3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20190415_B3flare.dat plot data] || NA || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20190415_192700 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2019/04/15/eovsa.lev1_mbd_12s.flare_id_20190415193100.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2019/04/15/20190415193100/ FITS Files] ||
|}

===April 2021===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || EOVSA Images || Comment
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-04-17 2021-04-17] || 16:46 || B9.0 || [[File:EOVSA_20210417_B9flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210417_B9flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1618675803&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210417_162100 AIA] || ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-04-19 2021-04-19] || 23:36 || M1.0 || [[File:EOVSA_20210419_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210419_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1618873203&span=1264 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210419_231900 AIA] ||
|}

===May 2021===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || EOVSA Images || Comment
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-05-05 2021-05-05] || 22:30 || B5.0 || [[File:EOVSA_20210505_B1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210505_B1flare.dat plot data] || [https://pub023.cs.technik.fhnw.ch/wiki/index.php?title=STIX_Flare:_2105052229 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210505_222500 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/05/05/eovsa.lev1_mbd_12s.flare_id_20210505223000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/05/05/20210505223000/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-05-07 2021-05-07] || 19:00 || M4.0 || [[File:EOVSA_20210507_M4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210507_M4flare.dat plot data] || [https://pub023.cs.technik.fhnw.ch/wiki/index.php?title=STIX_Flare:_2105071900 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210507_184300 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/05/07/eovsa.lev1_mbd_12s.flare_id_20210507190000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/05/07/20210507190000/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-05-08 2021-05-08] || 18:30 || C9.0 || [[File:EOVSA_20210508_C9flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210508_C9flare.dat plot data] || [https://pub023.cs.technik.fhnw.ch/view/plot/lightcurves?start=1620498000.242&span=3500 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210508_182200 AIA] || ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-05-09 2021-05-09] || 13:55 || C4.0 || [[File:EOVSA_20210509_C4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210509_C4flare.dat plot data] || [https://pub023.cs.technik.fhnw.ch/wiki/index.php?title=STIX_Flare:_2105091355 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210509_133800 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/05/09/eovsa.lev1_mbd_12s.flare_id_20210509135500.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/05/09/20210509135500/ FITS Files] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-05-17 2021-05-17] || 19:05 || B5.0 || [[File:EOVSA_20210517_B5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210517_B5flare.dat plot data] || [https://pub023.cs.technik.fhnw.ch/wiki/index.php?title=STIX_Flare:_2105171905 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210517_190000 AIA] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-05-21 2021-05-21] || 19:25 || C5.0 || [[File:EOVSA_20210521_C5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210521_C5flare.dat plot data] || [https://pub023.cs.technik.fhnw.ch/wiki/index.php?title=STIX_Flare:_2105211927 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210521_191500 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/05/21/eovsa.lev1_mbd_12s.flare_id_20210521192500.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/05/21/20210521192500/ FITS Files] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-05-22 2021-05-22] || 16:10 || C1.0 || [[File:EOVSA_20210522_C1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210522_C1flare.dat plot data] || [https://pub023.cs.technik.fhnw.ch/wiki/index.php?title=STIX_Flare:_2105221616 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210522_160300 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/05/22/eovsa.lev1_mbd_12s.flare_id_20210522161000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/05/22/20210522161000/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-05-22 2021-05-22] || 17:10 || M1.0 || [[File:EOVSA20210522_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210522_M1flare.dat plot data] || [https://pub023.cs.technik.fhnw.ch/wiki/index.php?title=STIX_Flare:_2105221710 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210522_170300 AIA] || ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-05-22 2021-05-22] || 21:30 || M1.4 || [[File:EOVSA_20210522_M1.4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210522_M1.4flare.dat plot data] || [https://pub023.cs.technik.fhnw.ch/wiki/index.php?title=STIX_Flare:_2105222135 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210522_210800 AIA] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-05-22 2021-05-22] || 23:11 || C7.0 || [[File:EOVSA_20210522_C7flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210522_C7flare.dat plot data] || [https://pub023.cs.technik.fhnw.ch/wiki/index.php?title=STIX_Flare:_2105222311 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210522_230500 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/05/22/eovsa.lev1_mbd_12s.flare_id_20210522231100.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/05/22/20210522231100/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-05-23 2021-05-23] || 17:00 || C2.0 || [[File:EOVSA_20210523_C2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210523_C2flare.dat plot data] || [https://pub023.cs.technik.fhnw.ch/wiki/index.php?title=STIX_Flare:_2105231704 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://aia.lmsal.com/ER_EruptionCharacterize_20210523_1658_15_377 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/05/23/eovsa.lev1_mbd_12s.flare_id_20210523170000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/05/23/20210523170000/ FITS Files] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-05-27 2021-05-27] || 22:00 || C1.0 || [[File:EOVSA_20210527_C1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210527_C1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1622151002&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helioinformatics.org/ER_AIA_193_NariakiNitta_20210701_200257 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/05/27/eovsa.lev1_mbd_12s.flare_id_20210527220000.mp4 Quicklook Movie] [FITS Files] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-05-27 2021-05-27] || 23:10 || C7.0 || [[File:EOVSA_20210527_C7flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210527_C7flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1622156402&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_FlareDetective-TriggerModule_20210528_050926_2021-05-27T23:01:32.073_1 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/05/27/eovsa.lev1_mbd_12s.flare_id_20210527231000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/05/27/20210527231000/ FITS Files] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-05-28 2021-05-28] || 22:30 || C9.0 || [[File:EOVSA_20210528_C9flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210528_C9flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1622239203&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_FlareDetective-TriggerModule_20210528_231341_2021-05-28T22:29:20.066_1 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/05/28/eovsa.lev1_mbd_12s.flare_id_20210528223000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/05/28/20210528223000/ FITS Files] ||
|}

===July 2021===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || EOVSA Images || Comment
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-07-03 2021-07-03] || 14:27 || X1.5 || [[File:EOVSA_20210703_X1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210703_X1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1625320800&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210703_141800 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/07/03/eovsa.lev1_mbd_12s.flare_id_20210703142700.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/07/03/20210703142700/ FITS Files] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-07-06 2021-07-06] || 19:15 || C1.1 || [[File:EOVSA_20210706_flare1.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210706_flare1.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1625598000&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210706_190600 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/07/06/eovsa.lev1_mbd_12s.flare_id_20210706191500.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/07/06/20210706191500/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-07-06 2021-07-06] || 20:58 || C1.2 || [[File:EOVSA_20210706_flare2.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210706_flare2.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1625603400&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210706_205300 AIA] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-07-06 2021-07-06] || 21:49 || C1.1 || [[File:EOVSA_20210706_flare3.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210706_flare3.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1625607000&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210706_214400 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/07/06/eovsa.lev1_mbd_12s.flare_id_20210706214900.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/07/06/20210706214900/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-07-09 2021-07-09] || 17:20 || C4.7 || [[File:EOVSA_20210709_C4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210709_C4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1625850000&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210709_171500 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/07/09/eovsa.lev1_mbd_12s.flare_id_20210709172000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/07/09/20210709172000/ FITS Files]
|}

===August 2021===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || EOVSA Images || Comment
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-08-20 2021-08-20] || 15:55 || C3.0 || [[File:EOVSA_20210820_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210820_C3flare.dat plot data] || [https://pub023.cs.technik.fhnw.ch/view/plot/lightcurves?start=1629473625&span=2140 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210820_155000 AIA] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-08-20 2021-08-20] || 21:45 || C1.4 || [[File:EOVSA_20210820_C1.4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210820_C1.4flare.dat plot data] ||[https://pub023.cs.technik.fhnw.ch/view/plot/lightcurves?start=1629494754&span=2980 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210820_213000 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/08/20/eovsa.lev1_mbd_12s.flare_id_20210820214500.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/08/20/20210820214500/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-08-21 2021-08-21] || 18:41 || B3.9 || [[File:EOVSA_20210821_B3.9flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210821_B3.9flare.dat plot data] || [https://pub023.cs.technik.fhnw.ch/view/plot/lightcurves?start=1629473625&span=2140 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210821_183700 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/08/21/eovsa.lev1_mbd_12s.flare_id_20210821184100.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/08/21/20210821184100/ FITS Files] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-08-21 2021-08-21] || 21:57 || B3.9 || [[File:EOVSA_20210821_B3.9flare2.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210821_B3.9flare2.dat plot data] || [https://pub023.cs.technik.fhnw.ch/view/plot/lightcurves?start=1629473625&span=2140 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210821_215700 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/08/21/eovsa.lev1_mbd_12s.flare_id_20210821215700.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/08/21/20210821215700/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-08-21 2021-08-21] || 22:29 || B4.7 || [[File:EOVSA_20210821_B4.7flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210821_B4.7flare.dat plot data] || [https://pub023.cs.technik.fhnw.ch/view/plot/lightcurves?start=1629473625&span=2140 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210821_221100 AIA] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-08-26 2021-08-26] || 18:12 || C3.0 || [[File:EOVSA_20210826_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210826_C3flare.dat plot data] || [https://pub023.cs.technik.fhnw.ch/view/plot/lightcurves?start=1629999900&span=5000 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210826_174800 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/08/26/eovsa.lev1_mbd_12s.flare_id_20210826181200.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/08/26/20210826181200/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-08-26 2021-08-26] || 23:20 || C3.9 || [[File:EOVSA_20210826_C3.9flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210826_C3.9flare.dat plot data] || [https://pub023.cs.technik.fhnw.ch/view/plot/lightcurves?start=1630019400&span=2400 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210826_231700 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/08/26/eovsa.lev1_mbd_12s.flare_id_20210826232000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/08/26/20210826232000/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-08-27 2021-08-27] || 21:00 || C7.3 || [[File:EOVSA_20210827_C7flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210827_C7flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1630096200&span=3595 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210827_203200 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/08/27/eovsa.lev1_mbd_12s.flare_id_20210827210000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/08/27/20210827210000/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-08-29 2021-08-29] || 17:21 || C2.9 || [[File:EOVSA_20210829_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210829_C3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1630256400&span=3596 Yes (occulted?)] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210829_170100 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/08/29/eovsa.lev1_mbd_12s.flare_id_20210829172100.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/08/29/20210829172100/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-08-30 2021-08-30] || 16:12 || C2.0 || [[File:EOVSA_20210830_C2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210830_C2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1630339200&span=3596 Yes (occulted)] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210830_162000 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/08/30/eovsa.lev1_mbd_12s.flare_id_20210830161200.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/08/30/20210830161200/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-08-30 2021-08-30] || 18:23 || B7.0 || [[File:EOVSA_20210830_B7flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210830_B7flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1630346400&span=3596 Yes (occulted)] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210830_181700 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/08/30/eovsa.lev1_mbd_12s.flare_id_20210830182300.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/08/30/20210830182300/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-08-30 2021-08-30] || 20:47 || B8.0 || [[File:EOVSA_20210830_B8flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210830_B8flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1630353600&span=3596 Yes (occulted)] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210830_204400 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/08/30/eovsa.lev1_mbd_12s.flare_id_20210830204700.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/08/30/20210830204700/ FITS Files] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-08-31 2021-08-31] || 14:48 || B2.5 || [[File:EOVSA_20210831_Bflares.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210831_Bflares.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1630418403&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210831_145400 AIA] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-08-31 2021-08-31] || 19:08 || B7.1 || [[File:EOVSA_20210831_B7flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210831_B7flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1630436403&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210831_185700 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/08/31/eovsa.lev1_mbd_12s.flare_id_20210831190800.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/08/31/20210831190800/ FITS Files]
|}

===September 2021===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || EOVSA Images || Comment
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-09-08 2021-09-08] || 17:24 || C8.3 || [[File:EOVSA_20210908_C8flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210908_C8flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1631120401&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210908_171100 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/09/08/eovsa.lev1_mbd_12s.flare_id_20210908172400.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/09/08/20210908172400/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-09-20 2021-09-20] || 19:24 || B4.0 || [[File:EOVSA_20210920_flares0.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210920_flares0.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1632164400&span=10795 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210920_191700 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/09/20/eovsa.lev1_mbd_12s.flare_id_20210920192400.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/09/20/20210920192400/ FITS Files] ||

|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-09-20 2021-09-20] || 21:00 || B2.5 || [[File:EOVSA_20210920_flares1.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210920_flares1.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1632164400&span=10795 Yes] ||[https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210920_205500 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/09/20/eovsa.lev1_mbd_12s.flare_id_20210920210000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/09/20/20210920210000/ FITS Files] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-09-20 2021-09-20] || 21:52 || B3.3 ||[[File:EOVSA_20210920_flares2.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210920_flares2.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1632164400&span=10795 Yes] ||[https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210920_213700 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/09/20/eovsa.lev1_mbd_12s.flare_id_20210920215200.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/09/20/20210920215200/ FITS Files] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-09-21 2021-09-21] || 20:24 || B5.1 || [[File:EOVSA_20210921_Bflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210921_Bflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1632254400&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210921_201500 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/09/21/eovsa.lev1_mbd_12s.flare_id_20210921202400.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/09/21/20210921202400/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-09-22 2021-09-22] || 20:12 || C1.1 || [[File:EOVSA_20210922_Cflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210922_Cflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1632340800&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210922_200400 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/09/22/eovsa.lev1_mbd_12s.flare_id_20210922201200.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/09/22/20210922201200/ FITS Files] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-09-23 2021-09-23] || 15:24 || M1.9 || [[File:EOVSA_20210923_M2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210923_M2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1632409200&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210923_152300 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/09/23/eovsa.lev1_mbd_12s.flare_id_20210923152400.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/09/23/20210923152400/ FITS Files] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-09-23 2021-09-23] || 20:40 || C1.0 || [[File:EOVSA_20210923_Cflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210923_Cflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1632427200&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210923_203400 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/09/23/eovsa.lev1_mbd_12s.flare_id_20210923204000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/09/23/20210923204000/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-09-24 2021-09-24] || 16:45 || none? B4.0 at 16:12 || [[File:EOVSA_20210924_Bflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210924_Bflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1632499200&span=3596 No?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210924_161200 AIA?] || ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-09-24 2021-09-24] || 21:16 || B2.0 || [[File:EOVSA_20210924_Bflares.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210924_Bflares.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1632517200&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210924_211100 AIA] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-09-25 2021-09-25] || 19:15 || C1.7 || [[File:EOVSA_20210925_Cflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20210925_Cflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1632596400&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20210925_191100 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/09/25/eovsa.lev1_mbd_12s.flare_id_20210925191500.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/09/25/20210925191500/ FITS Files] ||
|}

===October 2021===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || EOVSA Images || Comment
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-10-11 2021-10-11] || 19:21 || B2 || [[File:EOVSA_20211011_Bflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20211011_Bflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1633978803&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20211011_192300 AIA] || || [[File:EOVSA20211011_1924_10-pct_contours.png|thumb|center|100px|(EOVSA 10% contours)]]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-10-12 2021-10-12] || 15:57 || B6 || [[File:EOVSA_20211012_Bflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20211012_Bflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1634052600&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20211012_155400 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/10/12/eovsa.lev1_mbd_12s.flare_id_20211012155700.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/10/12/20211012155700/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-10-28 2021-10-28] || 15:26 || X1 || [[File:EOVSA_20211028_Xflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20211028_Xflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1635433203&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20211028_151700 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/10/28/eovsa.lev1_mbd_12s.flare_id_20211028152600.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/10/28/20211028152600/ FITS Files] || Evidence for low band spike emission [[File:EOVSA_20211028_spikes.png|thumb|center|100px|]] (~15:28:30 UT); obs by PSP/RFS
|}

===November 2021===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || EOVSA Images || Comment
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-11-01 2021-11-01] || 20:43 || C2.1 || [[File:EOVSA_20211101_C2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20211101_C2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1635796802&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_FlareDetective-TriggerModule_20211103_151302_2021-11-01T20:41:32.066_1 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/11/01/eovsa.lev1_mbd_12s.flare_id_20211101204300.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/11/01/20211101204300/ FITS Files] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-11-01 2021-11-01] || 21:11 || C4.0 || [[File:EOVSA_20211101_C4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20211101_C4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1635800402&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_FlareDetective-TriggerModule_20211103_151313_2021-11-01T20:49:56.081_1 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/11/01/eovsa.lev1_mbd_12s.flare_id_20211101211100.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/11/01/20211101211100/ FITS Files] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-11-01 2021-11-01] || 23:39 || C4.5 || [[File:EOVSA_20211101_C4.5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20211101_C4.5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1635807602&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_FlareDetective-TriggerModule_20211103_175852_2021-11-01T23:37:34.342_1 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/11/01/eovsa.lev1_mbd_12s.flare_id_20211101233900.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/11/01/20211101233900/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-11-03 2021-11-03] || 21:14 || C5.2 || [[File:EOVSA_20211103_C5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20211103_C5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1635973203&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20211103_144904_276 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/11/03/eovsa.lev1_mbd_12s.flare_id_20211103211400.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/11/03/20211103211400/ FITS Files]
|}

===December 2021===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || EOVSA Images || Comment
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-12-12 2021-12-12] || 21:13 || C1.2 || [[File:EOVSA_20211212_Cflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20211212_Cflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1639342800&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20211212_134053_056 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/12/12/eovsa.lev1_mbd_12s.flare_id_20211212211300.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/12/12/20211212211300/ FITS Files] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-12-14 2021-12-14] || 20:33 || C1.6 || [[File:EOVSA_20211214_Cflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20211214_Cflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1639512000&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20211214_135535_901 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/12/14/eovsa.lev1_mbd_12s.flare_id_20211214203300.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/12/14/20211214203300/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2021-12-31 2021-12-31] || 19:42 || C8.1 || [[File:EOVSA_20211232_C8flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2021/EOVSA_20211231_C8flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1640977200&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20211231_121920_408 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2021/12/31/eovsa.lev1_mbd_12s.flare_id_20211231194200.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2021/12/31/20211231194200/ FITS Files] || Surprisingly weak in microwaves considering it is a C8 in soft X-rays.
|}

===January 2022===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || EOVSA Images || Comment
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-01-18 2022-01-18] || 17:38 || M1.2 || [[File:EOVSA_20220118_Mflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220118_Mflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1642525200&span=5999 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220118_100506_860 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/01/18/eovsa.lev1_mbd_12s.flare_id_20220118173800.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/01/18/20220118173800/ FITS Files] || Type III at ~17:45 by PSP/RFS/LFR
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-01-28 2022-01-28] || 19:31 || C2.8 || [[File:EOVSA_20220128_C2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220128_C2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1643397600&span=7196 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220128_192200 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/01/28/eovsa.lev1_mbd_12s.flare_id_20220128193100.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/01/28/20220128193100/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-01-28 2022-01-28] || 20:35 || B5.3 || [[File:EOVSA_20220128_Bflares.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220128_Bflares.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1643397600&span=7196 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220128_202700 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/01/28/eovsa.lev1_mbd_12s.flare_id_20220128203500.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/01/28/20220128203500/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-01-28 2022-01-28] || 20:49 || B6.5 || [[File:EOVSA_20220128_Bflares.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220128_Bflares.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1643397600&span=7196 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220128_204200 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/01/28/eovsa.lev1_mbd_12s.flare_id_20220128204900.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/01/28/20220128204900/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-01-29 2022-01-29] || 23:00 || M1 || [[File:EOVSA_20220129_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220129_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1643493600&span=10796 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220129_223200 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/01/29/eovsa.lev1_mbd_12s.flare_id_20220129230000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/01/29/20220129230000/ FITS Files] || EOVSA took fast-mode data of this event [[File:EOVSA_20220129_fast_mode.png|thumb|center|100px|]] Each row is 2-min of data at 20 ms cadence
|}

===February 2022===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || EOVSA Images || Comment
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-02-03 2022-02-03] || 20:42 || C1.3 || [[File:EOVSA_20220203_C1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220203_C1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1643920200&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220203_155917_799 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/02/03/eovsa.lev1_mbd_12s.flare_id_20220203204200.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/02/03/20220203204200/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-02-05 2022-02-05] || 17:00 || C2.1 || [[File:EOVSA_20220205_C2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220205_C2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1644079800&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220205_094036_781 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/02/05/eovsa.lev1_mbd_12s.flare_id_20220205170000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/02/05/20220205170000/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-02-08 2022-02-08] || 21:40 || C5.1 || [[File:EOVSA_20220208_C5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220208_C5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1644355200&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220208_212900 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/02/08/eovsa.lev1_mbd_12s.flare_id_20220208214000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/02/08/20220208214000/ FITS Files]
|}

===March 2022===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || EOVSA Images || Comment
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-03-30 2022-03-30] || 17:30 || X1.4 || [[File:EOVSA_20220330_Xflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220330_Xflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1648659603&span=7192 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220330_172100 AIA] || || [[File:EOVSA_20220330_Xflare_osc.png|thumb|center|100px|]] Interesting oscillations
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-03-31 2022-03-31] || 18:28 || M9.7 || [[File:EOVSA_20220331_M9flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220331_M9flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1648749600&span=7196 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220331_120048_950 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/03/31/eovsa.lev1_mbd_12s.flare_id_20220331182800.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/03/31/20220331182800/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-03-31 2022-03-31] || 19:32 || C5 || [[File:EOVSA_20220331_Cflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220331_Cflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1648749600&span=7196 No(occulted)] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220331_125952_709 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/03/31/eovsa.lev1_mbd_12s.flare_id_20220331193200.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/03/31/20220331193200/ FITS Files]
|}

===April 2022===
'''Although EOVSA observed many interesting events in April, the cooled receiver on the 27-m antenna, essential for phase calibration, was not working from about April 1 - May 7, 2022. The cause of the long outage was that the manlift needed to repair the receiver had a flat tire that required a long leadtime to replace. Any events seen during this period are available in total power only--no imaging is possible.'''

===May 2022===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || EOVSA Images || Comment
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-05-10 2022-05-10] || 13:55 || X1.5 || [[File:EOVSA_20220510_Xflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220510_Xflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1652189400&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220510_071433_010 AIA] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-05-11 2022-05-11] || 18:35 || M2.6 || [[File:EOVSA_20220511_M2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220511_M2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1652292003&span=10796 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220511_181300 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/05/11/eovsa.lev1_mbd_12s.flare_id_20220511183500.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/05/11/20220511183500/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-05-14 2022-05-15] || 00:01 || M2.3 || [[File:EOVSA_20220515_M2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220515_M2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1652571003&span=3596 No(occulted)] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220514_172903_425 AIA] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-05-17 2022-05-17] || 19:33 || C2.0 || [[File:EOVSA_20220517_C2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220517_C2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1652814003&span=3595 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220517_192900 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/05/17/eovsa.lev1_mbd_12s.flare_id_20220517193300.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/05/17/20220517193300/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-05-18 2022-05-18] || 22:00 || M1.1 || [[File:EOVSA_20220518_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220517_C2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1652909403&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220518_215600 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/05/18/eovsa.lev1_mbd_12s.flare_id_20220518220000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/05/18/20220518220000/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-05-24 2022-05-24] || 22:30 || C5.1 || [[File:EOVSA_20220524_C2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220524_C2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1653431400&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_FlareDetective-TriggerModule_20220525_091313_2022-05-24T22:13:41.843_1 AIA?]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-05-25 2022-05-25] || 18:17 || M1.3 || [[File:EOVSA_20220525_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220525_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1653501600&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220525_115412_323 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/05/25/eovsa.lev1_mbd_12s.flare_id_20220525181700.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/05/25/20220525181700/ FITS Files] || Two-ribbon flare from spotless region
|}

===July 2022===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || EOVSA Images || Comment
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-07-08 2022-07-08] || 20:23 || M2.6 || [[File:EOVSA_20220708_Mflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220708_Mflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1657310400&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220708_200700 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/07/08/eovsa.lev1_mbd_12s.flare_id_20220708202300.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/07/08/20220708202300/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-07-14 2022-07-14] || 21:45 || M2.9 || [[File:EOVSA_20220714_Mflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220714_Mflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1657832400&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220714_150353_832 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/07/14/eovsa.lev1_mbd_12s.flare_id_20220714214500.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/07/14/20220714214500/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-07-15 2022-07-15] || 23:09 || C2.9 || [[File:EOVSA_20220715_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220715_C3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1657926000&span=3595 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220715_162845_112 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/07/15/eovsa.lev1_mbd_12s.flare_id_20220715230900.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/07/15/20220715230900/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-07-16 2022-07-16] || 22:17 || C2.0 || [[File:EOVSA_20220716_C1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220716_C1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1658091600&span=3596# yes (occulted?)] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220716_231936_053 AIA] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-07-17 2022-07-17] || 21:37 || C4.8 || [[File:EOVSA_20220717_C4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220717_C4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1658091600&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220717_213000 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/07/17/eovsa.lev1_mbd_12s.flare_id_20220717213700.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/07/17/20220717213700/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-07-31 2022-07-31] || 22:50 || C9.3 || [[File:EOVSA_20220731_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220731_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1659304800&span=7196 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220731_165602_411 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/07/31/eovsa.lev1_mbd_12s.flare_id_20220731225000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/07/31/20220731225000/ FITS Files]
|}

===August 2022===
Note: For much of August the array was down due to a planned power outage to install some new power equipment. The event on 2022 Aug. 30 was observed while the array was not yet tuned for delays.
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || EOVSA Images || Comment
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-08-30 2022-08-30] || 17:58 || M1.2 || [[File:EOVSA_20220830_M2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220830_M2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1661878803&span=7196 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220830_173500 AIA?] || || The amplitudes are not corrected for bad delays
[http://ovsa.njit.edu/events/2022/EOVSA_20220830_M2flare_TP.png link to total power plot with ~ correct amplitudes]
|}

===September 2022===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || EOVSA Images || Comment
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-09-12 2022-09-12] || 23:45 || M1.8 || [[File:EOVSA_20220912_M2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220912_M2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1663023603&span=7192 Yes (occulted)] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220912_233700 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/09/12/eovsa.lev1_mbd_12s.flare_id_20220912234500.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/09/12/20220912234500/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-09-16 2022-09-16] || 15:51 || M6.7 || [[File:EOVSA_20220916_M6flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220916_M6flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1663340403&span=7195 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220916_154900 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/09/16/eovsa.lev1_mbd_12s.flare_id_20220916155100.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/09/16/20220916155100/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-09-17 2022-09-17] || 20:43 || M2.6 || [[File:EOVSA_20220917_M2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220917_M2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1663340403&span=7195 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220917_140313_689 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/09/17/eovsa.lev1_mbd_12s.flare_id_20220917204300.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/09/17/20220917204300/ FITS Files] || Weak, occulted event
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-09-18 2022-09-18] || 22:11 || C3.0 || [[File:EOVSA_20220918_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220918_C3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1663537800&span=3596 No(occulted)] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220918_212200 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/09/18/eovsa.lev1_mbd_12s.flare_id_20220918221100.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/09/18/20220918221100/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-09-23 2022-09-23] || 18:02 || M1.7 || [[File:EOVSA_20220923_M2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220923_M2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1663955402&span=3596 No(occulted)] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220923_112335_231 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/09/23/eovsa.lev1_mbd_12s.flare_id_20220923180200.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/09/23/20220923180200/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-09-30 2022-09-30] || 16:24 || M3.0 || [[File:EOVSA_20220930_M3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220930_M3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1664553600&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220930_094307_839 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/09/30/eovsa.lev1_mbd_12s.flare_id_20220930162400.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/09/30/20220930162400/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-09-30 2022-09-30] || 22:41 || C3.0 || [[File:EOVSA_20220930_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20220930_C3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1664575200&span=3596 No?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20220930_155800_393 AIA] || || Nice on-disk jet-like event
|-
|}

===October 2022===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || EOVSA Images || Comment
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-10-01 2022-10-01] || 18:02 || C3 || [[File:EOVSA_20221001_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221001_C3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1664645400&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221001_111826_487 AIA?] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/10/01/eovsa.lev1_mbd_12s.flare_id_20221001180200.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/10/01/20221001180200/ FITS Files] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221001_175800 AIA?]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-10-01 2022-10-01] || 18:49 || C2 || [[File:EOVSA_20221001_C2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221001_C2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1664647200&span=3596 No?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221001_114340_598 AIA?] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/10/01/eovsa.lev1_mbd_12s.flare_id_20221001184900.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/10/01/20221001184900/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-10-01 2022-10-01] || 20:09 || M5.8 || [[File:EOVSA_20221001_M5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221001_M5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1664654400&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221001_132822_250 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/10/01/eovsa.lev1_mbd_12s.flare_id_20221001200900.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/10/01/20221001200900/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-10-02 2022-10-02] || 20:23 || X1.1 || [[File:EOVSA_20221002_X1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221002_X1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1664739000&span=5996 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221002_195300 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/10/02/eovsa.lev1_mbd_12s.flare_id_20221002202300.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/10/02/20221002202300/ FITS Files] || Very strong radio event >1700 sfu.
While STIX detected a flare occurring simultaneously,
it was located near the east limb and not the X1.1 flare in the western hemisphere.
The Solar Orbiter couldn't observe the X1.1 flare due to its positioning.
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-10-03 2022-10-03] || 20:21 || M1.2 || [[File:EOVSA_20221003_M2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221003_M2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1664827200&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221003_140310_462 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/10/03/eovsa.lev1_mbd_12s.flare_id_20221003202100.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/10/03/20221003202100/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-10-10 2022-10-10] || 15:42 || C5 || [[File:EOVSA_20221010_C5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221010_M2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1665414003&span=5996 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221010_153400 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/10/10/eovsa.lev1_mbd_12s.flare_id_20221010154200.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/10/10/20221010154200/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-10-10 2022-10-10] || 16:12 || M2.4 || [[File:EOVSA_20221010_M2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221010_M2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1665414003&span=5996 Yes(occulted?)] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221010_095828_857 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/10/10/eovsa.lev1_mbd_12s.flare_id_20221010161200.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/10/10/20221010161200/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-10-10 2022-10-10] || 23:19 || C3 || [[File:EOVSA_20221010_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221010_C3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1665442803&span=3596 No?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221010_163827_267 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/10/10/eovsa.lev1_mbd_12s.flare_id_20221010231900.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/10/10/20221010231900/ FITS Files] || Tiny circular-ribbon flare
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-10-11 2022-10-11] || 16:35 || C3.6 || [[File:EOVSA_20221011_Cflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221011_Cflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1665504000&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221011_101331_962 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/10/11/eovsa.lev1_mbd_12s.flare_id_20221011163500.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/10/11/20221011163500/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-10-11 2022-10-11] || 18:17 || C6.1 || [[File:EOVSA_20221011_C6flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221011_C6flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1665511200&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221011_113330_340 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/10/11/eovsa.lev1_mbd_12s.flare_id_20221011181700.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/10/11/20221011181700/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-10-12 2022-10-12] || 16:28 || C4.7 || [[File:EOVSA_20221012_C4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221012_C4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1665590400&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221012_162600 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/10/12/eovsa.lev1_mbd_12s.flare_id_20221012162800.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/10/12/20221012162800/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-10-12 2022-10-13] || 00:10 || M1.5 || [[File:EOVSA_20221013_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221013_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1665619200&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221012_174822_719 AIA] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-10-16 2022-10-16] || 16:05 || C1.9 || [[File:EOVSA_20221016_C1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221016_C1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1665936000&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221016_093518_450 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/10/16/eovsa.lev1_mbd_12s.flare_id_20221016160500.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/10/16/20221016160500/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-10-19 2022-10-19] || 21:44 || C4.2 || [[File:EOVSA_20221019_C4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221019_C4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1666213200&span=5996 Yes?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221019_153537_642 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/10/19/eovsa.lev1_mbd_12s.flare_id_20221019214400.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/10/19/20221019214400/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-10-25 2022-10-25] || 19:00 || C4.9 || [[File:EOVSA_20221025_C4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221025_C4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1666720801&span=5996 Yes?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221025_123031_223 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/10/25/eovsa.lev1_mbd_12s.flare_id_20221025190000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/10/25/20221025190000/ FITS Files]
|-
|}

===November 2022===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || EOVSA Images || Comment
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-11-10 2022-11-10] || 18:14 || B9.7 || [[File:EOVSA_20221110_Bflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221110_Bflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1668103180&span=1552 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221110_180900 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/11/10/eovsa.lev1_mbd_12s.flare_id_20221110181400.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/11/10/20221110181400/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-11-12 2022-11-12] || 18:02 || C6.5 || [[File:EOVSA_20221112_Cflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221112_Cflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1668275331&span=1728 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221112_180100 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/11/12/eovsa.lev1_mbd_12s.flare_id_20221112180200.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/11/12/20221112180200/ FITS Files] || Unusually fast (1-s) rise time
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-11-13 2022-11-13] || 19:08 || C2.2 || [[File:EOVSA_20221113_C2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221113_C2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1668366000&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221113_190200 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/11/13/eovsa.lev1_mbd_12s.flare_id_20221113190800.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/11/13/20221113190800/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-11-13 2022-11-13] || 22:15 || C2.0 || [[File:EOVSA_20221113_Cflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221113_Cflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1668376028&span=3232 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221113_143932_065 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/11/13/eovsa.lev1_mbd_12s.flare_id_20221113221500.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/11/13/20221113221500/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-11-14 2022-11-14] || 19:27 || C5.1 || [[File:EOVSA_20221114_C5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221114_C5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1668452164&span=4324 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221114_114417_548 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/11/14/eovsa.lev1_mbd_12s.flare_id_20221114192700.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/11/14/20221114192700/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-11-14 2022-11-14] || 21:24 || C2.6 || [[File:EOVSA_20221114_C2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221114_C2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1668459616&span=2160 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221114_211200 AIA?] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/11/14/eovsa.lev1_mbd_12s.flare_id_20221114212400.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/11/14/20221114212400/ FITS Files] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-11-18 2022-11-18] || 18:54 || C4.6 || [[File:EOVSA_20221118_C4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221118_C4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1668795784&span=5864 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221118_184400 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/11/18/eovsa.lev1_mbd_12s.flare_id_20221118185400.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/11/18/20221118185400/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-11-18 2022-11-18] || 22:04 || C1.9 || [[File:EOVSA_20221118_C1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221118_C1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1668808056&span=1732 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221118_215900 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/11/18/eovsa.lev1_mbd_12s.flare_id_20221118220400.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/11/18/20221118220400/ FITS Files]
|-
|}

===December 2022===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || EOVSA Images || Comment
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-12-09 2022-12-09] || 22:42 || C5.0 || [[File:EOVSA_20221209_Cflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221209_Cflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1670624948&span=2832 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221209_223800 AIA] || || Very spikey, yet strong (and brief) in SXR
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-12-13 2022-12-13] || 19:48 || C1.0 || [[File:EOVSA_20221213_C1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221213_C1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1670957652&span=5252 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221213_194700 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/12/13/eovsa.lev1_mbd_12s.flare_id_20221213194800.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/12/13/20221213194800/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-12-13 2022-12-13] || 23:17 || C3.0 || [[File:EOVSA_20221213_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221213_C3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1670972540&span=3592 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221213_154308_682 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/12/13/eovsa.lev1_mbd_12s.flare_id_20221213231700.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/12/13/20221213231700/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-12-14 2022-12-14] || 19:09 || C3.0 || [[File:EOVSA_20221214_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221214_C3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1671044004&span=1964 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221214_190300 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/12/14/eovsa.lev1_mbd_12s.flare_id_20221214190900.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/12/14/20221214190900/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-12-14 2022-12-14] || 19:33 || C6.4 || [[File:EOVSA_20221214_C5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221214_C5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1671045072&span=3528 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221214_132816_374 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/12/14/eovsa.lev1_mbd_12s.flare_id_20221214193300.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/12/14/20221214193300/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-12-14 2022-12-14] || 20:55 || M2.2 || [[File:EOVSA_20221214_M2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221214_M2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1671049512&span=3780 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221214_131327_094 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/12/14/eovsa.lev1_mbd_12s.flare_id_20221214205500.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/12/14/20221214205500/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-12-14 2022-12-14] || 22:06 || M4.5 || [[File:EOVSA_20221214_M3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221214_M3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1671053040&span=5660 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221214_215700 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/12/14/eovsa.lev1_mbd_12s.flare_id_20221214220600.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/12/14/20221214220600/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-12-16 2022-12-16] || 19:06 || C9.1 || [[File:EOVSA_20221216_C9flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221216_C9flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1671216704&span=3448 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221216_112817_303 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/12/16/eovsa.lev1_mbd_12s.flare_id_20221216190600.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/12/16/20221216190600/ FITS Files] || VLA C-band data were obtained for this flare
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-12-17 2022-12-17] || 19:46 || M1.0 || [[File:EOVSA_20221217_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221217_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1671304696&span=4012 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221217_194000 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/12/17/eovsa.lev1_mbd_12s.flare_id_20221217194600.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/12/17/20221217194600/ FITS Files] || Nice east-limb filament eruption
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-12-21 2022-12-21] || 20:45 || C4.8 || [[File:EOVSA_20221221_C5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221221_C5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1671653044&span=5072 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221221_164321_564 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/12/21/eovsa.lev1_mbd_12s.flare_id_20221221204500.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/12/21/20221221204500/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-12-21 2022-12-21] || 22:12 || C6.9 || [[File:EOVSA_20221221_C6flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221221_C6flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1671659704&span=4704 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221221_164324_845 AIA?] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/12/21/eovsa.lev1_mbd_12s.flare_id_20221221221200.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/12/21/20221221221200/ FITS Files] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-12-22 2022-12-22] || 22:27 || B7.8 || [[File:EOVSA_20221222_burst.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221222_burst.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1671747308&span=1368 Yes] || AIA? ||[http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/12/22/eovsa.lev1_mbd_12s.flare_id_20221222222700.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/12/22/20221222222700/ FITS Files] || Intense decimetric emission with weak GS
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-12-25 2022-12-25] || 21:56 || C2.2 || [[File:EOVSA_20221225_C2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221225_C2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1672004472&span=2280 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221225_141233_601 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/12/25/eovsa.lev1_mbd_12s.flare_id_20221225215600.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/12/25/20221225215600/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-12-26 2022-12-26] || 16:57 || C4.4 || [[File:EOVSA_20221226_C4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221226_C4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1672072620&span=3556 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221226_165100 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/12/26/eovsa.lev1_mbd_12s.flare_id_20221226165700.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/12/26/20221226165700/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-12-26 2022-12-26] || 19:40 || C6.0 || [[File:EOVSA_20221226_C6flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221226_C6flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1672081200&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221226_120732_323 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/12/26/eovsa.lev1_mbd_12s.flare_id_20221226194000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/12/26/20221226194000/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-12-27 2022-12-27] || 16:24 || M1.2 || [[File:EOVSA_20221227_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221227_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1672157396&span=2476 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221227_161500 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/12/27/eovsa.lev1_mbd_12s.flare_id_20221227162400.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/12/27/20221227162400/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-12-27 2022-12-27] || 20:36 || C4.5 || [[File:EOVSA_20221227_C4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221227_C4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1672169080&span=7052 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221227_125318_392 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/12/27/eovsa.lev1_mbd_12s.flare_id_20221227203600.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/12/27/20221227203600/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-12-29 2022-12-29] || 18:18 || M2.4 || [[File:EOVSA_20221229_M2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221229_M2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1672165368&span=1520 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221229_120731_987 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/12/29/eovsa.lev1_mbd_12s.flare_id_20221229181800.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/12/29/20221229181800/ FITS Files] || A nice, long-duration limb flare
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-12-29 2022-12-29] || 18:18 || M2.4 || [[File:EOVSA_20221229_M2flare_ld.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221229_M2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1672336800&span=5995 Yes] ||[https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221229_120731_987 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/12/29/eovsa.lev1_mbd_12s.flare_id_20221229181800.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/12/29/20221229181800/ FITS Files] || Same flare as above, showing long decay
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-12-30 2022-12-30] || 19:09 || C4.0 || [[File:EOVSA_20221230_C4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221230_M3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1672426608&span=1860 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221230_120148_110 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/12/30/eovsa.lev1_mbd_12s.flare_id_20221230190900.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/12/30/20221230190900/ FITS Files] || This and the next flare could be considered one event
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-12-30 2022-12-30] || 19:35 || M3.7 || [[File:EOVSA_20221230_M3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221230_M3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1672427556&span=5224 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221230_120151_969 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/12/30/eovsa.lev1_mbd_12s.flare_id_20221230193500.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/12/30/20221230193500/ FITS Files] || Really nice on-disk event (flux rope)
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2022-12-31 2022-12-31] || 21:42 || C9.1 || [[File:EOVSA_20221231_C9flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2022/EOVSA_20221231_C9flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1672520840&span=4816 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20221231_141143_042 AIA] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2022/12/31/eovsa.lev1_mbd_12s.flare_id_20221231214200.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2022/12/31/20221231214200/ FITS Files]
|}

===January 2023===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || Comment
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-01-01 2023-01-01] || 19:33 || C1.1 || [[File:EOVSA_20230101_Cflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230101_Cflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1672601464&span=6792 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230101_193100 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-01-06 2023-01-06] || 18:47 || C6.1 || [[File:EOVSA_20230106_C6flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230106_C6flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1673027788&span=5124 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230106_184300 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-01-09 2023-01-09] || 18:46 || X2.0 || [[File:EOVSA_20230109_Xflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230109_Xflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1673288656&span=5000 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230109_183700 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-01-10 2023-01-10] || 17:48 || M1.3 || [[File:EOVSA_20230110_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230110_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1673372200&span=1848 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230110_174400 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-01-10 2023-01-10] || 22:47 || X1.0 || [[File:EOVSA_20230110_Xflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230110_Xflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1673389804&span=3860 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230110_223900 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-01-14 2023-01-14] || 20:12 || M3.5 || [[File:EOVSA_20230114_M3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230114_M3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1673726384&span=7012 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230114_123831_902 AIA]
|}

===February 2023===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || Comment
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-02-08 2023-02-08] || 21:10 || M1.7 || [[File:EOVSA_20230208_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230208_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1675889653&span=1908 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230208_133319_586 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-02-09 2023-02-09] || 18:25 || M1.8 || [[File:EOVSA_20230209_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230209_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1675966099&span=4036 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230209_181800 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-02-10 2023-02-10] || 22:38 || M1.3 || [[File:EOVSA_20230210_Mflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230210_Mflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1676067815&span=3580 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230210_223400 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-02-11 2023-02-11] || 15:50 || X1.2 || [[File:EOVSA_20230211_Xflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230211_Xflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1676129407&span=3812 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230211_154000 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-02-17 2023-02-17] || 20:03 || X2.3 || [[File:EOVSA_20230217_X2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230217_X2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1676662200&span=5996 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230217_193800 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-02-19 2023-02-19] || 19:28 || C4.0 || [[File:EOVSA_20230219_Cflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230219_Cflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1676834096&span=1740 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230219_151411_655 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-02-21 2023-02-21] || 20:12 || M5.1 || [[File:EOVSA_20230221_M5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230221_M5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1677009258&span=3068 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230221_122805_901 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-02-23 2023-02-23] || 18:20 || C8.9 || [[File:EOVSA_20230223_C8flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230223_C8flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1677175202&span=5996 No?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230223_103349_845 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-02-23 2023-02-23] || 23:12 || C6.2 || [[File:EOVSA_20230223_C6flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230223_C6flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1677193078&span=2576 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230223_153339_813 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-02-24 2023-02-24] || 20:20 || M3.7 || [[File:EOVSA_20230224_Mflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230224_Mflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1677268970&span=3228 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230224_124330_293 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-02-25 2023-02-25] || 19:30 || M5.9 || [[File:EOVSA_20230225_Mflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230225_Mflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1677353010&span=1328 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230225_184000 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-02-26 2023-02-26] || 19:17 || C2.8 || [[File:EOVSA_20230226_Cflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230226_Cflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1677438122&span=2504 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230226_191000 AIA]
|}

===March 2023===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || Comment
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-03-05 2023-03-05] || 21:35 || M5 || [[File:EOVSA_20230305_Mflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230305_Mflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1678051006&span=7720 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230305_135247_730 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-03-08 2023-03-08] || 22:42 || M1.4 || [[File:EOVSA_20230308_Mflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230308_Mflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1678314408&span=1972 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230308_150315_782 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-03-18 2023-03-18] || 20:51 || B8.6 || [[File:EOVSA_20230318_LWAflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230318_LWAflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1679171800&span=1676 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_FlareDetective-TriggerModule_20230319_073246_2023-03-18T20:37:58.350_1 AIA?] || OVRO-LWA data for this event
|}

===April 2023===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || Comment
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-04-07 2023-04-07] || 20:37 || C2.6 || [[File:EOVSA_20230407_C2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230407_C2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1680897600&span=3599 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230407_141603_800 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-04-07 2023-04-07] || 23:34 || C5.8 || [[File:EOVSA_20230407_C5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230407_C5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1680908403&span=5996 No?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230407_232400 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-04-11 2023-04-11] || 22:38 || C5.9 || [[File:EOVSA_20230411_Cflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230411_Cflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1681251480&span=4984 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230411_155354_226 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-04-14 2023-04-14] || 23:26 || M1.5 || [[File:EOVSA_20230414_Mflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_2023041M_Mflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1681513200&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230414_164207_271 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-04-18 2023-04-18] || 19:12 || C1.9 || [[File:EOVSA_20230418_Cflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230418_Cflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1681843892&span=3768 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230418_130744_198 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-04-21 2023-04-21] || 17:57 || M1.8 || [[File:EOVSA_20230421_Mflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230421_Mflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1682098468&span=2592 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230421_174400 AIA] || Halo CME associated
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-04-26 2023-04-27] || 01:00 || C3.0 || [[File:EOVSA_20230427_Cflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230427_Cflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1682556108&span=3000 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230426_181154_417 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-04-29 2023-04-29] || 23:02 || C3.2 || [[File:EOVSA_20230429_Cflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230429_Cflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1682808637&span=4240 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230429_224136_313 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-04-30 2023-04-30] || 20:35 || M2.1 || [[File:EOVSA_20230430_Mflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230430_Mflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1680908403&span=5996 No?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230430_155053_399 AIA]
|}

===May 2023===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || Comment
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-01 2023-05-01] || 21:46 || C3.4 || [[File:EOVSA_20230501_Cflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230501_Cflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1682974800&span=5996 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230501_150245_290 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-03 2023-05-03] || 20:53 || C4.1 || [[File:EOVSA_20230503_Cflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230503_Cflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1683145800&span=5996 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230503_140539_620 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-05 2023-05-05] || 15:45 || C8.2 || [[File:EOVSA_20230505_C8flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230505_C8flare.dat plot data] || No data || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230505_153900 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-06 2023-05-06] || 14:58 || C3.6 || [[File:EOVSA_20230506_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230506_C3flare.dat plot data] || No data || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230506_145000 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-06 2023-05-06] || 17:43 || C1.8 || [[File:EOVSA_20230506_C1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230506_C1flare.dat plot data] || No data || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230506_173800 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-06 2023-05-06] || 21:53 || C4.7 || [[File:EOVSA_20230506_C4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230506_C4flare.dat plot data] || No data || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230506_151803_530 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-07 2023-05-07] || 22:00 || M1.5 || [[File:EOVSA_20230507_Mflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230507_Mflare.dat plot data] || No data || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230507_154801_802 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-08 2023-05-08] || 14:19 || C9.5 || [[File:EOVSA_20230508_C9flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230508_C9flare.dat plot data] || No data || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230508_073558_677 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-08 2023-05-08] || 16:08 || C3.0 || [[File:EOVSA_20230508_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230508_C3flare.dat plot data] || No data || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230508_092343_854 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-08 2023-05-08] || 20:00 || M2.3 || [[File:EOVSA_20230508_M2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230508_M2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1683574200&span=5996 Yes?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230508_133846_921 AIA] || This flare occurred during the decay phase of the previous one
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-08 2023-05-08] || 21:20 || C3.4 || [[File:EOVSA_20230508_C34flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230508_C34flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1683579000&span=3596 Yes?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_FlareDetective-TriggerModule_20230509_054446_2023-05-08T21:18:46.349_1 AIA?]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-09 2023-05-09] || 14:01 || C5.5 || [[File:EOVSA_20230509_C5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230509_C5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1683639603&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230509_071747_481 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-09 2023-05-09] || 14:31 || C7.3 || [[File:EOVSA_20230509_C7flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230509_C7flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1683640803&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SWPC_20230509_204920_20230509142300 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-09 2023-05-09] || 18:40 || M4.2 || [[File:EOVSA_20230509_M4flare_log.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230509_M4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1683655203&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230509_121136_499 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-09 2023-05-09] || 20:47 || M5.0 || [[File:EOVSA_20230509_M5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230509_M5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1683664203&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230509_140844_197 AIA] || This flare occurred during the decay phase of the previous one
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-10 2023-05-10] || 14:18 || M2.1 || [[File:EOVSA_20230510_M2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230510_M2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1683727203&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230510_073601_718 AIA] || radio QPPs
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-10 2023-05-11] || 01:06 || C4.2 || [[File:EOVSA_20230511_C4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230511_C4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1683765003&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230510_183718_213 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-11 2023-05-11] || 18:26 || M1.2 || [[File:EOVSA_20230511_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230511_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1683828003&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230511_114153_846 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-12 2023-05-12] || 23:57 || C5.5 || [[File:EOVSA_20230512_C5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230512_C5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1683934203&span=3595 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230512_170553_590 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-13 2023-05-13] || 19:40 || C1.7 || [[File:EOVSA_20230513_C1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230513_C1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1684004403&span=3596 No?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_FlareDetective-TriggerModule_20230515_041635_2023-05-13T19:39:56.072_1 AIA?]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-18 2023-05-18] || 20:20 || M3.9 || [[File:EOVSA_20230518_M3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230518_M3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1684440003&span=3596 No?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230518_133724_506 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-18 2023-05-19] || 00:48 || M5.4 || [[File:EOVSA_20230519_M5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230519_M5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1684454403&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230518_180721_389 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-19 2023-05-19] || 16:17 || C3.3 || [[File:EOVSA_20230519_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230519_C3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1684512003&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230519_095224_075 AIA?]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-19 2023-05-19] || 19:10 || C5.2 || [[File:EOVSA_20230519_C5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230519_C5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1684522803&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230519_123127_346 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-20 2023-05-20] || 14:58 || M5.6 || [[File:EOVSA_20230520_M56flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230520_M56flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1684593603&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230520_081620_432 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-20 2023-05-20] || 23:03 || M5.2 || [[File:EOVSA_20230520_M52flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230520_M52flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1684622403&span=3596 Yes?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230520_225200 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-21 2023-05-21] || 15:57 || M2.6 || [[File:EOVSA_20230521_M2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230521_M2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1684683603&span=3596 Yes?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230521_092233_024 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-21 2023-05-21] || 21:06 || C6.1 || [[File:EOVSA_20230521_C4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230521_C4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1684701603&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230521_141616_911 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-23 2023-05-23] || 14:36 || C6.8 || [[File:EOVSA_20230523_C2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230523_C2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1684850403&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230523_143400 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-24 2023-05-24] || 17:15 || M1.9 || [[File:EOVSA_20230524_Mflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230524_Mflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1684947603&span=3596 No?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230524_103532_315 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-24 2023-05-24] || 19:03 || C5.1 || [[File:EOVSA_20230524_C5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230524_C5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1684953603&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230524_122336_829 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-24 2023-05-24] || 19:48 || C3.6 || [[File:EOVSA_20230524_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230524_C3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1684956603&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230524_130526_210 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-25 2023-05-25] || 14:42 || M1.1 || [[File:EOVSA_20230525_Mflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230525_Mflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1685024403&span=3596 No?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230525_075934_688 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-26 2023-05-26] || 22:37 || C7.0 || [[File:EOVSA_20230526_Mflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230526_Mflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1685139603&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230526_155637_451 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-27 2023-05-27] || 16:35 || C1.5 || [[File:EOVSA_20230527_Cflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230527_Cflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1685204403&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_FlareDetective-TriggerModule_20230527_164956_2023-05-27T16:34:20.072_1 AIA?]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-27 2023-05-27] || 22:36 || C1.5 || [[File:EOVSA_20230527_C1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230527_C1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1685225403&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230527_204804_852 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-29 2023-05-29] || 18:19 || C6.5 || [[File:EOVSA_20230529_C6flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230529_C6flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1685383203&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230529_113255_226 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-05-31 2023-05-31] || 16:37 || C3.3 || [[File:EOVSA_20230531_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230531_C3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1685548803&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230531_132341_379 AIA]
|-
|}

===June 2023===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || Comments
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-01 2023-06-01] || 20:33 || C6.3 || [[File:EOVSA_20230601_C6flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230601_C6flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1685649603&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230601_135356_470 SSW Movie]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-02 2023-06-02] || 21:08 || C1.2 || [[File:EOVSA_20230602_C1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230602_C1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1685739003&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_FlareDetective-TriggerModule_20230603_062755_2023-06-02T21:07:32.073_1 AIA?]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-03 2023-06-03] || 21:46 || C2.8 || [[File:EOVSA_20230603_C2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230603_C2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1685826003&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230603_150013_348 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-05 2023-06-05] || 22:55 || C1.7 || [[File:EOVSA_20230605_C1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230605_C1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1686004203&span=3596 No?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_FlareDetective-TriggerModule_20230606_063210_2023-06-05T22:54:56.072_1 AIA?]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-06 2023-06-06] || 18:58 || C7.5 || [[File:EOVSA_20230606_C7flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230606_C7flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1686076200&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230606_170224_461 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-07 2023-06-07] || 18:28 || C9.2 || [[File:EOVSA_20230607_C9flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230607_C9flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1686160800&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230607_182500 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-09 2023-06-09] || 14:37 || C4.4 || [[File:EOVSA_20230609_C4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230609_C4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1686319200&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230609_142800 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-09 2023-06-09] || 17:04 || M2.5 || [[File:EOVSA_20230609_M2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230609_M2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1686330000&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230609_102408_386 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-12 2023-06-12] || 20:22 || C3.3 || [[File:EOVSA_20230612_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230612_C3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1686600000&span=3596 No?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230612_201900 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-13 2023-06-13] || 20:30 || C3.9 || [[File:EOVSA_20230613_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230613_C3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1686687000&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230613_141409_857 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-17 2023-06-18] || 00:30 || M1.3 || [[File:EOVSA_20230618_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230618_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1687046400&span=3595 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230617_174545_729 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-20 2023-06-20] || 17:07 || X1.1 || [[File:EOVSA_20230620_X1flare_log.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230620_X1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1687278603&span=3596 No?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230620_102502_288 AIA] || Limb CME associated
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-20 2023-06-20] || 17:55 || M1.2 || [[File:EOVSA_20230620_Mflare_log.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230620_Mflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1687282203&span=3596 No] || AIA? || Low frequency emission during the decay phase of the previous flare
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-21 2023-06-21] || 15:37 || M1.0 || [[File:EOVSA_20230621_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230621_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1687361403&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230621_085124_237 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-21 2023-06-22] || 01:06 || C6.2|| [[File:EOVSA_20230622_C6flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230622_C6flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1687393803&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230621_182509_679 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-22 2023-06-22] || 23:37 || M4.9|| [[File:EOVSA_20230622_M4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230622_M4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1687474803&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230622_232900 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-24 2023-06-24] || 21:13 || C4.9|| [[File:EOVSA_20230624_C4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230624_C4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1687640403&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230624_142753_127 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-25 2023-06-25] || 21:58 || C6.8|| [[File:EOVSA_20230625_C6flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230625_C6flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1687728603&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230625_151557_668 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-25 2023-06-25] || 22:59 || C1.6|| [[File:EOVSA_20230625_C1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230625_C1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1687732203&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230625_161624_241 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-25 2023-06-26] || 01:34 || C2.2|| [[File:EOVSA_20230626_C2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230626_C2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1687741202&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230625_184907_475 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-26 2023-06-26] || 16:18 || M1.6|| [[File:EOVSA_20230626_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230626_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1687795202&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230626_093719_112 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-26 2023-06-26] || 22:19 || C2.3|| [[File:EOVSA_20230626_C23flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230626_C23flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1687816802&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230626_153412_571 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-27 2023-06-27] || 15:12 || C9.8|| [[File:EOVSA_20230627_C9flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230627_C9flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1687878002&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230627_083118_255 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-27 2023-06-27] || 22:26 || C4.4|| [[File:EOVSA_20230627_C4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230627_C4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1687903202&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230627_154930_371 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-29 2023-06-29] || 14:10 || M3.8|| [[File:EOVSA_20230629_M3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230629_M3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1688047202&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230629_140000 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-29 2023-06-29] || 16:36 || C2.5|| [[File:EOVSA_20230629_C2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230629_C2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1688054402&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230629_105825_422 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-29 2023-06-29] || 22:00 || C5.3|| [[File:EOVSA_20230629_C5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230629_C5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1688074202&span=3595 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230629_151926_316 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-06-30 2023-06-30] || 18:56 || C3.7|| [[File:EOVSA_20230630_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230630_C3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1688149802&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230630_122202_879 AIA]
|-
|}

===July 2023===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || Comments
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-07-04 2023-07-04] || 19:18 || C8.0 || [[File:EOVSA_20230704_C8flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230704_C8flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1688497200&span=3599 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230704_125135_617 SSW Movie]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-07-11 2023-07-11] || 14:27 || M2.0 || [[File:EOVSA_20230711_M2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230711_M2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1689084000&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230711_075733_525 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-07-11 2023-07-11] || 18:00 || M6.8 || [[File:EOVSA_20230711_M6flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230711_M6flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1689096600&span=3595 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230711_175100 AIA] || nice limb eruption; radio oscillations
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-07-11 2023-07-11] || 22:12 || M5.8 || [[File:EOVSA_20230711_M5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230711_M5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1689112800&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230711_220400 AIA] || from same active region as above two
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-07-16 2023-07-16] || 17:40 || M4.0 || [[File:EOVSA_20230716_M4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230716_M4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1689528000&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230716_110343_486 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-07-17 2023-07-17] || 22:45 || M2.7 || [[File:EOVSA_20230717_M2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230717_M2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1689633160&span=2632 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230717_161526_577 AIA] || random twisted?
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-07-17 2023-07-17] || 23:36 || M5.7 || [[File:EOVSA_20230717_M5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230717_M5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1689635312&span=6468 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230717_170023_084 AIA]
|| Missed the beginning, and data dropouts every 1 min (reason unknown)
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-07-18 2023-07-18] || 19:25 || M1.3 || [[File:EOVSA_20230718_Mflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230718_Mflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1689706800&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230718_124235_780 AIA?]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-07-19 2023-07-19] || 17:15 || M3.8 || [[File:EOVSA_20230719_C5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230719_M3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1689785715&span=5932 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230719_104539_465 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-07-20 2023-07-20] || 19:53 || C9.7 || [[File:EOVSA_20230720_C9flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230720_C9flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1690140600&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230720_194000 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-07-23 2023-07-23] || 14:55 || C5.2 || [[File:EOVSA_20230723_C5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230723_C5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1690122600&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230723_081328_262 AIA] || Very strong event as observed by OVRO-LWA
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-07-25 2023-07-25] || 23:43 || C3.6 || [[File:EOVSA_20230725_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230725_C3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1690324200&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230725_171225_081 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-07-26 2023-07-26] || 15:57 || M2.1 || [[File:EOVSA_20230726_M2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230726_M2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1690385400&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230726_091545_924 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-07-28 2023-07-28] || 14:50 || C7.8 || [[File:EOVSA_20230728_C7flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230728_C7flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1690554600&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230728_080936_528 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-07-28 2023-07-28] || 20:51 || C6.0 || [[File:EOVSA_20230728_C5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230728_C5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1690576200&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230728_144836_412 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-07-29 2023-07-29] || 16:20 || M1.4 || [[File:EOVSA_20230729_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230729_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1690646400&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230729_094257_966 AIA] || radio oscillations and fine structures
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-07-30 2023-07-30] || 22:19 || C1.5 || [[File:EOVSA_20230730_C1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230730_C1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1690754400&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230730_154003_446 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-07-31 2023-07-31] || 22:46 || C5.4 || [[File:EOVSA_20230731_C5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230731_C5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1690842601&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230731_160654_141 AIA]
|-
|}

===August 2023===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || Comments
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-08-01 2023-08-02] || 00:21 || C7.9 || [[File:EOVSA_20230802_C7flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230802_C7flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1690934401&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230801_174531_324 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-08-02 2023-08-02] || 14:51 || M1.7 || [[File:EOVSA_20230802_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230802_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1690986001&span=3595 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230802_144600 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-08-02 2023-08-02] || 16:20 || M1.3 || [[File:EOVSA_20230802_M13flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230802_M13flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1690992001&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230802_113548_453 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-08-02 2023-08-02] || 19:11 || M1.1 || [[File:EOVSA_20230802_M11flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230802_M11flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1691002201&span=2396 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230802_132022_907 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-08-05 2023-08-05] || 22:05 || X1.6 || [[File:EOVSA_20230805_X1flare_log.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230805_X1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1691271602&span=5996 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230805_153621_474 AIA] || long-duration limb flare
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-08-06 2023-08-06] || 18:35 || M5.5 || [[File:EOVSA_20230806_M5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230806_M5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1691345402&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230806_115350_076 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-08-07 2023-08-07] || 20:58 || X1.5 || [[File:EOVSA_20230807_X1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230807_X1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1691438400&span=7196 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230807_135951_604 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-08-14 2023-08-14] || 20:42 || C2.6 || [[File:EOVSA_20230814_C2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230814_C2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1692043803&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230814_142349_832 AIA?]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-08-15 2023-08-15] || 21:56 || C2.3 || [[File:EOVSA_20230815_C2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230815_C2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1692135000&span=3595 No?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230815_150536_929 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-08-18 2023-08-18] || 19:20 || C3.7 || [[File:EOVSA_20230818_C3flare_zoom.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230818_C3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1692385803&span=1796 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230818_190900 AIA] || OVRO-LWA event associated
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-08-18 2023-08-18] || 21:20 || C3.0 || [[File:EOVSA_20230818_C30flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230818_C30flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1692393003&span=1796 No?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230818_144807_205 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-08-24 2023-08-24] || 15:52 || C1.1 || [[File:EOVSA_20230824_C1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230824_C1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1692891600&span=1196 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230824_090901_282 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-08-24 2023-08-25] || 01:04 || M1.5 || [[File:EOVSA_20230825_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230825_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1692925200&span=1196 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230824_182431_341 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-08-26 2023-08-26] || 21:48 || C2.6 || [[File:EOVSA_20230826_C2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230826_C2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1693085400&span=2996 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230827_232350_172 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-08-30 2023-08-30] || 17:15 || C1.0 || [[File:EOVSA_20230830_Cflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230830_Cflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1693414801&span=3596 No?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_FlareDetective-TriggerModule_20230830_194143_2023-08-30T17:14:32.072_1 AIA?]
|-
|}

===September 2023===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || Comments
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-09-02 2023-09-03] || 00:18 || M1.1 || [[File:EOVSA_20230903_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230903_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1693699201&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230902_173641_040 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-09-07 2023-09-07] || 19:01 || M2.1 || [[File:EOVSA_20230907_M2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230907_M2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1694111400&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230907_122403_304 AIA] || OVRO-LWA event associated
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-09-11 2023-09-11] || 21:11 || C8.2 || [[File:EOVSA_20230911_C8flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230911_C8flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1694466000&span=3595 Yes?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230911_210700 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-09-12 2023-09-12] || 21:54 || C5.6 || [[File:EOVSA_20230912_C5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230912_C5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1694554200&span=3595 No?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230912_215000 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-09-14 2023-09-14] || 19:30 || M1.9 || [[File:EOVSA_20230914_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230914_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1694718000&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230914_124529_118 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-09-14 2023-09-14] || 21:25 || M2.5 || [[File:EOVSA_20230914_M2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230914_M2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1694725200&span=3596 Yes?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230914_211700 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-09-16 2023-09-16] || 15:56 || C3.7 || [[File:EOVSA_20230916_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230916_C3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1694878200&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230916_122734_398 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-09-17 2023-09-17] || 16:02 || C3.5 || [[File:EOVSA_20230917_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230917_C3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1694964600&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230917_091819_706 AIA] || OVRO-LWA event associated flare and nearby jet connection
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-09-18 2023-09-18] || 20:28 || C3.9 || [[File:EOVSA_20230918_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230918_C3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1695067200&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230918_152105_564 AIA] || OVRO-LWA event associated
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-09-19 2023-09-19] || 20:09 || M4.0 || [[File:EOVSA_20230919_M4flare_log.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230919_M4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1695152400&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230919_132700_493 AIA] || OVRO-LWA event associated
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-09-19 2023-09-19] || 22:30 || C9.7 || [[File:EOVSA_20230919_C9flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230919_C9flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1695160800&span=3596 No?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230919_222100 AIA] || OVRO-LWA event associated
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-09-20 2023-09-20] || 18:39 || C5.5 || [[File:EOVSA_20230920_C5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230920_C5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1695232800&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230920_183600 AIA] || jets in two directions?
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-09-21 2023-09-21] || 19:53 || B3.7 || [[File:EOVSA_20230921_Cflare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230921_Cflare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1695324600&span=3596 Yes] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-09-22 2023-09-22] || 17:09 || M1.5 || [[File:EOVSA_20230922_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230922_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1695400800&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230922_093700_597 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-09-22 2023-09-22] || 19:28 || C9.8 || [[File:EOVSA_20230922_C9flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230922_C9flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1695409200&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230922_192000 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-09-24 2023-09-24] || 14:57 || M1.0 || [[File:EOVSA_20230924_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230924_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1695565800&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230924_081204_660 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-09-25 2023-09-25] || 18:58 || C4.2 || [[File:EOVSA_20230925_C4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230925_C4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1695666601&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230925_121450_126 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-09-26 2023-09-26] || 16:17 || C4.3 || [[File:EOVSA_20230926_C4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230926_C4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1695744001&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230926_094146_437 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-09-30 2023-09-30] || 16:05 || C6.3 || [[File:EOVSA_20230930_C6flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20230930_C6flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1696087801&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20230930_092713_343 AIA]
|-
|}

===October 2023===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || Comments
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-10-07 2023-10-07] || 23:20 || C5.2 || [[File:EOVSA_20231007_C5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20231007_C5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1696719600&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20231007_163926_747 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-10-09 2023-10-09] || 19:00 || C9.1 || [[File:EOVSA_20231009_C9flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20231009_C9flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1696876200&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20231009_122416_257 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-10-15 2023-10-15] || 16:32 || C3.9 || [[File:EOVSA_20231015_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20231015_C3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1697385600&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20231015_162200 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-10-16 2023-10-16] || 16:04 || C9.7 || [[File:EOVSA_20231016_C9flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20231016_C9flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1697470200&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20231016_155900 AIA]
|-
|}

===November 2023===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || Comments
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-11-02 2023-11-02] || 19:16 || M1.0 || [[File:EOVSA_20231102_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20231102_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1698950024&span=4848 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20231102_133259_445 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-11-05 2023-11-05] || 17:40 || C4.5 || [[File:EOVSA_20231105_C4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20231105_C4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1699204895&span=2832 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20231105_095347_705 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-11-11 2023-11-11] || 16:45 || C1.8 || [[File:EOVSA_20231111_C1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20231111_C1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1699719940&span=2096 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20231111_090519_561 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-11-11 2023-11-11] || 18:05 || C4.8 || [[File:EOVSA_20231111_C4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20231111_C4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1699724920&span=1840 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20231111_160236_171 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-11-14 2023-11-14] || 23:04 || M1.1 || [[File:EOVSA_20231114_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20231114_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1700002152&span=5304 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20231114_160322_585 AIA]
|-
|}

===December 2023===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || Comments
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-12-01 2023-12-01] || 19:22 || C3.3 || [[File:EOVSA_20231201_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20231201_C3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1701457202&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20231201_1917 AIA?]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-12-01 2023-12-01] || 21:15 || M1.0 || [[File:EOVSA_20231201_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20231201_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1701464402&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20231201_2055 AIA?]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-12-01 2023-12-01] || 21:52 || C5.0 || [[File:EOVSA_20231201_C5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20231201_C5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1701465602&span=3595 Yes] || [AIA?]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-12-06 2023-12-06] || 18:54 || C4.8 || [[File:EOVSA_20231206_C4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20231206_C4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1701888001&span=3595 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20231206_184700 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-12-07 2023-12-07] || 18:12 || C4.1 || [[File:EOVSA_20231207_C4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20231207_C4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1701971401&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20231207_1802 AIA?]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-12-07 2023-12-07] || 20:53 || C8.2 || [[File:EOVSA_20231207_C8flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20231207_C8flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1701980401&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20231207_2046 AIA?]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-12-08 2023-12-08] || 23:02 || M5.5 || [[File:EOVSA_20231208_M5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20231208_M5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1702075801&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20231208_2257 AIA?]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-12-10 2023-12-10] || 22:43 || M1.4 || [[File:EOVSA_20231210_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20231210_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1702246202&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20231210_2237 AIA?]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-12-14 2023-12-14] || 17:00 || X2.7 || [[File:EOVSA_20231214_X2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20231214_X2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1702571402&span=10796 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20231214_164700 AIA] || Flare decay phase: [[File:EOVSA_20231214_X2decay2_log.png|thumb|center|100px|]] [[File:EOVSA_20231214_X2decay_log.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20231214_X2decay.dat plot data]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-12-15 2023-12-15] || 21:20 || C5.5 || [[File:EOVSA_20231215_C5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20231215_C5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1702674002&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20231215_2112 AIA?]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-12-20 2023-12-20] || 18:42 || C7.3 || [[File:EOVSA_20231220_C7flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20231220_C7flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1703096402&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20231220_1839 AIA?]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-12-21 2023-12-21] || 21:20 || C4.0 || [[File:EOVSA_20231221_C4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20231221_C4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1703192402&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20231221_211400 AIA]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-12-24 2023-12-24] || 16:43 || M2.7 || [[File:EOVSA_20231224_M2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20231224_M2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1703434803&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20231224_1637 AIA?]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-12-31 2023-12-31] || 19:01 || M1.0 || [[File:EOVSA_20231231_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20231231_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1704047403&span=21595 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20231231_1844 AIA?]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-12-31 2023-12-31] || 20:30 || C6.6 || [[File:EOVSA_20231231_C6flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20231231_C6flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1704047403&span=21595 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20231231_2028 AIA?]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2023-12-31 2023-12-31] || 21:40 || X5.0 || [[File:EOVSA_20231231_X5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2023/EOVSA_20231231_X5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1704047403&span=21595 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20231231_2136 AIA?]
|-
|}

===January 2024===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || EOVSA Images || Comments
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-01-02 2024-01-02] || 18:10 || M1.2 || [[File:EOVSA_20240102_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240102_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1704218403&span=5396 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240102_1802 AIA?] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2024/01/02/eovsa.lev1_mbd_12s.flare_id_20240102181000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2024/01/02/20240102181000/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-01-02 2024-01-02] || 22:01 || C1.1 || [[File:EOVSA_20240102_C1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240102_C1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1704231603&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240102_2156 AIA?] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2024/01/02/eovsa.lev1_mbd_12s.flare_id_20240102220100.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2024/01/02/20240102220100/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-01-03 2024-01-03] || 17:50 || B8.9 || [[File:EOVSA_20240103_B8flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240103_B8flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1704303003&span=3596 Yes] || [AIA?] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2024/01/03/eovsa.lev1_mbd_12s.flare_id_20240103175000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2024/01/03/20240103175000/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-01-03 2024-01-03] || 19:45 || C2.1 || [[File:EOVSA_20240103_C2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240103_C2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1704309603&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240103_1938 AIA?] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2024/01/03/eovsa.lev1_mbd_12s.flare_id_20240103194500.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2024/01/03/20240103194500/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-01-06 2024-01-06] || 16:30 || C2.4 || [[File:EOVSA_20240106_C2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240106_C2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1704556803&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240106_1626 AIA?] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2024/01/06/eovsa.lev1_mbd_12s.flare_id_20240106163000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2024/01/06/20240106163000/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-01-06 2024-01-06] || 21:57 || C1.8 || [[File:EOVSA_20240106_C1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240106_C1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1704576603&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_20240106_215300 AIA?] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2024/01/06/eovsa.lev1_mbd_12s.flare_id_20240106215700.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2024/01/06/20240106215700/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-01-10 2024-01-10] || 18:20 || C2.8 || [[File:EOVSA_20240110_C2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240110_C2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1704909603&span=3596 Yes] || [AIA?] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2024/01/10/eovsa.lev1_mbd_12s.flare_id_20240110182000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2024/01/10/20240110182000/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-01-10 2024-01-10] || 19:00 || C6.5 || [[File:EOVSA_20240110_C6flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240110_C6flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1704911403&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240110_1856 AIA?] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2024/01/10/eovsa.lev1_mbd_12s.flare_id_20240110190000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2024/01/10/20240110190000/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-01-11 2024-01-11] || 17:51 || M1.5 || [[File:EOVSA_20240111_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240111_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1704994803&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240111_1749 AIA?] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2024/01/11/eovsa.lev1_mbd_12s.flare_id_20240111175100.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2024/01/11/20240111175100/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-01-11 2024-01-11] || 20:12 || C7.9 || [[File:EOVSA_20240111_C7flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240111_C7flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1705002603&span=3596 Yes] || [AIA?] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2024/01/11/eovsa.lev1_mbd_12s.flare_id_20240111201200.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2024/01/11/20240111201200/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-01-21 2024-01-21] || 20:12 || C5.8 || [[File:EOVSA_20240121_C5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240121_C5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1705867200&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240121_2010 AIA?] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2024/01/21/eovsa.lev1_mbd_12s.flare_id_20240121201200.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2024/01/21/20240121201200/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-01-22 2024-01-22] || 19:18 || M1.0 || [[File:EOVSA_20240122_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240122_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1705950000&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240122_1913 AIA?] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2024/01/22/eovsa.lev1_mbd_12s.flare_id_20240122191800.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2024/01/22/20240122191800/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-01-22 2024-01-22] || 21:20 || M3.4 || [[File:EOVSA_20240122_M3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240122_M3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1705957800&span=7195 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240122_2114 AIA?] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2024/01/22/eovsa.lev1_mbd_12s.flare_id_20240122212000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2024/01/22/20240122212000/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-01-22 2024-01-22] || 21:40 || M1.6 || [[File:EOVSA_20240122_M16flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240122_M16flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1705957800&span=7195 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240122_2136 AIA?] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2024/01/22/eovsa.lev1_mbd_12s.flare_id_20240122214000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2024/01/22/20240122214000/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-01-23 2024-01-23] || 16:37 || M4.3 || [[File:EOVSA_20240123_M4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240123_M4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1706026200&span=7196 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240123_1636 AIA?] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2024/01/23/eovsa.lev1_mbd_12s.flare_id_20240123163700.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2024/01/23/20240123163700/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-01-23 2024-01-23] || 17:38 || C7.3 || [[File:EOVSA_20240123_C7flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240123_C7flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1706026200&span=7196 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240123_1732 AIA?] || [http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2024/01/23/eovsa.lev1_mbd_12s.flare_id_20240123173800.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2024/01/23/20240123173800/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-01-23 2024-01-23] || 21:03 || C4.9 || [[File:EOVSA_20240123_C4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240123_C4flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1706042400&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240123_2057 AIA?] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-01-24 2024-01-24] || 21:08 || M1.3 || [[File:EOVSA_20240124_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240124_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1706128800&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240124_2044 AIA?] ||[http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2024/01/24/eovsa.lev1_mbd_12s.flare_id_20240124210800.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2024/01/24/20240124210800/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-01-29 2024-01-29] || 16:38 || C5.9 || [[File:EOVSA_20240129_C5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240129_C5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1706544000&span=3596 No?] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240129_1629 AIA?] ||[http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2024/01/29/eovsa.lev1_mbd_12s.flare_id_20240129163800.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2024/01/29/20240129163800/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-01-29 2024-01-29] || 22:31 || C1.8 || [[File:EOVSA_20240129_C1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240129_C1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1706565600&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240129_2228 AIA?] ||[http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2024/01/29/eovsa.lev1_mbd_12s.flare_id_20240129223100.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2024/01/29/20240129223100/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-01-30 2024-01-30] || 17:37 || C5.7 || [[File:EOVSA_20240130_C5flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240130_C5flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1706634000&span=3596 No] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240130_1734 AIA?] ||[http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2024/01/30/eovsa.lev1_mbd_12s.flare_id_20240130173700.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2024/01/30/20240130173700/ FITS Files]
|-
|}

===February 2024===
{| class="wikitable"
! Date || Time (UT) || GOES Class || Spectrogram || STIX Coverage || AIA Movie || EOVSA Images || Comments
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-02-01 2024-02-01] || 22:33 || C1.2 || [[File:EOVSA_20240201_C1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240201_C1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1706824800&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240201_2231 AIA?] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-02-02 2024-02-02] || 16:30 || C3.2 || [[File:EOVSA_20240202_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240202_C3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1706890203&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240202_1622 AIA?] ||[http://ovsa.njit.edu/SynopticImg/eovsamedia/eovsa-browser/2024/02/02/eovsa.lev1_mbd_12s.flare_id_20240202163000.mp4 Quicklook Movie] [http://ovsa.njit.edu/fits/flares/2024/02/02/20240202163000/ FITS Files]
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-02-02 2024-02-02] || 16:47 || C2.6 || [[File:EOVSA_20240202_C2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240202_C2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1706890203&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240202_1646 AIA?] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-02-04 2024-02-04] || 20:55 || M1.3 || [[File:EOVSA_20240204_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240204_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1707078603&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240204_2052 AIA?] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-02-04 2024-02-04] || 22:27 || M2.7 || [[File:EOVSA_20240204_M2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240204_M2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1707084603&span=5396 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240204_2220 AIA?] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-02-05 2024-02-05] || 23:06 || C6.1 || [[File:EOVSA_20240205_C6flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240205_C6flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1707172803&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240205_2302 AIA?] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-02-06 2024-02-06] || 17:34 || C3.3 || [[File:EOVSA_20240206_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240206_C3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1707240003&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240206_1737 AIA?] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-02-06 2024-02-06] || 18:45 || M1.3 || [[File:EOVSA_20240206_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240206_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1707242403&span=5396 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240206_1838 AIA?] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-02-07 2024-02-07] || 17:52 || M1.4 || [[File:EOVSA_20240207_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240207_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1707327000&span=5396 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240207_1741 AIA?] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-02-07 2024-02-07] || 20:25 || C3.4 || [[File:EOVSA_20240207_C3flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240207_C3flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1707336000&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240207_2009 AIA?] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-02-08 2024-02-08] || 17:05 || C7.0 || [[File:EOVSA_20240208_C7flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240208_C7flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1707411000&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240208_1656 AIA?] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-02-08 2024-02-08] || 17:36 || C2.4 || [[File:EOVSA_20240208_C2flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240208_C2flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1707411000&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240208_1750 AIA?] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-02-08 2024-02-08] || 19:02 || M1.3 || [[File:EOVSA_20240208_M1flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240208_M1flare.dat plot data] || [https://datacenter.stix.i4ds.net/view/plot/lightcurves?start=1707417600&span=3596 Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240208_1856 AIA?] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-02-08 2024-02-08] || 23:32 || M4.0 || [[File:EOVSA_20240208_M4flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240208_M4flare.dat plot data] || [Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240208_2316 AIA?] ||
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-02-08 2024-02-09] || 00:09 || M4.0 || [[File:EOVSA_20240208_M4flare_decay.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240208_M4flare_decay.dat plot data] || [Yes] || [https://www.lmsal.com/hek/her?cmd=view-voevent&ivorn=ivo://helio-informatics.org/FL_SSWLatestEvents_gev_20240208_2316 AIA?] || || Low frequency emission during the decay phase of the previous flare
|-
| [http://ovsa.njit.edu/browser/?suntoday_date=2024-02-10 2024-02-10] || 23:04 || M9.0 || [[File:EOVSA_20240210_M9flare.png|thumb|center|100px|]] [http://ovsa.njit.edu/events/2024/EOVSA_20240210_M9flare.dat plot data] || [Yes] || ||
|-
|}

== Python code to read plotdata file ==
<pre>
from __future__ import print_function
def rd_datfile(file):
''' Read EOVSA binary spectrogram file and return a dictionary with times
in Julian Date, frequencies in GHz, and cross-power data in sfu.

Return Keys:
'time' Numpy array of nt times in JD format
'fghz' Numpy array of nf frequencies in GHz
'data' Numpy array of size [nf, nt] containing cross-power data

Returns empty dictionary ({}) if file size is not compatible with inferred dimensions
'''
import struct
import numpy as np
def dims(file):
# Determine time and frequency dimensions (assumes the file has fewer than 10000 times)
f = open(file,'rb')
tmp = f.read(83608) # max 10000 times and 451 frequencies
f.close()
nbytes = len(tmp)
tdat = np.array(struct.unpack(str(int(nbytes/8))+'d',tmp[:nbytes]))
nt = np.where(tdat < 2400000.)[0]
nf = np.where(np.logical_or(tdat[nt[0]:] > 18, tdat[nt[0]:] < 1))[0]
return nt[0], nf[0]
nt, nf = dims(file)
f = open(file,'rb')
tmp = f.read(nt*8)
times = struct.unpack(str(nt)+'d',tmp)
tmp = f.read(nf*8)
fghz = struct.unpack(str(nf)+'d',tmp)
tmp = f.read()
f.close()
if len(tmp) != nf*nt*4:
print('File size is incorrect for nt=',nt,'and nf=',nf)
return {}
data = np.array(struct.unpack(str(nt*nf)+'f',tmp)).reshape(nf,nt)
return {'time':times, 'fghz':fghz, 'data':data}
</pre>

== IDL code to read plotdata file ==
<pre>
function rd_datfile,file
; Read EOVSA binary spectrogram file and return a structure with times
; in Julian Date, frequencies in GHz, and cross-power data in sfu.
;
; Return tags:
; 'time' Array of nt times in JD format
; 'fghz' Array of nf frequencies in GHz
; 'data' Array of size [nf, nt] containing cross-power data
;
; Returns empty dictionary ({}) if file size is not compatible with inferred dimensions
openr,/get_lun,lun,file
tmp = dblarr(10451)
readu,lun,tmp
free_lun,lun
nt = (where(tmp lt 2400000.))[0]
nf = (where(tmp[nt[0]:*] gt 18 or tmp[nt[0]:*] lt 1))[0]
times = dblarr(nt)
fghz = dblarr(nf)
data = fltarr(nt, nf)
openr,/get_lun,lun,file
readu,lun,times
readu,lun,fghz
readu,lun,data
free_lun,lun
data = create_struct('time',times,'fghz',fghz,'data',transpose(data))
return, data
end
</pre>

Tohban OVRO-LWA Imaging Tutorial

2024-01-16T15:29:03Z

Dgary: /* What Happens When You Run the Script */

=Initial Setup=
The OVRO-LWA has three solar modes that can operate concurrently. These are (1) the beamformer, which creates a high-resolution spectrogram of the solar activity each day, (2) a slow visibility mode that records data in CASA ms format for all 352 antennas and all 3072 frequencies at 10-s cadence, and (3) a fast visibility mode that records data for a 48-antenna subset (generally the outer antennas) and 768 frequencies at 1-s cadence. The recorders that record the data are all activated separately, so it is not guaranteed that data from all three modes are available at any one time. Also, because of the vast data volume most of the recorded data are not saved, but rather are overwritten after a day or so, hence any data that are wanted must be explicitly saved by copying it to another location. Again because of the large volume of data, such copying is too slow to save much data (at least at present), so we can generally save only about an hour of data per day.

'''Note: This tutorial only describes how to work with the slow visibility data at the moment.'''

==Python Environment==
The imaging pipeline is written in Python 3, so in order to use it one must set up a Python 3 environment. These instructions assume you are working in your own home directory on the Pipeline machine at OVRO. First enter the bash shell if you are not already in it. Type <code>echo $0</code> to see what shell you are in. If that returns something other than -bash, type <code>bash</code> to enter the shell. Next check if you have the line <code>alias loadpyenv3.8='source /home/user/.setenv_pyenv38'</code> in your ~/.bash_aliases file. If not, add it using your favorite editor, then activate it with <code>source ~/.bash_aliases</code>. From there, you can type <code>loadpyenv3.8</code> to enter the Python 3.8 environment. Finally, from your home folder, type <code> git clone https://github.com/binchensun/ovro-lwa-solar </code> to install the OVRO-LWA code. To test your Python environment, log out and log in again fresh, then type
<pre>
$> loadpyenv3.8
$> ipython --pylab
import sys
sys.path.append('/home/dgary/ovro-lwa-solar') # Replace with your own home directory
from ovrolwasolar import solar_pipeline
</pre>
If that succeeds, you should be ready to proceed.

==Where to Find Data==
The next step is to find the data you want to work with. You will need some calibration data as well as the solar data for your target date. As of this writing, the existing solar data on Pipeline, is in two separate places: /nas5/ovro-lwa-data (data up to 2023-09-03) and /nas6/ovro-lwa-data (data from 2023-09-18 and later). All of the existing beamformed data (spectrograms) are in /nas5/ovro-lwa-data/beam/beam-data.

'''This tutorial uses the example of the type II burst on 2023-07-28.'''

==Examining the Spectrogram for Your Date==
It is good practice to examine the spectrogram for your date/time, to guide your selection of frequencies and times to use for imaging. You can check the folders and subfolders in /nas5/ovro-lwa-data/beam/beam-data to see what files exist. Note that the filenames have the Modified Julian Data (mjd) followed by hours, minutes, seconds in the format <mjdday>.<hh><mm><ss>?????????? where the ? indicate more digits of the fraction of a second. The type II burst we are interested in started around 15:43 UT on 2023 July 28, which is MJD 060154, so the file we want is <code>/nas5/ovro-lwa-data/beam/beam-data/202307/beam20230728/060153_152717110834334d2be</code>, which starts at 15:27:17 UT. Generally these files contain 30 min of data. The type II continues into the next file, which is <code>060153_1558172229518804396</code>.

To read and display this file, in iPython type
[[File:20230728-type-II.png|300px|left|'''2023 July 28 Type II event spectrogram''']] <pre>
import sys # If not already loaded
sys.path.append('/nas5/ovro-lwa-data/beam/software/')
from lwa import lwa_read, lwa_plot
datadir = '/nas5/ovro-lwa-data/beam/beam-data/202307/beam20230728/'
data = lwa_read(datadir+'060153_152717110834334d2be', stokes='IV', timebin=1, freqbin=4)
lwa_plot(data, vmax=15000,vmin=10)
</pre>
which defaults to log-scaled amplitudes and viridis color table for stokes I and linear-scaled amplitudes and grayscale for stokes V, as shown at left. You can examine lwa_plot? for more options. 
 
 

==Calibration and Imaging Script==
The script below assumes some previous setup. First, a "home" directory needs to be created and the script must be run from that directory. Because of the large amount of disk space required, create your "home" directory on /data1. Mine is /data1/dgary/OVRO-LWA/20230728_workdir. Before running the script, you'll need to change the 7 lines indicated with the '''***Change''' comments.
# The first such line is the list of frequency bands you want to image. In this case I have all 13 useful bands. Frequencies below 27 MHz rarely image well and in many cases we did not save the data for those frequencies anyway.
# The second is a string representing the date of the event, including an underscore (this is part of a filename).
# The third line is a list of solar times. These times have to exactly match existing filenames, so you'll have to do a listing of the data directory to check them. ''Warning: Doing a listing of the entire data directory is time consuming and not useful, since there are many thousands of files there.'' Instead, use something like: <code>ls /nas5/ovro-lwa-data/20230728/slow/20230728_1553*</code> to limit the number of files returned.
# The fourth line is the date string of the calibration data. This will almost always be the same as the date string of the data, but it is possible to use a calibration from a different date if not too far apart.
# The fifth line is the time of the calibration data. Again, this must exist. Usually the calibration is done at night so the time will be quite different, e.g. 0500 UT, and a command like <code>ls /nas5/ovro-lwa-data/20230728/slow | head -20</code> will list the first 20 files in the folder, which are likely the calibration files. Unfortunately, no nighttime calibration exists for this date, so I had to use a daytime time, 15:40 UT.
# The sixth line is the path to the data.
# The seventh line is the path to the calibration data, again usually the same as that for the data.
<pre>
import os, glob
from ovrolwasolar import solar_pipeline, utils
from time import time

freqs=[27,32,36,41,46,50,55,59,64,69,73,78,82] # ***Change to the bands you want to image
datstr = '20230728_' # ***Change to the date of your event
solar_times = ['155306','155316','155326'] # ***Change to the times to use for solar imaging -- these times must exist!
caldatstr = '20230728_' # ***Change to the date of your cal data
cal_time = '154003' # ***Change to the time for your calibration
datapath = '/nas5/ovro-lwa-data/20230728/slow/' # ***Change to path to your data
calpath = '/nas5/ovro-lwa-data/20230728/slow/' # ***Change to path to your calibration data

home=os.getcwd()
for solar_time in solar_times:
for freq in freqs:
calib_ms=caldatstr+cal_time+'_'+str(freq)+"MHz.ms" # Will be copied from calpath
solar_ms=datstr+solar_time+'_'+str(freq)+"MHz.ms" # Will be copied from datapath
bcal='caltables/'+calib_ms.replace('ms','bcal') # Will be created if it doesn't already exist
imagename=datstr+solar_time+'_'+str(freq)+"MHz"
image_fold = 'images/'

# Create frequency folder, if it doesn't exist
freq_fold=str(freq)+"MHz"
if not os.path.isdir(freq_fold):
os.mkdir(freq_fold)

# Copy the solar data for this time (will be deleted later)
print('Copying solar data to frequency folder')
os.system("cp -r "+os.path.join(datapath,solar_ms)+"* "+freq_fold+"/")
# Copy the calibration data (will be deleted later)
print('Copying calibration data to frequency folder')
os.system("cp -r "+os.path.join(calpath,calib_ms)+"* "+freq_fold+"/")

os.chdir(freq_fold)
if not os.path.isdir(image_fold):
os.mkdir(image_fold)
if not os.path.isfile(bcal):
bcal = None
if not os.path.isdir('caltables'):
os.mkdir('caltables')
if not os.path.isdir('final_ms'):
os.mkdir('final_ms')

try:
solar_pipeline.image_ms(solar_ms=solar_ms,calib_ms=calib_ms,bcal=bcal,\
imagename=imagename,do_final_imaging=False,logfile='analysis_'+str(freq)+'.log')
msname = datstr+solar_time+'_'+str(freq)+'MHz_final.ms'
os.system("mv *calibrated_selfcalibrated_sun_only_sun_selfcalibrated_sun_only.ms final_ms/"+msname)
os.system("rm -rf *.ms* *.fits *.gcal *.cl *.badants")
# Make 10 images for this band (integrates over 19 or 20 subchannels, bandwidth ~0.4545 MHz)
#os.system('wsclean -no-dirty -size 1024 1024 -scale 1arcmin -weight uniform -minuv-l 10 -name '+imagename+' -niter 10000 -mgain 0.8 -beam-fitting-size 1 -pol I -join-channels -channels-out 10 final_ms/'+msname)
# Convert images to heliocentric, move them to the final image folder, and delete all fits files
#files = glob.glob('*-image.fits')
#for imgfile in files:
# #utils.correct_primary_beam('final_ms/'+msname, imgfile.split('-image.fits')[0])
# helio_image = utils.convert_to_heliocentric_coords('final_ms/'+msname, imgfile)
# os.system('mv '+helio_image+' '+image_fold)
#os.system('rm *.fits')
except:
pass
os.chdir(home)

</pre>

After the final ms's are created, run the code below to create fits-wrapped image cubes of the data.
<pre>
from solar_realtime_pipeline import run_imager
from suncasa.utils import helioimage2fits as hf
from suncasa.io import ndfits
from astropy.time import Time
import glob
import os

freqs = [27,32,36,41,46,50,55,59,64,69,73,78,82] # ***Change to the bands you want to image
solar_times = ['192030'] # ***Change to the times to use for solar imaging -- these times must exist!
datstr = '20231009_' # ***Change to the date of your event
for solar_time in solar_times:
tref = Time(datstr[:4]+'-'+datstr[4:6]+'-'+datstr[6:]+' '+solar_time[:2]+':'+solar_time[2:4]+':'+solar_time[4:])
ephem = hf.read_horizons(tref, dur=1./60./24., observatory='OVRO_MMA')
if not os.path.exists('imagedir_allch'):
os.makedirs('imagedir_allch')
if not os.path.exists('fits'):
os.makedirs('fits')
outfits_helio = []
# Make all the images (by calling run_imager)
for freq in freqs:
folder = str(freq)+'MHz'
msname = folder+'/final_ms/'+datstr+solar_time+'_'+str(freq)+'MHz_final.ms'
outfits_helio += run_imager(msname, imagedir_allch='imagedir_allch/', ephem=ephem)

fitsfiles_mfs = []
fitsfiles_fch = []
for f in outfits_helio:
if 'MFS' in f:
fitsfiles_mfs.append(f)
else:
fitsfiles_fch.append(f)
## Wrap images
timestr_iso = tref.isot[:-4].replace(':','')+'Z'
fits_mfs = 'fits/ovro-lwa.lev1_mfs_10s.' + timestr_iso + '.image.fits'
fits_fch = 'fits/ovro-lwa.lev1_fch_10s.' + timestr_iso + '.image.fits'
# multi-frequency synthesis images
fitsfiles_mfs.sort()
ndfits.wrap(fitsfiles_mfs, outfitsfile=fits_mfs)

# fine channel spectral images
fitsfiles_fch.sort()
ndfits.wrap(fitsfiles_fch, outfitsfile=fits_fch)
</pre>

== What Happens When You Run the Script ==
One way to run these scripts is to cut-and-paste the first script into a file, say process.py, cut-and-paste the second script into another file, say mk_imgs.py, and then in an iPython session type
<pre>
import sys
sys.path.append('/home/dgary/ovro-lwa-solar') # Change to your path where you cloned the git repository
run 'process.py' # Wait until all final ms's are created--could take many hours!
run 'mk_imgs.py'
</pre>
If all goes well, after many hours you will have all of your images. If you examine the script, you will see that there are two loops, an inner one over frequency and an outer one over time. The inner loop will create a subdirectory for the frequency it is working on (first will be subdirectory named 27MHz), then do the calibration for that frequency and create a subfolder caltables with a .bcal file in it. Luckily, this only has to be done once and then the .bcal file will be used for subsequent times so its creation will be skipped. Other files with .gcal extension will be created for the first data time, and also will be reused for subesquent times up to one hour later. When a new .gcal file is needed, the pipeline will create it automatically for you. The gain files take about 10 min for each frequency, but again is only done once for an hour of data. After the calibration is complete, <code>wsclean</code> is used to create images (in 10 subbands of each 4.5 GHz band, plus an MFS image integrated over the whole band). They are converted to heliographic coordinates and you will find them in 27MHz/images when done. This takes another 10 minutes or so.

When all of that is done for the first frequency, the whole process starts again for the next, and so one until all images for the first time are done. In this example, then, it will take about 20/min per frequency * 13 frequencies = 260 minutes (> 4 hours!) to make all 143 images for the first time (10 images per band + 1 MFS image). For subsequent times, though, the calibration step is skipped so each subsequent time will take 10 min * 13 frequencies (around 2 hours). That means the entire script will run in about 8 hours and produce 429 images.

Tohban OVRO-LWA Imaging Tutorial

2024-01-16T15:26:29Z

Dgary: /* Calibration and Imaging Script */

=Initial Setup=
The OVRO-LWA has three solar modes that can operate concurrently. These are (1) the beamformer, which creates a high-resolution spectrogram of the solar activity each day, (2) a slow visibility mode that records data in CASA ms format for all 352 antennas and all 3072 frequencies at 10-s cadence, and (3) a fast visibility mode that records data for a 48-antenna subset (generally the outer antennas) and 768 frequencies at 1-s cadence. The recorders that record the data are all activated separately, so it is not guaranteed that data from all three modes are available at any one time. Also, because of the vast data volume most of the recorded data are not saved, but rather are overwritten after a day or so, hence any data that are wanted must be explicitly saved by copying it to another location. Again because of the large volume of data, such copying is too slow to save much data (at least at present), so we can generally save only about an hour of data per day.

'''Note: This tutorial only describes how to work with the slow visibility data at the moment.'''

==Python Environment==
The imaging pipeline is written in Python 3, so in order to use it one must set up a Python 3 environment. These instructions assume you are working in your own home directory on the Pipeline machine at OVRO. First enter the bash shell if you are not already in it. Type <code>echo $0</code> to see what shell you are in. If that returns something other than -bash, type <code>bash</code> to enter the shell. Next check if you have the line <code>alias loadpyenv3.8='source /home/user/.setenv_pyenv38'</code> in your ~/.bash_aliases file. If not, add it using your favorite editor, then activate it with <code>source ~/.bash_aliases</code>. From there, you can type <code>loadpyenv3.8</code> to enter the Python 3.8 environment. Finally, from your home folder, type <code> git clone https://github.com/binchensun/ovro-lwa-solar </code> to install the OVRO-LWA code. To test your Python environment, log out and log in again fresh, then type
<pre>
$> loadpyenv3.8
$> ipython --pylab
import sys
sys.path.append('/home/dgary/ovro-lwa-solar') # Replace with your own home directory
from ovrolwasolar import solar_pipeline
</pre>
If that succeeds, you should be ready to proceed.

==Where to Find Data==
The next step is to find the data you want to work with. You will need some calibration data as well as the solar data for your target date. As of this writing, the existing solar data on Pipeline, is in two separate places: /nas5/ovro-lwa-data (data up to 2023-09-03) and /nas6/ovro-lwa-data (data from 2023-09-18 and later). All of the existing beamformed data (spectrograms) are in /nas5/ovro-lwa-data/beam/beam-data.

'''This tutorial uses the example of the type II burst on 2023-07-28.'''

==Examining the Spectrogram for Your Date==
It is good practice to examine the spectrogram for your date/time, to guide your selection of frequencies and times to use for imaging. You can check the folders and subfolders in /nas5/ovro-lwa-data/beam/beam-data to see what files exist. Note that the filenames have the Modified Julian Data (mjd) followed by hours, minutes, seconds in the format <mjdday>.<hh><mm><ss>?????????? where the ? indicate more digits of the fraction of a second. The type II burst we are interested in started around 15:43 UT on 2023 July 28, which is MJD 060154, so the file we want is <code>/nas5/ovro-lwa-data/beam/beam-data/202307/beam20230728/060153_152717110834334d2be</code>, which starts at 15:27:17 UT. Generally these files contain 30 min of data. The type II continues into the next file, which is <code>060153_1558172229518804396</code>.

To read and display this file, in iPython type
[[File:20230728-type-II.png|300px|left|'''2023 July 28 Type II event spectrogram''']] <pre>
import sys # If not already loaded
sys.path.append('/nas5/ovro-lwa-data/beam/software/')
from lwa import lwa_read, lwa_plot
datadir = '/nas5/ovro-lwa-data/beam/beam-data/202307/beam20230728/'
data = lwa_read(datadir+'060153_152717110834334d2be', stokes='IV', timebin=1, freqbin=4)
lwa_plot(data, vmax=15000,vmin=10)
</pre>
which defaults to log-scaled amplitudes and viridis color table for stokes I and linear-scaled amplitudes and grayscale for stokes V, as shown at left. You can examine lwa_plot? for more options. 
 
 

==Calibration and Imaging Script==
The script below assumes some previous setup. First, a "home" directory needs to be created and the script must be run from that directory. Because of the large amount of disk space required, create your "home" directory on /data1. Mine is /data1/dgary/OVRO-LWA/20230728_workdir. Before running the script, you'll need to change the 7 lines indicated with the '''***Change''' comments.
# The first such line is the list of frequency bands you want to image. In this case I have all 13 useful bands. Frequencies below 27 MHz rarely image well and in many cases we did not save the data for those frequencies anyway.
# The second is a string representing the date of the event, including an underscore (this is part of a filename).
# The third line is a list of solar times. These times have to exactly match existing filenames, so you'll have to do a listing of the data directory to check them. ''Warning: Doing a listing of the entire data directory is time consuming and not useful, since there are many thousands of files there.'' Instead, use something like: <code>ls /nas5/ovro-lwa-data/20230728/slow/20230728_1553*</code> to limit the number of files returned.
# The fourth line is the date string of the calibration data. This will almost always be the same as the date string of the data, but it is possible to use a calibration from a different date if not too far apart.
# The fifth line is the time of the calibration data. Again, this must exist. Usually the calibration is done at night so the time will be quite different, e.g. 0500 UT, and a command like <code>ls /nas5/ovro-lwa-data/20230728/slow | head -20</code> will list the first 20 files in the folder, which are likely the calibration files. Unfortunately, no nighttime calibration exists for this date, so I had to use a daytime time, 15:40 UT.
# The sixth line is the path to the data.
# The seventh line is the path to the calibration data, again usually the same as that for the data.
<pre>
import os, glob
from ovrolwasolar import solar_pipeline, utils
from time import time

freqs=[27,32,36,41,46,50,55,59,64,69,73,78,82] # ***Change to the bands you want to image
datstr = '20230728_' # ***Change to the date of your event
solar_times = ['155306','155316','155326'] # ***Change to the times to use for solar imaging -- these times must exist!
caldatstr = '20230728_' # ***Change to the date of your cal data
cal_time = '154003' # ***Change to the time for your calibration
datapath = '/nas5/ovro-lwa-data/20230728/slow/' # ***Change to path to your data
calpath = '/nas5/ovro-lwa-data/20230728/slow/' # ***Change to path to your calibration data

home=os.getcwd()
for solar_time in solar_times:
for freq in freqs:
calib_ms=caldatstr+cal_time+'_'+str(freq)+"MHz.ms" # Will be copied from calpath
solar_ms=datstr+solar_time+'_'+str(freq)+"MHz.ms" # Will be copied from datapath
bcal='caltables/'+calib_ms.replace('ms','bcal') # Will be created if it doesn't already exist
imagename=datstr+solar_time+'_'+str(freq)+"MHz"
image_fold = 'images/'

# Create frequency folder, if it doesn't exist
freq_fold=str(freq)+"MHz"
if not os.path.isdir(freq_fold):
os.mkdir(freq_fold)

# Copy the solar data for this time (will be deleted later)
print('Copying solar data to frequency folder')
os.system("cp -r "+os.path.join(datapath,solar_ms)+"* "+freq_fold+"/")
# Copy the calibration data (will be deleted later)
print('Copying calibration data to frequency folder')
os.system("cp -r "+os.path.join(calpath,calib_ms)+"* "+freq_fold+"/")

os.chdir(freq_fold)
if not os.path.isdir(image_fold):
os.mkdir(image_fold)
if not os.path.isfile(bcal):
bcal = None
if not os.path.isdir('caltables'):
os.mkdir('caltables')
if not os.path.isdir('final_ms'):
os.mkdir('final_ms')

try:
solar_pipeline.image_ms(solar_ms=solar_ms,calib_ms=calib_ms,bcal=bcal,\
imagename=imagename,do_final_imaging=False,logfile='analysis_'+str(freq)+'.log')
msname = datstr+solar_time+'_'+str(freq)+'MHz_final.ms'
os.system("mv *calibrated_selfcalibrated_sun_only_sun_selfcalibrated_sun_only.ms final_ms/"+msname)
os.system("rm -rf *.ms* *.fits *.gcal *.cl *.badants")
# Make 10 images for this band (integrates over 19 or 20 subchannels, bandwidth ~0.4545 MHz)
#os.system('wsclean -no-dirty -size 1024 1024 -scale 1arcmin -weight uniform -minuv-l 10 -name '+imagename+' -niter 10000 -mgain 0.8 -beam-fitting-size 1 -pol I -join-channels -channels-out 10 final_ms/'+msname)
# Convert images to heliocentric, move them to the final image folder, and delete all fits files
#files = glob.glob('*-image.fits')
#for imgfile in files:
# #utils.correct_primary_beam('final_ms/'+msname, imgfile.split('-image.fits')[0])
# helio_image = utils.convert_to_heliocentric_coords('final_ms/'+msname, imgfile)
# os.system('mv '+helio_image+' '+image_fold)
#os.system('rm *.fits')
except:
pass
os.chdir(home)

</pre>

After the final ms's are created, run the code below to create fits-wrapped image cubes of the data.
<pre>
from solar_realtime_pipeline import run_imager
from suncasa.utils import helioimage2fits as hf
from suncasa.io import ndfits
from astropy.time import Time
import glob
import os

freqs = [27,32,36,41,46,50,55,59,64,69,73,78,82] # ***Change to the bands you want to image
solar_times = ['192030'] # ***Change to the times to use for solar imaging -- these times must exist!
datstr = '20231009_' # ***Change to the date of your event
for solar_time in solar_times:
tref = Time(datstr[:4]+'-'+datstr[4:6]+'-'+datstr[6:]+' '+solar_time[:2]+':'+solar_time[2:4]+':'+solar_time[4:])
ephem = hf.read_horizons(tref, dur=1./60./24., observatory='OVRO_MMA')
if not os.path.exists('imagedir_allch'):
os.makedirs('imagedir_allch')
if not os.path.exists('fits'):
os.makedirs('fits')
outfits_helio = []
# Make all the images (by calling run_imager)
for freq in freqs:
folder = str(freq)+'MHz'
msname = folder+'/final_ms/'+datstr+solar_time+'_'+str(freq)+'MHz_final.ms'
outfits_helio += run_imager(msname, imagedir_allch='imagedir_allch/', ephem=ephem)

fitsfiles_mfs = []
fitsfiles_fch = []
for f in outfits_helio:
if 'MFS' in f:
fitsfiles_mfs.append(f)
else:
fitsfiles_fch.append(f)
## Wrap images
timestr_iso = tref.isot[:-4].replace(':','')+'Z'
fits_mfs = 'fits/ovro-lwa.lev1_mfs_10s.' + timestr_iso + '.image.fits'
fits_fch = 'fits/ovro-lwa.lev1_fch_10s.' + timestr_iso + '.image.fits'
# multi-frequency synthesis images
fitsfiles_mfs.sort()
ndfits.wrap(fitsfiles_mfs, outfitsfile=fits_mfs)

# fine channel spectral images
fitsfiles_fch.sort()
ndfits.wrap(fitsfiles_fch, outfitsfile=fits_fch)
</pre>

== What Happens When You Run the Script ==
One way to run this script is to cut-and-paste into a file, say process.py, and then in an iPython session type
<pre>
import sys
sys.path.append('/home/dgary/ovro-lwa-solar') # Change to your path where you cloned the git repository
run 'process.py'
</pre>
If all goes well, after many hours you will have all of your images. If you examine the script, you will see that there are two loops, an inner one over frequency and an outer one over time. The inner loop will create a subdirectory for the frequency it is working on (first will be subdirectory named 27MHz), then do the calibration for that frequency and create a subfolder caltables with a .bcal file in it. Luckily, this only has to be done once and then the .bcal file will be used for subsequent times so its creation will be skipped. Other files with .gcal extension will be created for the first data time, and also will be reused for subesquent times up to one hour later. When a new .gcal file is needed, the pipeline will create it automatically for you. The gain files take about 10 min for each frequency, but again is only done once for an hour of data. After the calibration is complete, <code>wsclean</code> is used to create images (in 10 subbands of each 4.5 GHz band, plus an MFS image integrated over the whole band). They are converted to heliographic coordinates and you will find them in 27MHz/images when done. This takes another 10 minutes or so.

When all of that is done for the first frequency, the whole process starts again for the next, and so one until all images for the first time are done. In this example, then, it will take about 20/min per frequency * 13 frequencies = 260 minutes (> 4 hours!) to make all 143 images for the first time (10 images per band + 1 MFS image). For subsequent times, though, the calibration step is skipped so each subsequent time will take 10 min * 13 frequencies (around 2 hours). That means the entire script will run in about 8 hours and produce 429 images.

Tohban OVRO-LWA Imaging Tutorial

2024-01-16T15:24:38Z

Dgary: /* Calibration and Imaging Script */

=Initial Setup=
The OVRO-LWA has three solar modes that can operate concurrently. These are (1) the beamformer, which creates a high-resolution spectrogram of the solar activity each day, (2) a slow visibility mode that records data in CASA ms format for all 352 antennas and all 3072 frequencies at 10-s cadence, and (3) a fast visibility mode that records data for a 48-antenna subset (generally the outer antennas) and 768 frequencies at 1-s cadence. The recorders that record the data are all activated separately, so it is not guaranteed that data from all three modes are available at any one time. Also, because of the vast data volume most of the recorded data are not saved, but rather are overwritten after a day or so, hence any data that are wanted must be explicitly saved by copying it to another location. Again because of the large volume of data, such copying is too slow to save much data (at least at present), so we can generally save only about an hour of data per day.

'''Note: This tutorial only describes how to work with the slow visibility data at the moment.'''

==Python Environment==
The imaging pipeline is written in Python 3, so in order to use it one must set up a Python 3 environment. These instructions assume you are working in your own home directory on the Pipeline machine at OVRO. First enter the bash shell if you are not already in it. Type <code>echo $0</code> to see what shell you are in. If that returns something other than -bash, type <code>bash</code> to enter the shell. Next check if you have the line <code>alias loadpyenv3.8='source /home/user/.setenv_pyenv38'</code> in your ~/.bash_aliases file. If not, add it using your favorite editor, then activate it with <code>source ~/.bash_aliases</code>. From there, you can type <code>loadpyenv3.8</code> to enter the Python 3.8 environment. Finally, from your home folder, type <code> git clone https://github.com/binchensun/ovro-lwa-solar </code> to install the OVRO-LWA code. To test your Python environment, log out and log in again fresh, then type
<pre>
$> loadpyenv3.8
$> ipython --pylab
import sys
sys.path.append('/home/dgary/ovro-lwa-solar') # Replace with your own home directory
from ovrolwasolar import solar_pipeline
</pre>
If that succeeds, you should be ready to proceed.

==Where to Find Data==
The next step is to find the data you want to work with. You will need some calibration data as well as the solar data for your target date. As of this writing, the existing solar data on Pipeline, is in two separate places: /nas5/ovro-lwa-data (data up to 2023-09-03) and /nas6/ovro-lwa-data (data from 2023-09-18 and later). All of the existing beamformed data (spectrograms) are in /nas5/ovro-lwa-data/beam/beam-data.

'''This tutorial uses the example of the type II burst on 2023-07-28.'''

==Examining the Spectrogram for Your Date==
It is good practice to examine the spectrogram for your date/time, to guide your selection of frequencies and times to use for imaging. You can check the folders and subfolders in /nas5/ovro-lwa-data/beam/beam-data to see what files exist. Note that the filenames have the Modified Julian Data (mjd) followed by hours, minutes, seconds in the format <mjdday>.<hh><mm><ss>?????????? where the ? indicate more digits of the fraction of a second. The type II burst we are interested in started around 15:43 UT on 2023 July 28, which is MJD 060154, so the file we want is <code>/nas5/ovro-lwa-data/beam/beam-data/202307/beam20230728/060153_152717110834334d2be</code>, which starts at 15:27:17 UT. Generally these files contain 30 min of data. The type II continues into the next file, which is <code>060153_1558172229518804396</code>.

To read and display this file, in iPython type
[[File:20230728-type-II.png|300px|left|'''2023 July 28 Type II event spectrogram''']] <pre>
import sys # If not already loaded
sys.path.append('/nas5/ovro-lwa-data/beam/software/')
from lwa import lwa_read, lwa_plot
datadir = '/nas5/ovro-lwa-data/beam/beam-data/202307/beam20230728/'
data = lwa_read(datadir+'060153_152717110834334d2be', stokes='IV', timebin=1, freqbin=4)
lwa_plot(data, vmax=15000,vmin=10)
</pre>
which defaults to log-scaled amplitudes and viridis color table for stokes I and linear-scaled amplitudes and grayscale for stokes V, as shown at left. You can examine lwa_plot? for more options. 
 
 

==Calibration and Imaging Script==
The script below assumes some previous setup. First, a "home" directory needs to be created and the script must be run from that directory. Because of the large amount of disk space required, create your "home" directory on /data1. Mine is /data1/dgary/OVRO-LWA/20230728_workdir. Before running the script, you'll need to change the 7 lines indicated with the '''***Change''' comments.
# The first such line is the list of frequency bands you want to image. In this case I have all 13 useful bands. Frequencies below 27 MHz rarely image well and in many cases we did not save the data for those frequencies anyway.
# The second is a string representing the date of the event, including an underscore (this is part of a filename).
# The third line is a list of solar times. These times have to exactly match existing filenames, so you'll have to do a listing of the data directory to check them. ''Warning: Doing a listing of the entire data directory is time consuming and not useful, since there are many thousands of files there.'' Instead, use something like: <code>ls /nas5/ovro-lwa-data/20230728/slow/20230728_1553*</code> to limit the number of files returned.
# The fourth line is the date string of the calibration data. This will almost always be the same as the date string of the data, but it is possible to use a calibration from a different date if not too far apart.
# The fifth line is the time of the calibration data. Again, this must exist. Usually the calibration is done at night so the time will be quite different, e.g. 0500 UT, and a command like <code>ls /nas5/ovro-lwa-data/20230728/slow | head -20</code> will list the first 20 files in the folder, which are likely the calibration files. Unfortunately, no nighttime calibration exists for this date, so I had to use a daytime time, 15:40 UT.
# The sixth line is the path to the data.
# The seventh line is the path to the calibration data, again usually the same as that for the data.
<pre>
import os, glob
from ovrolwasolar import solar_pipeline, utils
from time import time

freqs=[27,32,36,41,46,50,55,59,64,69,73,78,82] # ***Change to the bands you want to image
datstr = '20230728_' # ***Change to the date of your event
solar_times = ['155306','155316','155326'] # ***Change to the times to use for solar imaging -- these times must exist!
caldatstr = '20230728_' # ***Change to the date of your cal data
cal_time = '154003' # ***Change to the time for your calibration
datapath = '/nas5/ovro-lwa-data/20230728/slow/' # ***Change to path to your data
calpath = '/nas5/ovro-lwa-data/20230728/slow/' # ***Change to path to your calibration data

home=os.getcwd()
for solar_time in solar_times:
for freq in freqs:
calib_ms=caldatstr+cal_time+'_'+str(freq)+"MHz.ms" # Will be copied from calpath
solar_ms=datstr+solar_time+'_'+str(freq)+"MHz.ms" # Will be copied from datapath
bcal='caltables/'+calib_ms.replace('ms','bcal') # Will be created if it doesn't already exist
imagename=datstr+solar_time+'_'+str(freq)+"MHz"
image_fold = 'images/'

# Create frequency folder, if it doesn't exist
freq_fold=str(freq)+"MHz"
if not os.path.isdir(freq_fold):
os.mkdir(freq_fold)

# Copy the solar data for this time (will be deleted later)
print('Copying solar data to frequency folder')
os.system("cp -r "+os.path.join(datapath,solar_ms)+"* "+freq_fold+"/")
# Copy the calibration data (will be deleted later)
print('Copying calibration data to frequency folder')
os.system("cp -r "+os.path.join(calpath,calib_ms)+"* "+freq_fold+"/")

os.chdir(freq_fold)
if not os.path.isdir(image_fold):
os.mkdir(image_fold)
if not os.path.isfile(bcal):
bcal = None
if not os.path.isdir('caltables'):
os.mkdir('caltables')
if not os.path.isdir('final_ms'):
os.mkdir('final_ms')

try:
solar_pipeline.image_ms(solar_ms=solar_ms,calib_ms=calib_ms,bcal=bcal,\
imagename=imagename,do_final_imaging=False,logfile='analysis_'+str(freq)+'.log')
msname = datstr+solar_time+'_'+str(freq)+'MHz_final.ms'
os.system("mv *calibrated_selfcalibrated_sun_only_sun_selfcalibrated_sun_only.ms final_ms/"+msname)
os.system("rm -rf *.ms* *.fits *.gcal *.cl *.badants")
# Make 10 images for this band (integrates over 19 or 20 subchannels, bandwidth ~0.4545 MHz)
#os.system('wsclean -no-dirty -size 1024 1024 -scale 1arcmin -weight uniform -minuv-l 10 -name '+imagename+' -niter 10000 -mgain 0.8 -beam-fitting-size 1 -pol I -join-channels -channels-out 10 final_ms/'+msname)
# Convert images to heliocentric, move them to the final image folder, and delete all fits files
#files = glob.glob('*-image.fits')
#for imgfile in files:
# #utils.correct_primary_beam('final_ms/'+msname, imgfile.split('-image.fits')[0])
# helio_image = utils.convert_to_heliocentric_coords('final_ms/'+msname, imgfile)
# os.system('mv '+helio_image+' '+image_fold)
#os.system('rm *.fits')
except:
pass
os.chdir(home)

</pre>

After the final ms's are created, run the code below to create fits-wrapped image cubes of the data.
<pre>
import sys
sys.path.append('/home/dgary/ovro-lwa-solar') # ***Change to your folder (or wherever you cloned ovro-lwa-solar)
from solar_realtime_pipeline import run_imager
from suncasa.utils import helioimage2fits as hf
from suncasa.io import ndfits
from astropy.time import Time
import glob
import os

freqs = [27,32,36,41,46,50,55,59,64,69,73,78,82] # ***Change to the bands you want to image
solar_times = ['192030'] # ***Change to the times to use for solar imaging -- these times must exist!
datstr = '20231009_' # ***Change to the date of your event
for solar_time in solar_times:
tref = Time(datstr[:4]+'-'+datstr[4:6]+'-'+datstr[6:]+' '+solar_time[:2]+':'+solar_time[2:4]+':'+solar_time[4:])
ephem = hf.read_horizons(tref, dur=1./60./24., observatory='OVRO_MMA')
if not os.path.exists('imagedir_allch'):
os.makedirs('imagedir_allch')
if not os.path.exists('fits'):
os.makedirs('fits')
outfits_helio = []
# Make all the images (by calling run_imager)
for freq in freqs:
folder = str(freq)+'MHz'
msname = folder+'/final_ms/'+datstr+solar_time+'_'+str(freq)+'MHz_final.ms'
outfits_helio += run_imager(msname, imagedir_allch='imagedir_allch/', ephem=ephem)

fitsfiles_mfs = []
fitsfiles_fch = []
for f in outfits_helio:
if 'MFS' in f:
fitsfiles_mfs.append(f)
else:
fitsfiles_fch.append(f)
## Wrap images
timestr_iso = tref.isot[:-4].replace(':','')+'Z'
fits_mfs = 'fits/ovro-lwa.lev1_mfs_10s.' + timestr_iso + '.image.fits'
fits_fch = 'fits/ovro-lwa.lev1_fch_10s.' + timestr_iso + '.image.fits'
# multi-frequency synthesis images
fitsfiles_mfs.sort()
ndfits.wrap(fitsfiles_mfs, outfitsfile=fits_mfs)

# fine channel spectral images
fitsfiles_fch.sort()
ndfits.wrap(fitsfiles_fch, outfitsfile=fits_fch)
</pre>

== What Happens When You Run the Script ==
One way to run this script is to cut-and-paste into a file, say process.py, and then in an iPython session type
<pre>
import sys
sys.path.append('/home/dgary/ovro-lwa-solar') # Change to your path where you cloned the git repository
run 'process.py'
</pre>
If all goes well, after many hours you will have all of your images. If you examine the script, you will see that there are two loops, an inner one over frequency and an outer one over time. The inner loop will create a subdirectory for the frequency it is working on (first will be subdirectory named 27MHz), then do the calibration for that frequency and create a subfolder caltables with a .bcal file in it. Luckily, this only has to be done once and then the .bcal file will be used for subsequent times so its creation will be skipped. Other files with .gcal extension will be created for the first data time, and also will be reused for subesquent times up to one hour later. When a new .gcal file is needed, the pipeline will create it automatically for you. The gain files take about 10 min for each frequency, but again is only done once for an hour of data. After the calibration is complete, <code>wsclean</code> is used to create images (in 10 subbands of each 4.5 GHz band, plus an MFS image integrated over the whole band). They are converted to heliographic coordinates and you will find them in 27MHz/images when done. This takes another 10 minutes or so.

When all of that is done for the first frequency, the whole process starts again for the next, and so one until all images for the first time are done. In this example, then, it will take about 20/min per frequency * 13 frequencies = 260 minutes (> 4 hours!) to make all 143 images for the first time (10 images per band + 1 MFS image). For subsequent times, though, the calibration step is skipped so each subsequent time will take 10 min * 13 frequencies (around 2 hours). That means the entire script will run in about 8 hours and produce 429 images.

Tohban OVRO-LWA Imaging Tutorial

2024-01-16T15:23:35Z

Dgary: /* Calibration and Imaging Script */

=Initial Setup=
The OVRO-LWA has three solar modes that can operate concurrently. These are (1) the beamformer, which creates a high-resolution spectrogram of the solar activity each day, (2) a slow visibility mode that records data in CASA ms format for all 352 antennas and all 3072 frequencies at 10-s cadence, and (3) a fast visibility mode that records data for a 48-antenna subset (generally the outer antennas) and 768 frequencies at 1-s cadence. The recorders that record the data are all activated separately, so it is not guaranteed that data from all three modes are available at any one time. Also, because of the vast data volume most of the recorded data are not saved, but rather are overwritten after a day or so, hence any data that are wanted must be explicitly saved by copying it to another location. Again because of the large volume of data, such copying is too slow to save much data (at least at present), so we can generally save only about an hour of data per day.

'''Note: This tutorial only describes how to work with the slow visibility data at the moment.'''

==Python Environment==
The imaging pipeline is written in Python 3, so in order to use it one must set up a Python 3 environment. These instructions assume you are working in your own home directory on the Pipeline machine at OVRO. First enter the bash shell if you are not already in it. Type <code>echo $0</code> to see what shell you are in. If that returns something other than -bash, type <code>bash</code> to enter the shell. Next check if you have the line <code>alias loadpyenv3.8='source /home/user/.setenv_pyenv38'</code> in your ~/.bash_aliases file. If not, add it using your favorite editor, then activate it with <code>source ~/.bash_aliases</code>. From there, you can type <code>loadpyenv3.8</code> to enter the Python 3.8 environment. Finally, from your home folder, type <code> git clone https://github.com/binchensun/ovro-lwa-solar </code> to install the OVRO-LWA code. To test your Python environment, log out and log in again fresh, then type
<pre>
$> loadpyenv3.8
$> ipython --pylab
import sys
sys.path.append('/home/dgary/ovro-lwa-solar') # Replace with your own home directory
from ovrolwasolar import solar_pipeline
</pre>
If that succeeds, you should be ready to proceed.

==Where to Find Data==
The next step is to find the data you want to work with. You will need some calibration data as well as the solar data for your target date. As of this writing, the existing solar data on Pipeline, is in two separate places: /nas5/ovro-lwa-data (data up to 2023-09-03) and /nas6/ovro-lwa-data (data from 2023-09-18 and later). All of the existing beamformed data (spectrograms) are in /nas5/ovro-lwa-data/beam/beam-data.

'''This tutorial uses the example of the type II burst on 2023-07-28.'''

==Examining the Spectrogram for Your Date==
It is good practice to examine the spectrogram for your date/time, to guide your selection of frequencies and times to use for imaging. You can check the folders and subfolders in /nas5/ovro-lwa-data/beam/beam-data to see what files exist. Note that the filenames have the Modified Julian Data (mjd) followed by hours, minutes, seconds in the format <mjdday>.<hh><mm><ss>?????????? where the ? indicate more digits of the fraction of a second. The type II burst we are interested in started around 15:43 UT on 2023 July 28, which is MJD 060154, so the file we want is <code>/nas5/ovro-lwa-data/beam/beam-data/202307/beam20230728/060153_152717110834334d2be</code>, which starts at 15:27:17 UT. Generally these files contain 30 min of data. The type II continues into the next file, which is <code>060153_1558172229518804396</code>.

To read and display this file, in iPython type
[[File:20230728-type-II.png|300px|left|'''2023 July 28 Type II event spectrogram''']] <pre>
import sys # If not already loaded
sys.path.append('/nas5/ovro-lwa-data/beam/software/')
from lwa import lwa_read, lwa_plot
datadir = '/nas5/ovro-lwa-data/beam/beam-data/202307/beam20230728/'
data = lwa_read(datadir+'060153_152717110834334d2be', stokes='IV', timebin=1, freqbin=4)
lwa_plot(data, vmax=15000,vmin=10)
</pre>
which defaults to log-scaled amplitudes and viridis color table for stokes I and linear-scaled amplitudes and grayscale for stokes V, as shown at left. You can examine lwa_plot? for more options. 
 
 

==Calibration and Imaging Script==
The script below assumes some previous setup. First, a "home" directory needs to be created and the script must be run from that directory. Because of the large amount of disk space required, create your "home" directory on /data1. Mine is /data1/dgary/OVRO-LWA/20230728_workdir. Before running the script, you'll need to change the 7 lines indicated with the '''***Change''' comments.
# The first such line is the list of frequency bands you want to image. In this case I have all 13 useful bands. Frequencies below 27 MHz rarely image well and in many cases we did not save the data for those frequencies anyway.
# The second is a string representing the date of the event, including an underscore (this is part of a filename).
# The third line is a list of solar times. These times have to exactly match existing filenames, so you'll have to do a listing of the data directory to check them. ''Warning: Doing a listing of the entire data directory is time consuming and not useful, since there are many thousands of files there.'' Instead, use something like: <code>ls /nas5/ovro-lwa-data/20230728/slow/20230728_1553*</code> to limit the number of files returned.
# The fourth line is the date string of the calibration data. This will almost always be the same as the date string of the data, but it is possible to use a calibration from a different date if not too far apart.
# The fifth line is the time of the calibration data. Again, this must exist. Usually the calibration is done at night so the time will be quite different, e.g. 0500 UT, and a command like <code>ls /nas5/ovro-lwa-data/20230728/slow | head -20</code> will list the first 20 files in the folder, which are likely the calibration files. Unfortunately, no nighttime calibration exists for this date, so I had to use a daytime time, 15:40 UT.
# The sixth line is the path to the data.
# The seventh line is the path to the calibration data, again usually the same as that for the data.
<pre>
import os, glob
from ovrolwasolar import solar_pipeline, utils
from time import time

freqs=[27,32,36,41,46,50,55,59,64,69,73,78,82] # ***Change to the bands you want to image
datstr = '20230728_' # ***Change to the date of your event
solar_times = ['155306','155316','155326'] # ***Change to the times to use for solar imaging -- these times must exist!
caldatstr = '20230728_' # ***Change to the date of your cal data
cal_time = '154003' # ***Change to the time for your calibration
datapath = '/nas5/ovro-lwa-data/20230728/slow/' # ***Change to path to your data
calpath = '/nas5/ovro-lwa-data/20230728/slow/' # ***Change to path to your calibration data

home=os.getcwd()
for solar_time in solar_times:
for freq in freqs:
calib_ms=caldatstr+cal_time+'_'+str(freq)+"MHz.ms" # Will be copied from calpath
solar_ms=datstr+solar_time+'_'+str(freq)+"MHz.ms" # Will be copied from datapath
bcal='caltables/'+calib_ms.replace('ms','bcal') # Will be created if it doesn't already exist
imagename=datstr+solar_time+'_'+str(freq)+"MHz"
image_fold = 'images/'

# Create frequency folder, if it doesn't exist
freq_fold=str(freq)+"MHz"
if not os.path.isdir(freq_fold):
os.mkdir(freq_fold)

# Copy the solar data for this time (will be deleted later)
print('Copying solar data to frequency folder')
os.system("cp -r "+os.path.join(datapath,solar_ms)+"* "+freq_fold+"/")
# Copy the calibration data (will be deleted later)
print('Copying calibration data to frequency folder')
os.system("cp -r "+os.path.join(calpath,calib_ms)+"* "+freq_fold+"/")

os.chdir(freq_fold)
if not os.path.isdir(image_fold):
os.mkdir(image_fold)
if not os.path.isfile(bcal):
bcal = None
if not os.path.isdir('caltables'):
os.mkdir('caltables')
if not os.path.isdir('final_ms'):
os.mkdir('final_ms')

try:
solar_pipeline.image_ms(solar_ms=solar_ms,calib_ms=calib_ms,bcal=bcal,\
imagename=imagename,do_final_imaging=False,logfile='analysis_'+str(freq)+'.log')
msname = datstr+solar_time+'_'+str(freq)+'MHz_final.ms'
os.system("mv *calibrated_selfcalibrated_sun_only_sun_selfcalibrated_sun_only.ms final_ms/"+msname)
os.system("rm -rf *.ms* *.fits *.gcal *.cl *.badants")
# Make 10 images for this band (integrates over 19 or 20 subchannels, bandwidth ~0.4545 MHz)
os.system('wsclean -no-dirty -size 1024 1024 -scale 1arcmin -weight uniform -minuv-l 10 -name '+imagename+' -niter 10000 -mgain 0.8 -beam-fitting-size 1 -pol I -join-channels -channels-out 10 final_ms/'+msname)
# Convert images to heliocentric, move them to the final image folder, and delete all fits files
files = glob.glob('*-image.fits')
for imgfile in files:
#utils.correct_primary_beam('final_ms/'+msname, imgfile.split('-image.fits')[0])
helio_image = utils.convert_to_heliocentric_coords('final_ms/'+msname, imgfile)
os.system('mv '+helio_image+' '+image_fold)
os.system('rm *.fits')
except:
pass
os.chdir(home)

</pre>

After the final ms's are created, run the code below to create fits-wrapped image cubes of the data.
<pre>
import sys
sys.path.append('/home/dgary/ovro-lwa-solar') # ***Change to your folder (or wherever you cloned ovro-lwa-solar)
from solar_realtime_pipeline import run_imager
from suncasa.utils import helioimage2fits as hf
from suncasa.io import ndfits
from astropy.time import Time
import glob
import os

freqs = [27,32,36,41,46,50,55,59,64,69,73,78,82] # ***Change to the bands you want to image
solar_times = ['192030'] # ***Change to the times to use for solar imaging -- these times must exist!
datstr = '20231009_' # ***Change to the date of your event
for solar_time in solar_times:
tref = Time(datstr[:4]+'-'+datstr[4:6]+'-'+datstr[6:]+' '+solar_time[:2]+':'+solar_time[2:4]+':'+solar_time[4:])
ephem = hf.read_horizons(tref, dur=1./60./24., observatory='OVRO_MMA')
if not os.path.exists('imagedir_allch'):
os.makedirs('imagedir_allch')
if not os.path.exists('fits'):
os.makedirs('fits')
outfits_helio = []
# Make all the images (by calling run_imager)
for freq in freqs:
folder = str(freq)+'MHz'
msname = folder+'/final_ms/'+datstr+solar_time+'_'+str(freq)+'MHz_final.ms'
outfits_helio += run_imager(msname, imagedir_allch='imagedir_allch/', ephem=ephem)

fitsfiles_mfs = []
fitsfiles_fch = []
for f in outfits_helio:
if 'MFS' in f:
fitsfiles_mfs.append(f)
else:
fitsfiles_fch.append(f)
## Wrap images
timestr_iso = tref.isot[:-4].replace(':','')+'Z'
fits_mfs = 'fits/ovro-lwa.lev1_mfs_10s.' + timestr_iso + '.image.fits'
fits_fch = 'fits/ovro-lwa.lev1_fch_10s.' + timestr_iso + '.image.fits'
# multi-frequency synthesis images
fitsfiles_mfs.sort()
ndfits.wrap(fitsfiles_mfs, outfitsfile=fits_mfs)

# fine channel spectral images
fitsfiles_fch.sort()
ndfits.wrap(fitsfiles_fch, outfitsfile=fits_fch)
</pre>

== What Happens When You Run the Script ==
One way to run this script is to cut-and-paste into a file, say process.py, and then in an iPython session type
<pre>
import sys
sys.path.append('/home/dgary/ovro-lwa-solar') # Change to your path where you cloned the git repository
run 'process.py'
</pre>
If all goes well, after many hours you will have all of your images. If you examine the script, you will see that there are two loops, an inner one over frequency and an outer one over time. The inner loop will create a subdirectory for the frequency it is working on (first will be subdirectory named 27MHz), then do the calibration for that frequency and create a subfolder caltables with a .bcal file in it. Luckily, this only has to be done once and then the .bcal file will be used for subsequent times so its creation will be skipped. Other files with .gcal extension will be created for the first data time, and also will be reused for subesquent times up to one hour later. When a new .gcal file is needed, the pipeline will create it automatically for you. The gain files take about 10 min for each frequency, but again is only done once for an hour of data. After the calibration is complete, <code>wsclean</code> is used to create images (in 10 subbands of each 4.5 GHz band, plus an MFS image integrated over the whole band). They are converted to heliographic coordinates and you will find them in 27MHz/images when done. This takes another 10 minutes or so.

When all of that is done for the first frequency, the whole process starts again for the next, and so one until all images for the first time are done. In this example, then, it will take about 20/min per frequency * 13 frequencies = 260 minutes (> 4 hours!) to make all 143 images for the first time (10 images per band + 1 MFS image). For subsequent times, though, the calibration step is skipped so each subsequent time will take 10 min * 13 frequencies (around 2 hours). That means the entire script will run in about 8 hours and produce 429 images.

Tohban OVRO-LWA Imaging Tutorial

2024-01-03T16:40:15Z

Dgary: /* Calibration and Imaging Script */

=Initial Setup=
The OVRO-LWA has three solar modes that can operate concurrently. These are (1) the beamformer, which creates a high-resolution spectrogram of the solar activity each day, (2) a slow visibility mode that records data in CASA ms format for all 352 antennas and all 3072 frequencies at 10-s cadence, and (3) a fast visibility mode that records data for a 48-antenna subset (generally the outer antennas) and 768 frequencies at 1-s cadence. The recorders that record the data are all activated separately, so it is not guaranteed that data from all three modes are available at any one time. Also, because of the vast data volume most of the recorded data are not saved, but rather are overwritten after a day or so, hence any data that are wanted must be explicitly saved by copying it to another location. Again because of the large volume of data, such copying is too slow to save much data (at least at present), so we can generally save only about an hour of data per day.

'''Note: This tutorial only describes how to work with the slow visibility data at the moment.'''

==Python Environment==
The imaging pipeline is written in Python 3, so in order to use it one must set up a Python 3 environment. These instructions assume you are working in your own home directory on the Pipeline machine at OVRO. First enter the bash shell if you are not already in it. Type <code>echo $0</code> to see what shell you are in. If that returns something other than -bash, type <code>bash</code> to enter the shell. Next check if you have the line <code>alias loadpyenv3.8='source /home/user/.setenv_pyenv38'</code> in your ~/.bash_aliases file. If not, add it using your favorite editor, then activate it with <code>source ~/.bash_aliases</code>. From there, you can type <code>loadpyenv3.8</code> to enter the Python 3.8 environment. Finally, from your home folder, type <code> git clone https://github.com/binchensun/ovro-lwa-solar </code> to install the OVRO-LWA code. To test your Python environment, log out and log in again fresh, then type
<pre>
$> loadpyenv3.8
$> ipython --pylab
import sys
sys.path.append('/home/dgary/ovro-lwa-solar') # Replace with your own home directory
import solar_pipeline
</pre>
If that succeeds, you should be ready to proceed.

==Where to Find Data==
The next step is to find the data you want to work with. You will need some calibration data as well as the solar data for your target date. As of this writing, the existing solar data on Pipeline, is in two separate places: /nas5/ovro-lwa-data (data up to 2023-09-03) and /nas6/ovro-lwa-data (data from 2023-09-18 and later). All of the existing beamformed data (spectrograms) are in /nas5/ovro-lwa-data/beam/beam-data.

'''This tutorial uses the example of the type II burst on 2023-07-28.'''

==Examining the Spectrogram for Your Date==
It is good practice to examine the spectrogram for your date/time, to guide your selection of frequencies and times to use for imaging. You can check the folders and subfolders in /nas5/ovro-lwa-data/beam/beam-data to see what files exist. Note that the filenames have the Modified Julian Data (mjd) followed by hours, minutes, seconds in the format <mjdday>.<hh><mm><ss>?????????? where the ? indicate more digits of the fraction of a second. The type II burst we are interested in started around 15:43 UT on 2023 July 28, which is MJD 060154, so the file we want is <code>/nas5/ovro-lwa-data/beam/beam-data/202307/beam20230728/060153_152717110834334d2be</code>, which starts at 15:27:17 UT. Generally these files contain 30 min of data. The type II continues into the next file, which is <code>060153_1558172229518804396</code>.

To read and display this file, in iPython type
[[File:20230728-type-II.png|300px|left|'''2023 July 28 Type II event spectrogram''']] <pre>
import sys # If not already loaded
sys.path.append('/nas5/ovro-lwa-data/beam/software/')
from lwa import lwa_read, lwa_plot
datadir = '/nas5/ovro-lwa-data/beam/beam-data/202307/beam20230728/'
data = lwa_read(datadir+'060153_152717110834334d2be', stokes='IV', timebin=1, freqbin=4)
lwa_plot(data, vmax=15000,vmin=10)
</pre>
which defaults to log-scaled amplitudes and viridis color table for stokes I and linear-scaled amplitudes and grayscale for stokes V, as shown at left. You can examine lwa_plot? for more options. 
 
 

==Calibration and Imaging Script==
The script below assumes some previous setup. First, a "home" directory needs to be created and the script must be run from that directory. Because of the large amount of disk space required, create your "home" directory on /data1. Mine is /data1/dgary/OVRO-LWA/20230728_workdir. Before running the script, you'll need to change the 7 lines indicated with the '''***Change''' comments.
# The first such line is the list of frequency bands you want to image. In this case I have all 13 useful bands. Frequencies below 27 MHz rarely image well and in many cases we did not save the data for those frequencies anyway.
# The second is a string representing the date of the event, including an underscore (this is part of a filename).
# The third line is a list of solar times. These times have to exactly match existing filenames, so you'll have to do a listing of the data directory to check them. ''Warning: Doing a listing of the entire data directory is time consuming and not useful, since there are many thousands of files there.'' Instead, use something like: <code>ls /nas5/ovro-lwa-data/20230728/slow/20230728_1553*</code> to limit the number of files returned.
# The fourth line is the date string of the calibration data. This will almost always be the same as the date string of the data, but it is possible to use a calibration from a different date if not too far apart.
# The fifth line is the time of the calibration data. Again, this must exist. Usually the calibration is done at night so the time will be quite different, e.g. 0500 UT, and a command like <code>ls /nas5/ovro-lwa-data/20230728/slow | head -20</code> will list the first 20 files in the folder, which are likely the calibration files. Unfortunately, no nighttime calibration exists for this date, so I had to use a daytime time, 15:40 UT.
# The sixth line is the path to the data.
# The seventh line is the path to the calibration data, again usually the same as that for the data.
<pre>
import os, glob
from ovrolwasolar import solar_pipeline, utils
from time import time

freqs=[27,32,36,41,46,50,55,59,64,69,73,78,82] # ***Change to the bands you want to image
datstr = '20230728_' # ***Change to the date of your event
solar_times = ['155306','155316','155326'] # ***Change to the times to use for solar imaging -- these times must exist!
caldatstr = '20230728_' # ***Change to the date of your cal data
cal_time = '154003' # ***Change to the time for your calibration
datapath = '/nas5/ovro-lwa-data/20230728/slow/' # ***Change to path to your data
calpath = '/nas5/ovro-lwa-data/20230728/slow/' # ***Change to path to your calibration data

home=os.getcwd()
for solar_time in solar_times:
for freq in freqs:
calib_ms=caldatstr+cal_time+'_'+str(freq)+"MHz.ms" # Will be copied from calpath
solar_ms=datstr+solar_time+'_'+str(freq)+"MHz.ms" # Will be copied from datapath
bcal='caltables/'+calib_ms.replace('ms','bcal') # Will be created if it doesn't already exist
imagename=datstr+solar_time+'_'+str(freq)+"MHz"
image_fold = 'images/'

# Create frequency folder, if it doesn't exist
freq_fold=str(freq)+"MHz"
if not os.path.isdir(freq_fold):
os.mkdir(freq_fold)

# Copy the solar data for this time (will be deleted later)
print('Copying solar data to frequency folder')
os.system("cp -r "+os.path.join(datapath,solar_ms)+"* "+freq_fold+"/")
# Copy the calibration data (will be deleted later)
print('Copying calibration data to frequency folder')
os.system("cp -r "+os.path.join(calpath,calib_ms)+"* "+freq_fold+"/")

os.chdir(freq_fold)
if not os.path.isdir(image_fold):
os.mkdir(image_fold)
if not os.path.isfile(bcal):
bcal = None
if not os.path.isdir('caltables'):
os.mkdir('caltables')
if not os.path.isdir('final_ms'):
os.mkdir('final_ms')

try:
solar_pipeline.image_ms(solar_ms=solar_ms,calib_ms=calib_ms,bcal=bcal,\
imagename=imagename,do_final_imaging=False,logfile='analysis_'+str(freq)+'.log')
msname = datstr+solar_time+'_'+str(freq)+'MHz_final.ms'
os.system("mv *calibrated_selfcalibrated_sun_only_sun_selfcalibrated_sun_only.ms final_ms/"+msname)
os.system("rm -rf *.ms* *.fits *.gcal *.cl *.badants")
# Make 10 images for this band (integrates over 19 or 20 subchannels, bandwidth ~0.4545 MHz)
os.system('wsclean -no-dirty -size 1024 1024 -scale 1arcmin -weight uniform -minuv-l 10 -name '+imagename+' -niter 10000 -mgain 0.8 -beam-fitting-size 1 -pol I -join-channels -channels-out 10 final_ms/'+msname)
# Convert images to heliocentric, move them to the final image folder, and delete all fits files
files = glob.glob('*-image.fits')
for imgfile in files:
#utils.correct_primary_beam('final_ms/'+msname, imgfile.split('-image.fits')[0])
helio_image = utils.convert_to_heliocentric_coords('final_ms/'+msname, imgfile)
os.system('mv '+helio_image+' '+image_fold)
os.system('rm *.fits')
except:
pass
os.chdir(home)

</pre>

== What Happens When You Run the Script ==
One way to run this script is to cut-and-paste into a file, say process.py, and then in an iPython session type
<pre>
import sys
sys.path.append('/home/dgary/ovro-lwa-solar') # Change to your path where you cloned the git repository
run 'process.py'
</pre>
If all goes well, after many hours you will have all of your images. If you examine the script, you will see that there are two loops, an inner one over frequency and an outer one over time. The inner loop will create a subdirectory for the frequency it is working on (first will be subdirectory named 27MHz), then do the calibration for that frequency and create a subfolder caltables with a .bcal file in it. Luckily, this only has to be done once and then the .bcal file will be used for subsequent times so its creation will be skipped. Other files with .gcal extension will be created for the first data time, and also will be reused for subesquent times up to one hour later. When a new .gcal file is needed, the pipeline will create it automatically for you. The gain files take about 10 min for each frequency, but again is only done once for an hour of data. After the calibration is complete, <code>wsclean</code> is used to create images (in 10 subbands of each 4.5 GHz band, plus an MFS image integrated over the whole band). They are converted to heliographic coordinates and you will find them in 27MHz/images when done. This takes another 10 minutes or so.

When all of that is done for the first frequency, the whole process starts again for the next, and so one until all images for the first time are done. In this example, then, it will take about 20/min per frequency * 13 frequencies = 260 minutes (> 4 hours!) to make all 143 images for the first time (10 images per band + 1 MFS image). For subsequent times, though, the calibration step is skipped so each subsequent time will take 10 min * 13 frequencies (around 2 hours). That means the entire script will run in about 8 hours and produce 429 images.

Tohban OVRO-LWA Imaging Tutorial

2024-01-02T20:58:54Z

Dgary: /* Calibration and Imaging Script */

=Initial Setup=
The OVRO-LWA has three solar modes that can operate concurrently. These are (1) the beamformer, which creates a high-resolution spectrogram of the solar activity each day, (2) a slow visibility mode that records data in CASA ms format for all 352 antennas and all 3072 frequencies at 10-s cadence, and (3) a fast visibility mode that records data for a 48-antenna subset (generally the outer antennas) and 768 frequencies at 1-s cadence. The recorders that record the data are all activated separately, so it is not guaranteed that data from all three modes are available at any one time. Also, because of the vast data volume most of the recorded data are not saved, but rather are overwritten after a day or so, hence any data that are wanted must be explicitly saved by copying it to another location. Again because of the large volume of data, such copying is too slow to save much data (at least at present), so we can generally save only about an hour of data per day.

'''Note: This tutorial only describes how to work with the slow visibility data at the moment.'''

==Python Environment==
The imaging pipeline is written in Python 3, so in order to use it one must set up a Python 3 environment. These instructions assume you are working in your own home directory on the Pipeline machine at OVRO. First enter the bash shell if you are not already in it. Type <code>echo $0</code> to see what shell you are in. If that returns something other than -bash, type <code>bash</code> to enter the shell. Next check if you have the line <code>alias loadpyenv3.8='source /home/user/.setenv_pyenv38'</code> in your ~/.bash_aliases file. If not, add it using your favorite editor, then activate it with <code>source ~/.bash_aliases</code>. From there, you can type <code>loadpyenv3.8</code> to enter the Python 3.8 environment. Finally, from your home folder, type <code> git clone https://github.com/binchensun/ovro-lwa-solar </code> to install the OVRO-LWA code. To test your Python environment, log out and log in again fresh, then type
<pre>
$> loadpyenv3.8
$> ipython --pylab
import sys
sys.path.append('/home/dgary/ovro-lwa-solar') # Replace with your own home directory
import solar_pipeline
</pre>
If that succeeds, you should be ready to proceed.

==Where to Find Data==
The next step is to find the data you want to work with. You will need some calibration data as well as the solar data for your target date. As of this writing, the existing solar data on Pipeline, is in two separate places: /nas5/ovro-lwa-data (data up to 2023-09-03) and /nas6/ovro-lwa-data (data from 2023-09-18 and later). All of the existing beamformed data (spectrograms) are in /nas5/ovro-lwa-data/beam/beam-data.

'''This tutorial uses the example of the type II burst on 2023-07-28.'''

==Examining the Spectrogram for Your Date==
It is good practice to examine the spectrogram for your date/time, to guide your selection of frequencies and times to use for imaging. You can check the folders and subfolders in /nas5/ovro-lwa-data/beam/beam-data to see what files exist. Note that the filenames have the Modified Julian Data (mjd) followed by hours, minutes, seconds in the format <mjdday>.<hh><mm><ss>?????????? where the ? indicate more digits of the fraction of a second. The type II burst we are interested in started around 15:43 UT on 2023 July 28, which is MJD 060154, so the file we want is <code>/nas5/ovro-lwa-data/beam/beam-data/202307/beam20230728/060153_152717110834334d2be</code>, which starts at 15:27:17 UT. Generally these files contain 30 min of data. The type II continues into the next file, which is <code>060153_1558172229518804396</code>.

To read and display this file, in iPython type
[[File:20230728-type-II.png|300px|left|'''2023 July 28 Type II event spectrogram''']] <pre>
import sys # If not already loaded
sys.path.append('/nas5/ovro-lwa-data/beam/software/')
from lwa import lwa_read, lwa_plot
datadir = '/nas5/ovro-lwa-data/beam/beam-data/202307/beam20230728/'
data = lwa_read(datadir+'060153_152717110834334d2be', stokes='IV', timebin=1, freqbin=4)
lwa_plot(data, vmax=15000,vmin=10)
</pre>
which defaults to log-scaled amplitudes and viridis color table for stokes I and linear-scaled amplitudes and grayscale for stokes V, as shown at left. You can examine lwa_plot? for more options. 
 
 

==Calibration and Imaging Script==
The script below assumes some previous setup. First, a "home" directory needs to be created and the script must be run from that directory. Because of the large amount of disk space required, create your "home" directory on /data1. Mine is /data1/dgary/OVRO-LWA/20230728_workdir. Before running the script, you'll need to change the 7 lines indicated with the '''***Change''' comments.
# The first such line is the list of frequency bands you want to image. In this case I have all 13 useful bands. Frequencies below 27 MHz rarely image well and in many cases we did not save the data for those frequencies anyway.
# The second is a string representing the date of the event, including an underscore (this is part of a filename).
# The third line is a list of solar times. These times have to exactly match existing filenames, so you'll have to do a listing of the data directory to check them. ''Warning: Doing a listing of the entire data directory is time consuming and not useful, since there are many thousands of files there.'' Instead, use something like: <code>ls /nas5/ovro-lwa-data/20230728/slow/20230728_1553*</code> to limit the number of files returned.
# The fourth line is the date string of the calibration data. This will almost always be the same as the date string of the data, but it is possible to use a calibration from a different date if not too far apart.
# The fifth line is the time of the calibration data. Again, this must exist. Usually the calibration is done at night so the time will be quite different, e.g. 0500 UT, and a command like <code>ls /nas5/ovro-lwa-data/20230728/slow | head -20</code> will list the first 20 files in the folder, which are likely the calibration files. Unfortunately, no nighttime calibration exists for this date, so I had to use a daytime time, 15:40 UT.
# The sixth line is the path to the data.
# The seventh line is the path to the calibration data, again usually the same as that for the data.
<pre>
import os, glob
import utils
from time import time
import solar_pipeline

freqs=[27,32,36,41,46,50,55,59,64,69,73,78,82] # ***Change to the bands you want to image
datstr = '20230728_' # ***Change to the date of your event
solar_times = ['155306','155316','155326'] # ***Change to the times to use for solar imaging -- these times must exist!
caldatstr = '20230728_' # ***Change to the date of your cal data
cal_time = '154003' # ***Change to the time for your calibration
datapath = '/nas5/ovro-lwa-data/20230728/slow/' # ***Change to path to your data
calpath = '/nas5/ovro-lwa-data/20230728/slow/' # ***Change to path to your calibration data

home=os.getcwd()
for solar_time in solar_times:
for freq in freqs:
calib_ms=caldatstr+cal_time+'_'+str(freq)+"MHz.ms" # Will be copied from calpath
solar_ms=datstr+solar_time+'_'+str(freq)+"MHz.ms" # Will be copied from datapath
bcal='caltables/'+calib_ms.replace('ms','bcal') # Will be created if it doesn't already exist
imagename=datstr+solar_time+'_'+str(freq)+"MHz"
image_fold = 'images/'

# Create frequency folder, if it doesn't exist
freq_fold=str(freq)+"MHz"
if not os.path.isdir(freq_fold):
os.mkdir(freq_fold)

# Copy the solar data for this time (will be deleted later)
print('Copying solar data to frequency folder')
os.system("cp -r "+os.path.join(datapath,solar_ms)+"* "+freq_fold+"/")
# Copy the calibration data (will be deleted later)
print('Copying calibration data to frequency folder')
os.system("cp -r "+os.path.join(calpath,calib_ms)+"* "+freq_fold+"/")

os.chdir(freq_fold)
if not os.path.isdir(image_fold):
os.mkdir(image_fold)
if not os.path.isfile(bcal):
bcal = None
if not os.path.isdir('caltables'):
os.mkdir('caltables')
if not os.path.isdir('final_ms'):
os.mkdir('final_ms')

try:
solar_pipeline.image_ms(solar_ms=solar_ms,calib_ms=calib_ms,bcal=bcal,\
imagename=imagename,do_final_imaging=False,logfile='analysis_'+str(freq)+'.log')
msname = datstr+solar_time+'_'+str(freq)+'MHz_final.ms'
os.system("mv *calibrated_selfcalibrated_sun_only_sun_selfcalibrated_sun_only.ms final_ms/"+msname)
os.system("rm -rf *.ms* *.fits *.gcal *.cl *.badants")
# Make 10 images for this band (integrates over 19 or 20 subchannels, bandwidth ~0.4545 MHz)
os.system('wsclean -no-dirty -size 1024 1024 -scale 1arcmin -weight uniform -minuv-l 10 -name '+imagename+' -niter 10000 -mgain 0.8 -beam-fitting-size 1 -pol I -join-channels -channels-out 10 final_ms/'+msname)
# Convert images to heliocentric, move them to the final image folder, and delete all fits files
files = glob.glob('*-image.fits')
for imgfile in files:
#utils.correct_primary_beam('final_ms/'+msname, imgfile.split('-image.fits')[0])
helio_image = utils.convert_to_heliocentric_coords('final_ms/'+msname, imgfile)
os.system('mv '+helio_image+' '+image_fold)
os.system('rm *.fits')
except:
pass
os.chdir(home)

</pre>

== What Happens When You Run the Script ==
One way to run this script is to cut-and-paste into a file, say process.py, and then in an iPython session type
<pre>
import sys
sys.path.append('/home/dgary/ovro-lwa-solar') # Change to your path where you cloned the git repository
run 'process.py'
</pre>
If all goes well, after many hours you will have all of your images. If you examine the script, you will see that there are two loops, an inner one over frequency and an outer one over time. The inner loop will create a subdirectory for the frequency it is working on (first will be subdirectory named 27MHz), then do the calibration for that frequency and create a subfolder caltables with a .bcal file in it. Luckily, this only has to be done once and then the .bcal file will be used for subsequent times so its creation will be skipped. Other files with .gcal extension will be created for the first data time, and also will be reused for subesquent times up to one hour later. When a new .gcal file is needed, the pipeline will create it automatically for you. The gain files take about 10 min for each frequency, but again is only done once for an hour of data. After the calibration is complete, <code>wsclean</code> is used to create images (in 10 subbands of each 4.5 GHz band, plus an MFS image integrated over the whole band). They are converted to heliographic coordinates and you will find them in 27MHz/images when done. This takes another 10 minutes or so.

When all of that is done for the first frequency, the whole process starts again for the next, and so one until all images for the first time are done. In this example, then, it will take about 20/min per frequency * 13 frequencies = 260 minutes (> 4 hours!) to make all 143 images for the first time (10 images per band + 1 MFS image). For subsequent times, though, the calibration step is skipped so each subsequent time will take 10 min * 13 frequencies (around 2 hours). That means the entire script will run in about 8 hours and produce 429 images.

Tohban OVRO-LWA Imaging Tutorial

2024-01-02T18:38:50Z

Dgary: /* Calibration and Imaging Script */

=Initial Setup=
The OVRO-LWA has three solar modes that can operate concurrently. These are (1) the beamformer, which creates a high-resolution spectrogram of the solar activity each day, (2) a slow visibility mode that records data in CASA ms format for all 352 antennas and all 3072 frequencies at 10-s cadence, and (3) a fast visibility mode that records data for a 48-antenna subset (generally the outer antennas) and 768 frequencies at 1-s cadence. The recorders that record the data are all activated separately, so it is not guaranteed that data from all three modes are available at any one time. Also, because of the vast data volume most of the recorded data are not saved, but rather are overwritten after a day or so, hence any data that are wanted must be explicitly saved by copying it to another location. Again because of the large volume of data, such copying is too slow to save much data (at least at present), so we can generally save only about an hour of data per day.

'''Note: This tutorial only describes how to work with the slow visibility data at the moment.'''

==Python Environment==
The imaging pipeline is written in Python 3, so in order to use it one must set up a Python 3 environment. These instructions assume you are working in your own home directory on the Pipeline machine at OVRO. First enter the bash shell if you are not already in it. Type <code>echo $0</code> to see what shell you are in. If that returns something other than -bash, type <code>bash</code> to enter the shell. Next check if you have the line <code>alias loadpyenv3.8='source /home/user/.setenv_pyenv38'</code> in your ~/.bash_aliases file. If not, add it using your favorite editor, then activate it with <code>source ~/.bash_aliases</code>. From there, you can type <code>loadpyenv3.8</code> to enter the Python 3.8 environment. Finally, from your home folder, type <code> git clone https://github.com/binchensun/ovro-lwa-solar </code> to install the OVRO-LWA code. To test your Python environment, log out and log in again fresh, then type
<pre>
$> loadpyenv3.8
$> ipython --pylab
import sys
sys.path.append('/home/dgary/ovro-lwa-solar') # Replace with your own home directory
import solar_pipeline
</pre>
If that succeeds, you should be ready to proceed.

==Where to Find Data==
The next step is to find the data you want to work with. You will need some calibration data as well as the solar data for your target date. As of this writing, the existing solar data on Pipeline, is in two separate places: /nas5/ovro-lwa-data (data up to 2023-09-03) and /nas6/ovro-lwa-data (data from 2023-09-18 and later). All of the existing beamformed data (spectrograms) are in /nas5/ovro-lwa-data/beam/beam-data.

'''This tutorial uses the example of the type II burst on 2023-07-28.'''

==Examining the Spectrogram for Your Date==
It is good practice to examine the spectrogram for your date/time, to guide your selection of frequencies and times to use for imaging. You can check the folders and subfolders in /nas5/ovro-lwa-data/beam/beam-data to see what files exist. Note that the filenames have the Modified Julian Data (mjd) followed by hours, minutes, seconds in the format <mjdday>.<hh><mm><ss>?????????? where the ? indicate more digits of the fraction of a second. The type II burst we are interested in started around 15:43 UT on 2023 July 28, which is MJD 060154, so the file we want is <code>/nas5/ovro-lwa-data/beam/beam-data/202307/beam20230728/060153_152717110834334d2be</code>, which starts at 15:27:17 UT. Generally these files contain 30 min of data. The type II continues into the next file, which is <code>060153_1558172229518804396</code>.

To read and display this file, in iPython type
[[File:20230728-type-II.png|300px|left|'''2023 July 28 Type II event spectrogram''']] <pre>
import sys # If not already loaded
sys.path.append('/nas5/ovro-lwa-data/beam/software/')
from lwa import lwa_read, lwa_plot
datadir = '/nas5/ovro-lwa-data/beam/beam-data/202307/beam20230728/'
data = lwa_read(datadir+'060153_152717110834334d2be', stokes='IV', timebin=1, freqbin=4)
lwa_plot(data, vmax=15000,vmin=10)
</pre>
which defaults to log-scaled amplitudes and viridis color table for stokes I and linear-scaled amplitudes and grayscale for stokes V, as shown at left. You can examine lwa_plot? for more options. 
 
 

==Calibration and Imaging Script==
The script below assumes some previous setup. First, a "home" directory needs to be created and the script must be run from that directory. Because of the large amount of disk space required, create your "home" directory on /data1. Mine is /data1/dgary/OVRO-LWA/20230728_workdir. Before running the script, you'll need to change the 7 lines indicated with the '''***Change''' comments.
# The first such line is the list of frequency bands you want to image. In this case I have all 13 useful bands. Frequencies below 27 MHz rarely image well and in many cases we did not save the data for those frequencies anyway.
# The second is a string representing the date of the event, including an underscore (this is part of a filename).
# The third line is a list of solar times. These times have to exactly match existing filenames, so you'll have to do a listing of the data directory to check them. ''Warning: Doing a listing of the entire data directory is time consuming and not useful, since there are many thousands of files there.'' Instead, use something like: <code>ls /nas5/ovro-lwa-data/20230728/slow/20230728_1553*</code> to limit the number of files returned.
# The fourth line is the date string of the calibration data. This will almost always be the same as the date string of the data, but it is possible to use a calibration from a different date if not too far apart.
# The fifth line is the time of the calibration data. Again, this must exist. Usually the calibration is done at night so the time will be quite different, e.g. 0500 UT, and a command like <code>ls /nas5/ovro-lwa-data/20230728/slow | head -20</code> will list the first 20 files in the folder, which are likely the calibration files. Unfortunately, no nighttime calibration exists for this date, so I had to use a daytime time, 15:40 UT.
# The sixth line is the path to the data.
# The seventh line is the path to the calibration data, again usually the same as that for the data.
<pre>
import os, glob
import utils
from time import time
import solar_pipeline

freqs=[27,32,36,41,46,50,55,59,64,69,73,78,82] # ***Change to the bands you want to image
datstr = '20230728_' # ***Change to the date of your event
solar_times = ['155306','155316','155326'] # ***Change to the times to use for solar imaging -- these times must exist!
caldatstr = '20230728_' # ***Change to the date of your cal data
cal_time = '154003' # ***Change to the time for your calibration
datapath = '/nas5/ovro-lwa-data/20230728/slow/' # ***Change to path to your data
calpath = '/nas5/ovro-lwa-data/20230728/slow/' # ***Change to path to your calibration data

home=os.getcwd()
for solar_time in solar_times:
for freq in freqs:
calib_ms=caldatstr+cal_time+'_'+str(freq)+"MHz.ms" # Will be copied from calpath
solar_ms=datstr+solar_time+'_'+str(freq)+"MHz.ms" # Will be copied from datapath
bcal='caltables/'+calib_ms.replace('ms','bcal') # Will be created if it doesn't already exist
imagename=datstr+solar_time+'_'+str(freq)+"MHz"
image_fold = 'images/'

# Create frequency folder, if it doesn't exist
freq_fold=str(freq)+"MHz"
if not os.path.isdir(freq_fold):
os.mkdir(freq_fold)

# Copy the solar data for this time (will be deleted later)
print('Copying solar data to frequency folder')
os.system("cp -r "+os.path.join(datapath,solar_ms)+"* "+freq_fold+"/")
# Copy the calibration data (will be deleted later)
print('Copying calibration data to frequency folder')
os.system("cp -r "+os.path.join(calpath,calib_ms)+"* "+freq_fold+"/")

os.chdir(freq_fold)
if not os.path.isdir(image_fold):
os.mkdir(image_fold)
if not os.path.isfile(bcal):
bcal = None
if not os.path.isdir('caltables'):
os.mkdir('caltables')
if not os.path.isdir('final_ms'):
os.mkdir('final_ms')

try:
solar_pipeline.image_ms(solar_ms=solar_ms,calib_ms=calib_ms,bcal=bcal,\
imagename=imagename,do_final_imaging=False,logfile='analysis_'+str(freq)+'.log')
msname = datstr+solar_time+'_'+str(freq)+'MHz_final.ms'
os.system("mv *calibrated_selfcalibrated_sun_only_sun_selfcalibrated_sun_only.ms final_ms/"+msname)
os.system("rm -rf *.ms* *.fits *.gcal *.cl *.badants")
# Make 10 images for this band (integrates over 19 or 20 subchannels, bandwidth ~0.4545 MHz)
os.system('wsclean -no-dirty -size 1024 1024 -scale 1arcmin -weight uniform -minuv-l 10 -name '+imagename+' -niter 10000 -mgain 0.8 -beam-fitting-size 1 -pol I -join-channels -channels-out 10 final_ms/'+msname)
# Convert images to heliocentric, move them to the final image folder, and delete all fits files
files = glob.glob('*-image.fits')
for imgfile in files:
utils.correct_primary_beam('final_ms/'+msname, imgfile.split('-image.fits')[0])
helio_image = utils.convert_to_heliocentric_coords('final_ms/'+msname, imgfile)
os.system('mv '+helio_image+' '+image_fold)
os.system('rm *.fits')
except:
pass
os.chdir(home)

</pre>

== What Happens When You Run the Script ==
One way to run this script is to cut-and-paste into a file, say process.py, and then in an iPython session type
<pre>
import sys
sys.path.append('/home/dgary/ovro-lwa-solar') # Change to your path where you cloned the git repository
run 'process.py'
</pre>
If all goes well, after many hours you will have all of your images. If you examine the script, you will see that there are two loops, an inner one over frequency and an outer one over time. The inner loop will create a subdirectory for the frequency it is working on (first will be subdirectory named 27MHz), then do the calibration for that frequency and create a subfolder caltables with a .bcal file in it. Luckily, this only has to be done once and then the .bcal file will be used for subsequent times so its creation will be skipped. Other files with .gcal extension will be created for the first data time, and also will be reused for subesquent times up to one hour later. When a new .gcal file is needed, the pipeline will create it automatically for you. The gain files take about 10 min for each frequency, but again is only done once for an hour of data. After the calibration is complete, <code>wsclean</code> is used to create images (in 10 subbands of each 4.5 GHz band, plus an MFS image integrated over the whole band). They are converted to heliographic coordinates and you will find them in 27MHz/images when done. This takes another 10 minutes or so.

When all of that is done for the first frequency, the whole process starts again for the next, and so one until all images for the first time are done. In this example, then, it will take about 20/min per frequency * 13 frequencies = 260 minutes (> 4 hours!) to make all 143 images for the first time (10 images per band + 1 MFS image). For subsequent times, though, the calibration step is skipped so each subsequent time will take 10 min * 13 frequencies (around 2 hours). That means the entire script will run in about 8 hours and produce 429 images.

2.1-m Antennas

2023-12-05T22:57:57Z

Dgary: /* More Focus Tests (2023-Dec-04) */

=Az-El Mount 2.1 m Dishes=

==Testing RF Spin Feed==
On 2023 Mar 12 we are testing a new feed using antenna 3. This feed is manufactured by RF Spin, and is a Quad-Ridge Flared-Horn (QRFH) feed. This dual-polarization feed is rated for 1-18 GHz, but the beam gets quite narrow at higher frequencies, so we can expect under-illumination at the higher frequencies.

===Pointing/Focus Procedure===
Today is the first test of the feed on an antenna, so our procedure will be to first mount the feed (orientation is 90-degrees uncertain, but that can be determined by cross-correlation with other dishes), then do a SOLPNTCAL to check pointing, update the pointing (possibly for several iterations), then attempt to adjust focus. At the end of that procedure, we should have a good idea of the pointing performance vs. frequency. I am hoping to find that the pointing (primary beam) is very stable and uniform over frequency.

The feed has been mounted and both a GAINCAL and SOLPNTCAL have been done. It seems we also need a SKYCAL although I thought the code would allow that to be missing. I'll try to fix this later, but for now I also ran a SKYCAL. The calibration now completes.

[[File:Explanation_Fig.png|thumb|400px|Explanation for apparently strange measurements. (a) When near the meridian, and RA/Dec sweep is aligned 45 degrees from the E-plane of the feeds so both sweeps and both feeds give similar beam sizes. (b) When well past the meridian, the RA/Dec axes are tilted relative to the AzEl-mounted feeds, so the RA sweep gives a narrow X beam and a wide Y beam while the Dec sweep gives the opposite behavior.]]

'''1.''' The result of the first observation, filename IDB20230312165723, is that the beamwidth is very broad, around twice the nominal primary beamwidth. This might be due to being way out of focus, or it may be the under-illumination. We have now moved the feed about 1" (2.5 cm) farther from the dish.
<gallery mode="nolines">
File:RFSpin_test1_X_165724.png|thumb|100px|Test 1 X_polarization beam size for ants 1-4.
File:RFSpin_test1_Y_165724.png|thumb|100px|Test 1 Y_polarization beam size for ants 1-4.
File:RFSpin_test1_Xoffset_165724.png|thumb|400px|Test 1 X_polarization pointing offset for ant 3.
File:RFSpin_test1_Yoffset_165724.png|thumb|400px|Test 1 Y_polarization pointing offset for ant 3.
File:RFSpin_test1_XYcalfac_165724.png|thumb|100px|Test 1 Cal factor plot for ants 1-4.
</gallery>

'''2.''' The result of the second observation, filename IDB20230312200219, is that the beamwidth is much closer to nominal (!), but strangely the pointing behavior is different for the X feed than for the Y feed. But I'll try moving the feed another 0.5" (1.25 cm) farther and see what happens.
<gallery mode="nolines">
File:RFSpin_test2_X_200220.png|thumb|100px|Test 2 X_polarization beam size for ants 1-4.
File:RFSpin_test2_Y_200220.png|thumb|100px|Test 2 Y_polarization beam size for ants 1-4.
File:RFSpin_test2_Xoffset_200220.png|thumb|400px|Test 2 X_polarization pointing offset for ant 3.
File:RFSpin_test2_Yoffset_200220.png|thumb|400px|Test 2 Y_polarization pointing offset for ant 3.
File:RFSpin_test2_XYcalfac_200220.png|thumb|100px|Test 2 Cal factor plot for ants 1-4.
</gallery>

'''3.''' The result of the third observation, filename IDB20230312205319, is that the beamwidth in one axis is broad again, so things seem to have gotten worse relative to the second observation. I am going to try to split the difference between the first two, i.e. move the feed 0.75" toward the dish relative to its current position.
<gallery mode="nolines">
File:RFSpin_test3_X_205320.png|thumb|100px|Test 3 X_polarization beam size for ants 1-4.
File:RFSpin_test3_Y_205320.png|thumb|100px|Test 3 Y_polarization beam size for ants 1-4.
File:RFSpin_test3_Xoffset_205320.png|thumb|400px|Test 3 X_polarization pointing offset for ant 3.
File:RFSpin_test3_Yoffset_205320.png|thumb|400px|Test 3 Y_polarization pointing offset for ant 3.
File:RFSpin_test3_XYcalfac_205320.png|thumb|100px|Test 3 Cal factor plot for ants 1-4.
</gallery>

'''4.''' The result of the fourth observation, filename IDB20230312213919, is worse in beamwidth on some axes, so I will go back away from the dish again. I got a bit lost in positioning the feed. I think it will be a bit farther out from the dish than the 1" position, so intermediate between 1" and 1.5".
<gallery mode="nolines">
File:RFSpin_test4_X_213920.png|thumb|100px|Test 4 X_polarization beam size for ants 1-4.
File:RFSpin_test4_Y_213920.png|thumb|100px|Test 4 Y_polarization beam size for ants 1-4.
File:RFSpin_test4_Xoffset_213920.png|thumb|400px|Test 4 X_polarization pointing offset for ant 3.
File:RFSpin_test4_Yoffset_213920.png|thumb|400px|Test 4 Y_polarization pointing offset for ant 3.
File:RFSpin_test4_XYcalfac_213920.png|thumb|100px|Test 4 Cal factor plot for ants 1-4.
</gallery>

'''5.''' The result of the fifth observation, filename IDB20230312222119, is still a large beamwidth on some axes. It is not clear to me what might be the cause of this. The gaussian fits look good, but the widths are clearly varying a lot on X feed RA and Y feed Dec. The sizes for the other axes are much narrower and very steady.
<gallery mode="nolines">
File:RFSpin_test5_X_222120.png|thumb|100px|Test 5 X_polarization beam size for ants 1-4.
File:RFSpin_test5_Y_222120.png|thumb|100px|Test 5 Y_polarization beam size for ants 1-4.
File:RFSpin_test5_Xoffset_222120.png|thumb|400px|Test 5 X_polarization pointing offset for ant 3.
File:RFSpin_test5_Yoffset_222120.png|thumb|400px|Test 5 Y_polarization pointing offset for ant 3.
File:RFSpin_test5_XYcalfac_222120.png|thumb|100px|Test 5 Cal factor plot for ants 1-4.
</gallery>

===2023 Mar 13 Focus Tests===
We have figured out that the weirdness of the previous tests was that we were doing an RA-Dec cross pattern but the feeds are moving on an AzEl mount, so their orientation was changing for each test relative to the search pattern. This is coupled with a VERY different beam size in the parallel and cross orientations, so the axis that was affected most kept moving. I have arranged to do the cross pattern in AzEl, and now we are consistently getting the same beam size for both feeds, and it should not change with time. So I am hopeful that a new focus search will give more consistent and comparable results.

We are doing a new series of tests where the focus distance will start at the position farthest from the dish and move in (toward the dish, so farther out on the studs) 1 cm at a time. Rather than doing the analysis between tests, which is quite time consuming, we will just do all of the tests at once, one after another, and I'll do the analysis afterwards.

[[File:RFSpin_bsize_20230313.png|800px|left|'''Beamsize Test Results:''' ''top:'' X beamsize in Az direction vs. focus distance. ''row 2:'' X beamsize in El direction. ''row 3:'' Y beamsize in Az direction. ''bottom:'' Y beamsize in El direction. The nominal beam size for a 2.1-m dish is the orange curve in each plot. Note the search bounds are set not to exceed twice nominal).]]

[[File:RFSpin_offsets_20230313.png|800px|left|'''Pointing Offset Test Results:''' ''top:'' X offsets in Az direction vs. focus distance. ''row 2:'' X offsets in El direction. ''row 3:'' Y offsets in Az direction. ''bottom:'' Y offsets in El direction. The solar disk size is +/- 0.25 degree.]]

Test 1: 20:24:57 77 cm from dish

Test 2: 20:40:59 76 cm from dish

Test 3: 20:59:13 75 cm from dish

Test 4: 21:10:11 74 cm from dish

Test 5: 21:21:16 73 cm from dish

Test 6: 21:33:01 72 cm from dish

Test 7: 21:44:31 71 cm from dish

Test 8: 21:56:25 70 cm from dish

Test 9: 22:07:11 69 cm from dish

Test 10: 22:18:21 68 cm from dish

Test 11: 22:30:39 67 cm from dish

Test 12: 22:43:11 66 cm from dish

Test 13: 23:04:55 65 cm from dish

Test 14: 23:18:16 64 cm from dish

'''Results:''' The results are shown in the two figures above and are quite regular and understandable. The best focus is clearly around 69 cm from the dish, with the beamsize being larger than nominal in both axes. However, the earlier tests clearly show that the E-plane feed beamwidth is larger on the dish (illuminates more of the dish), and hence smaller on the sky, so the beamsize in that direction is more or less nominal. The B-plane feed beamwidth is smaller on the dish (illuminates only the central part of the dish), and hence nearly twice as large as the nominal size on the sky.

===Phase Calibration===
Once the best pointing and focus have been found, we will observe a calibrator and check the delays. I tried this on 2023 Mar 12 when the focus was not correctly set, in the file IDB20230312224929. This resulted in an "okay" delay without modification, which is interesting. However, when I plotted the Ant 14 - Ant 3 phase it was not flat with frequency, but showed the characteristic U shape indicating a change in feed phase center vs. frequency. The U was much less pronounced than that of the Tecom feeds relative to the 27-m feed horns, so presumably the feed phase center has less of a meander than the Tecom feeds. This exercise needs to be repeated, but is postponed until tomorrow (2023 Mar 15) due to rain today.

===2023 Jul 22 Tests of Feed with Radome===
On 21 July, Owen got our new radome-equipped feed mounted on Ant 11, so I spent 21 and 22 July working on pointing and delays. The feed seems to be performing nominally, with the expected oval-shaped beam that is twice as wide in the B plane (because the feed pattern is twice as narrow, which under-illuminates the dish). Since Ant 11 is an equatorial mount, it is not necessary to use the Az-El sweep pattern to measure the beam size. Below are the results after adjusting the pointing. Note that this measurement indicates that the feed is rotated 45 degrees from what it should be, showing the maximally different beam sizes for orthogonal directions of a + pattern instead of the roughly equal responses expected of an X pattern.
<gallery mode="nolines">
File:20230722-Xfeed-beamsize.png | thumb | 400px |
File:20230722-Yfeed-beamsize.png | thumb | 400px |
</gallery>

==Pointing in the Era of RF Spin Feeds==
We have purchased 13 RF Spin feeds equipped with radome. These feeds are to replace the many burnt feeds, and we will fit out the entire array with them. However, their elongated feed pattern is causing problems with determining optimum pointing using our current scheme, and so they require a new method of pointing calibration. The problem stems from the fact that the feed pattern center (x direction, say) shifts as the other (y coordinate) changes, so determining a center from a simple RA-Dec cross pattern doesn't work. As a check, I performed a grid of off-point measurements that demonstrates the highly elliptical feed pattern as shown below for the feed on Ant 11.
<gallery mode="nolines">
File:20231013-Xfeed-beampattern.png | thumb | 400px |
File:20231013-Yfeed-beampattern.png | thumb | 400px |
</gallery>

A better way to do the search is to rotate the cross pattern to align with the feed axes (which are in an X shape relative to their coordinate axes) as shown in the figure at right.
[[File:Explanation_Fig2.png|thumb|150px|New Pointing Search Pattern. Sweeping in this way means that the center of the pattern in one dimension remains in the same place as the offset in the other dimension changes. This will also provide a stable measurement of the beam widths in the two orthogonal directions for each polarization.]]
The problem is that this alignment needs to be done with offsets in RA-Dec for the equatorial dishes and in Az-El for the AzEl dishes. Also, the analysis of the data becomes a bit more complicated. But since this is obviously the right thing to do, I will proceed with the idea. Taking the data will be easy enough using the already established means of creating offsets in a trajectory file, sending it to the Az-El dishes via a file with a .azel extension, and to the equatorial dishes via a file with a .radec extension. However, the Az coordinates should be increased by Az/cos(El), and the RA coordinates should be increased by RA/cos(Dec), so these would have to be calculated for the date/time in question. That means writing a routine to create the files on the fly. The analysis is not that different from what I do now, but with a few important changes such as calculating the vector offset length and keeping track of the fact that RA and Az offsets have opposite signs!

==More Focus Tests (2023-Dec-05)==
antenna focus posn start time
ANT 4 11.5 cm 18:15 UT
ANT 4 8.5 cm 20:26 UT
ANT 4 9.5 cm 20:38 UT
ANT 4 10.5 cm 20:50 UT
ANT 4 12.5 cm 21:03 UT
ANT 4 13.5 cm 21:18 UT
ANT 4 14.5 cm 21:34 UT

=Equatorial Mount 2.1 m Dishes=
EOVSA comprises 8 newer azimuth-elevation-mounted 2.1 m dishes (plus currently a 9th one, the South Pole dish), and 5 older equatorial-mounted 2.1 m dishes. This document describes some of the important differences for these older dishes.
===Parallactic angle===
The equatorial mounts were outfitted with the same reflector as used for the newer dishes, so that they function in the same way, except that their feeds are fixed in orientation on the sky while the feeds on the newer azel dishes rotate due to the parallactic angle. This angle is computed by the schedule (in stateframe.py), for the current pointing coordinates of each antenna, and inserted into the stateframe as Sche_Data_Chi (SQL naming convention), or sf[‘Schedule’][‘Data’][‘Chi’] (python naming convention), defined as the angle of the azel dish feed relative to an equatorial mount. It should be noted that it is calculated for all antennas, independent of whether the dish is an azel or equatorial mount. For a given azimuth and elevation, the paralactic angle is computed from
<center><math>\chi=\arctan 2(-\cos\lambda \sin a , \sin\lambda \cos e- \cos \lambda \sin e\cos a ) </math></center>

where <math> \lambda</math> = latitude (37.233170 degrees for OVRO), <math>a</math> = azimuth, and <math>e</math> = elevation. The arctan2 function resolves the 180-degree ambiguity. Note that any baseline involving two dissimilar dishes, the phase will rotate according to the parallactic angle, and will need to be corrected by the DPP prior to writing to the Miriad database. The default phase will be that of the azel dishes—that is, baselines with one azel and one equatorial dish will be phase-corrected to correspond to the phase as measured by two azel dishes. [This statement will need to be tested, and possibly amended if it is not correct.]

===Pointing of the equatorial-mount dishes—step size===
The equatorially-mounted dishes have a step-motor drive system, consisting of a motor of ''s'' = 200 steps/revolution, followed by a harmonic drive (a complication is that we have two DIFFERENT harmonic ratios in use, three dishes with ''h'' = 100:1 and two with ''h'' = 160:1). These motors drive a 20-tooth sprocket gear and meshes with a chain having the equivalent of 225 “teeth” in one revolution, for a further reduction ''r'' = 225:20. In addition, we are running the motors with a 16:1 microstepping ratio (<math>\mu</math>), which means that 16 microsteps are needed for one motor step. It is these microsteps that are counted by the system. The resulting of microsteps/degree, then, is
<center><math>n=\mu shr/360 </math></center>
This makes a nice round number, ''n'' = 10000 steps/degree for ''h'' = 100:1, and ''n'' = 16000 steps/degree for ''h'' = 160:1. Currently, Ants 9, 11 and 13 have 10000 steps/degree, while Ants 10, and ultimately 12 will have 16000 steps/degree. These values are given in the crio.ini file.
Obviously, these are nominal values, and the true step size could be slightly different. The step size needs to be part of the pointing parameter solution.

===Pointing of the equatorial-mount dishes—restricted sky coverage===
The equatorial-mount dishes have a restricted sky coverage relative to the azel dishes, given in terms of hour angle limits and declication limits. The precise limits (prior to any pointing corrections) can be determined by adjusting the “hard limits” (limit switches) to trigger just before the antenna hits the stops, and reading the angles at those stopped points. In order to achieve the greatest sky coverage, the hard limits should be set as close as possible to the stops, but with due regard for possible collisions of cables and other obstructions by the mount. In particular, the thick conduit on the north side of the mounts can interfere with the counter-weights when close to the stops, so the limit switches must be set somewhat away from the stops to allow the counter-weights to clear. This has been done with some care on antennas 9 and 10, with the following results (by way of example). The “soft limits” are then selected to stop the motion programmatically just before the limit switch would trigger. It is very important that the motors never reach the hard stops, since that causes the motor to stall while still counting, and hence the step count is compromised. The pointing is only good if the step count is known.
{| class="wikitable"
!Axis
!Ant 9 Hard Limit
!Ant 9 Soft Limit
!Ant 10 Hard Limit
!Ant 10 Soft Limit
|-
| HA Low
| -59.81
| -59.5
| -58.7
| -58.0
|-
| HA High
| +58.33
| +58.0
| +59.3
| +59.0
|-
| Dec Low
| -24.28
| -24.0
| -24.27
| -24.0
|-
| Dec Hi
| +45.43
| +45.0
| +46.25
| +46.0
|-
|}

One concern is that, once the pointing coefficients (and step size) are determined, the angular positions shift somewhat. It would be better to have these hard- and soft-limits not change just because of pointing coefficient adjustments. This will require some thought.
One consequence of this restricted sky coverage is that there will be times (especially in the summer) when some of the dishes cannot reach the Sun or calibrator. With the current set up, when a position is requested that cannot be reached by a dish, it will go as close to the position as possible and then just wait there. The position error can be used to determine which dishes are not tracking. For calibration, all calibrator sources will need to be chosen to respect the equatorial dishes, however, since the 27-m antennas also have this same sky coverage limitation. Therefore, the schedule, which chooses the “best” calibrator automatically, must be set to use the above sky coverage limitation.
Another, rather serious consequence of the restricted sky coverage is that the SOLPNTCAL procedure, which currently runs twice per day, works by off-pointing the dishes by +/- 5 degrees from the Sun in both RA and Dec. Since the south limit of the dishes is only -24 degrees, the dishes will not be able to reach -5 degrees from Sun center whenever the Sun is below declination -19 degrees. This is a date range of roughly Nov 18-Jan 25! During this period, the equatorial-mount dishes will not be able to do a SOLPNTCAL. It could be possible to somehow adjust the procedure to allow some sort of analysis (full HA and half of Dec, for example).

===Pointing of the equatorial-mount dishes—star pointing===
I made an attempt to observe stars with Ant 9, but was not happy with the constant vibrations, which cause the stars to be linear rather than round. I discussed it with Kjell, and he had a new mount for the telescope made (Figure 1), which will go in place of the feed package. With luck, this should allow for much less vibrational motion and hence result in much better star images. I plan to do a first test on Ant 9 tonight.
[[File: new_ telescope_mount.png|thumb|600px|Figure 1: The new mount for the optical telescope, to be put in place of the radio front-end receiver. This should greatly reduce vibrations that lead to non-circular stars.]]

In addition, I updated the startracktable() routine in readbsc.py to account for the reduced sky coverage of the equatorial-mount dishes, since my earlier attempt did not do this, and the antenna spent a lot of time at the limits.

= Debugging =
Ant 12 (the SPASRT antenna) may need its turn count adjusted. To do this, connect to its web page and change parameter 20.16. If its current turn count is 2, set it to 1 and reboot. If it is currently 1, set it to 2 and reboot.

2.1-m Antennas

2023-12-04T22:51:41Z

Dgary: /* Pointing in the Era of RF Spin Feeds */

=Az-El Mount 2.1 m Dishes=

==Testing RF Spin Feed==
On 2023 Mar 12 we are testing a new feed using antenna 3. This feed is manufactured by RF Spin, and is a Quad-Ridge Flared-Horn (QRFH) feed. This dual-polarization feed is rated for 1-18 GHz, but the beam gets quite narrow at higher frequencies, so we can expect under-illumination at the higher frequencies.

===Pointing/Focus Procedure===
Today is the first test of the feed on an antenna, so our procedure will be to first mount the feed (orientation is 90-degrees uncertain, but that can be determined by cross-correlation with other dishes), then do a SOLPNTCAL to check pointing, update the pointing (possibly for several iterations), then attempt to adjust focus. At the end of that procedure, we should have a good idea of the pointing performance vs. frequency. I am hoping to find that the pointing (primary beam) is very stable and uniform over frequency.

The feed has been mounted and both a GAINCAL and SOLPNTCAL have been done. It seems we also need a SKYCAL although I thought the code would allow that to be missing. I'll try to fix this later, but for now I also ran a SKYCAL. The calibration now completes.

[[File:Explanation_Fig.png|thumb|400px|Explanation for apparently strange measurements. (a) When near the meridian, and RA/Dec sweep is aligned 45 degrees from the E-plane of the feeds so both sweeps and both feeds give similar beam sizes. (b) When well past the meridian, the RA/Dec axes are tilted relative to the AzEl-mounted feeds, so the RA sweep gives a narrow X beam and a wide Y beam while the Dec sweep gives the opposite behavior.]]

'''1.''' The result of the first observation, filename IDB20230312165723, is that the beamwidth is very broad, around twice the nominal primary beamwidth. This might be due to being way out of focus, or it may be the under-illumination. We have now moved the feed about 1" (2.5 cm) farther from the dish.
<gallery mode="nolines">
File:RFSpin_test1_X_165724.png|thumb|100px|Test 1 X_polarization beam size for ants 1-4.
File:RFSpin_test1_Y_165724.png|thumb|100px|Test 1 Y_polarization beam size for ants 1-4.
File:RFSpin_test1_Xoffset_165724.png|thumb|400px|Test 1 X_polarization pointing offset for ant 3.
File:RFSpin_test1_Yoffset_165724.png|thumb|400px|Test 1 Y_polarization pointing offset for ant 3.
File:RFSpin_test1_XYcalfac_165724.png|thumb|100px|Test 1 Cal factor plot for ants 1-4.
</gallery>

'''2.''' The result of the second observation, filename IDB20230312200219, is that the beamwidth is much closer to nominal (!), but strangely the pointing behavior is different for the X feed than for the Y feed. But I'll try moving the feed another 0.5" (1.25 cm) farther and see what happens.
<gallery mode="nolines">
File:RFSpin_test2_X_200220.png|thumb|100px|Test 2 X_polarization beam size for ants 1-4.
File:RFSpin_test2_Y_200220.png|thumb|100px|Test 2 Y_polarization beam size for ants 1-4.
File:RFSpin_test2_Xoffset_200220.png|thumb|400px|Test 2 X_polarization pointing offset for ant 3.
File:RFSpin_test2_Yoffset_200220.png|thumb|400px|Test 2 Y_polarization pointing offset for ant 3.
File:RFSpin_test2_XYcalfac_200220.png|thumb|100px|Test 2 Cal factor plot for ants 1-4.
</gallery>

'''3.''' The result of the third observation, filename IDB20230312205319, is that the beamwidth in one axis is broad again, so things seem to have gotten worse relative to the second observation. I am going to try to split the difference between the first two, i.e. move the feed 0.75" toward the dish relative to its current position.
<gallery mode="nolines">
File:RFSpin_test3_X_205320.png|thumb|100px|Test 3 X_polarization beam size for ants 1-4.
File:RFSpin_test3_Y_205320.png|thumb|100px|Test 3 Y_polarization beam size for ants 1-4.
File:RFSpin_test3_Xoffset_205320.png|thumb|400px|Test 3 X_polarization pointing offset for ant 3.
File:RFSpin_test3_Yoffset_205320.png|thumb|400px|Test 3 Y_polarization pointing offset for ant 3.
File:RFSpin_test3_XYcalfac_205320.png|thumb|100px|Test 3 Cal factor plot for ants 1-4.
</gallery>

'''4.''' The result of the fourth observation, filename IDB20230312213919, is worse in beamwidth on some axes, so I will go back away from the dish again. I got a bit lost in positioning the feed. I think it will be a bit farther out from the dish than the 1" position, so intermediate between 1" and 1.5".
<gallery mode="nolines">
File:RFSpin_test4_X_213920.png|thumb|100px|Test 4 X_polarization beam size for ants 1-4.
File:RFSpin_test4_Y_213920.png|thumb|100px|Test 4 Y_polarization beam size for ants 1-4.
File:RFSpin_test4_Xoffset_213920.png|thumb|400px|Test 4 X_polarization pointing offset for ant 3.
File:RFSpin_test4_Yoffset_213920.png|thumb|400px|Test 4 Y_polarization pointing offset for ant 3.
File:RFSpin_test4_XYcalfac_213920.png|thumb|100px|Test 4 Cal factor plot for ants 1-4.
</gallery>

'''5.''' The result of the fifth observation, filename IDB20230312222119, is still a large beamwidth on some axes. It is not clear to me what might be the cause of this. The gaussian fits look good, but the widths are clearly varying a lot on X feed RA and Y feed Dec. The sizes for the other axes are much narrower and very steady.
<gallery mode="nolines">
File:RFSpin_test5_X_222120.png|thumb|100px|Test 5 X_polarization beam size for ants 1-4.
File:RFSpin_test5_Y_222120.png|thumb|100px|Test 5 Y_polarization beam size for ants 1-4.
File:RFSpin_test5_Xoffset_222120.png|thumb|400px|Test 5 X_polarization pointing offset for ant 3.
File:RFSpin_test5_Yoffset_222120.png|thumb|400px|Test 5 Y_polarization pointing offset for ant 3.
File:RFSpin_test5_XYcalfac_222120.png|thumb|100px|Test 5 Cal factor plot for ants 1-4.
</gallery>

===2023 Mar 13 Focus Tests===
We have figured out that the weirdness of the previous tests was that we were doing an RA-Dec cross pattern but the feeds are moving on an AzEl mount, so their orientation was changing for each test relative to the search pattern. This is coupled with a VERY different beam size in the parallel and cross orientations, so the axis that was affected most kept moving. I have arranged to do the cross pattern in AzEl, and now we are consistently getting the same beam size for both feeds, and it should not change with time. So I am hopeful that a new focus search will give more consistent and comparable results.

We are doing a new series of tests where the focus distance will start at the position farthest from the dish and move in (toward the dish, so farther out on the studs) 1 cm at a time. Rather than doing the analysis between tests, which is quite time consuming, we will just do all of the tests at once, one after another, and I'll do the analysis afterwards.

[[File:RFSpin_bsize_20230313.png|800px|left|'''Beamsize Test Results:''' ''top:'' X beamsize in Az direction vs. focus distance. ''row 2:'' X beamsize in El direction. ''row 3:'' Y beamsize in Az direction. ''bottom:'' Y beamsize in El direction. The nominal beam size for a 2.1-m dish is the orange curve in each plot. Note the search bounds are set not to exceed twice nominal).]]

[[File:RFSpin_offsets_20230313.png|800px|left|'''Pointing Offset Test Results:''' ''top:'' X offsets in Az direction vs. focus distance. ''row 2:'' X offsets in El direction. ''row 3:'' Y offsets in Az direction. ''bottom:'' Y offsets in El direction. The solar disk size is +/- 0.25 degree.]]

Test 1: 20:24:57 77 cm from dish

Test 2: 20:40:59 76 cm from dish

Test 3: 20:59:13 75 cm from dish

Test 4: 21:10:11 74 cm from dish

Test 5: 21:21:16 73 cm from dish

Test 6: 21:33:01 72 cm from dish

Test 7: 21:44:31 71 cm from dish

Test 8: 21:56:25 70 cm from dish

Test 9: 22:07:11 69 cm from dish

Test 10: 22:18:21 68 cm from dish

Test 11: 22:30:39 67 cm from dish

Test 12: 22:43:11 66 cm from dish

Test 13: 23:04:55 65 cm from dish

Test 14: 23:18:16 64 cm from dish

'''Results:''' The results are shown in the two figures above and are quite regular and understandable. The best focus is clearly around 69 cm from the dish, with the beamsize being larger than nominal in both axes. However, the earlier tests clearly show that the E-plane feed beamwidth is larger on the dish (illuminates more of the dish), and hence smaller on the sky, so the beamsize in that direction is more or less nominal. The B-plane feed beamwidth is smaller on the dish (illuminates only the central part of the dish), and hence nearly twice as large as the nominal size on the sky.

===Phase Calibration===
Once the best pointing and focus have been found, we will observe a calibrator and check the delays. I tried this on 2023 Mar 12 when the focus was not correctly set, in the file IDB20230312224929. This resulted in an "okay" delay without modification, which is interesting. However, when I plotted the Ant 14 - Ant 3 phase it was not flat with frequency, but showed the characteristic U shape indicating a change in feed phase center vs. frequency. The U was much less pronounced than that of the Tecom feeds relative to the 27-m feed horns, so presumably the feed phase center has less of a meander than the Tecom feeds. This exercise needs to be repeated, but is postponed until tomorrow (2023 Mar 15) due to rain today.

===2023 Jul 22 Tests of Feed with Radome===
On 21 July, Owen got our new radome-equipped feed mounted on Ant 11, so I spent 21 and 22 July working on pointing and delays. The feed seems to be performing nominally, with the expected oval-shaped beam that is twice as wide in the B plane (because the feed pattern is twice as narrow, which under-illuminates the dish). Since Ant 11 is an equatorial mount, it is not necessary to use the Az-El sweep pattern to measure the beam size. Below are the results after adjusting the pointing. Note that this measurement indicates that the feed is rotated 45 degrees from what it should be, showing the maximally different beam sizes for orthogonal directions of a + pattern instead of the roughly equal responses expected of an X pattern.
<gallery mode="nolines">
File:20230722-Xfeed-beamsize.png | thumb | 400px |
File:20230722-Yfeed-beamsize.png | thumb | 400px |
</gallery>

==Pointing in the Era of RF Spin Feeds==
We have purchased 13 RF Spin feeds equipped with radome. These feeds are to replace the many burnt feeds, and we will fit out the entire array with them. However, their elongated feed pattern is causing problems with determining optimum pointing using our current scheme, and so they require a new method of pointing calibration. The problem stems from the fact that the feed pattern center (x direction, say) shifts as the other (y coordinate) changes, so determining a center from a simple RA-Dec cross pattern doesn't work. As a check, I performed a grid of off-point measurements that demonstrates the highly elliptical feed pattern as shown below for the feed on Ant 11.
<gallery mode="nolines">
File:20231013-Xfeed-beampattern.png | thumb | 400px |
File:20231013-Yfeed-beampattern.png | thumb | 400px |
</gallery>

A better way to do the search is to rotate the cross pattern to align with the feed axes (which are in an X shape relative to their coordinate axes) as shown in the figure at right.
[[File:Explanation_Fig2.png|thumb|150px|New Pointing Search Pattern. Sweeping in this way means that the center of the pattern in one dimension remains in the same place as the offset in the other dimension changes. This will also provide a stable measurement of the beam widths in the two orthogonal directions for each polarization.]]
The problem is that this alignment needs to be done with offsets in RA-Dec for the equatorial dishes and in Az-El for the AzEl dishes. Also, the analysis of the data becomes a bit more complicated. But since this is obviously the right thing to do, I will proceed with the idea. Taking the data will be easy enough using the already established means of creating offsets in a trajectory file, sending it to the Az-El dishes via a file with a .azel extension, and to the equatorial dishes via a file with a .radec extension. However, the Az coordinates should be increased by Az/cos(El), and the RA coordinates should be increased by RA/cos(Dec), so these would have to be calculated for the date/time in question. That means writing a routine to create the files on the fly. The analysis is not that different from what I do now, but with a few important changes such as calculating the vector offset length and keeping track of the fact that RA and Az offsets have opposite signs!

==More Focus Tests (2023-Dec-04)==
antenna focus posn start time
ANT 4 6.5 cm 21:32 UT
ANT 4 7.5 cm 21:47 UT
ANT 4 8.5 cm 21:59 UT
ANT 4 9.5 cm 22:11 UT
ANT 4 10.5 cm 22:25 UT
ANT 4 12.5 cm 22:45 UT
'''AAGGHHH''' the recording was not going, so none of the above was recorded. We'll have to do it again tomorrow...

=Equatorial Mount 2.1 m Dishes=
EOVSA comprises 8 newer azimuth-elevation-mounted 2.1 m dishes (plus currently a 9th one, the South Pole dish), and 5 older equatorial-mounted 2.1 m dishes. This document describes some of the important differences for these older dishes.
===Parallactic angle===
The equatorial mounts were outfitted with the same reflector as used for the newer dishes, so that they function in the same way, except that their feeds are fixed in orientation on the sky while the feeds on the newer azel dishes rotate due to the parallactic angle. This angle is computed by the schedule (in stateframe.py), for the current pointing coordinates of each antenna, and inserted into the stateframe as Sche_Data_Chi (SQL naming convention), or sf[‘Schedule’][‘Data’][‘Chi’] (python naming convention), defined as the angle of the azel dish feed relative to an equatorial mount. It should be noted that it is calculated for all antennas, independent of whether the dish is an azel or equatorial mount. For a given azimuth and elevation, the paralactic angle is computed from
<center><math>\chi=\arctan 2(-\cos\lambda \sin a , \sin\lambda \cos e- \cos \lambda \sin e\cos a ) </math></center>

where <math> \lambda</math> = latitude (37.233170 degrees for OVRO), <math>a</math> = azimuth, and <math>e</math> = elevation. The arctan2 function resolves the 180-degree ambiguity. Note that any baseline involving two dissimilar dishes, the phase will rotate according to the parallactic angle, and will need to be corrected by the DPP prior to writing to the Miriad database. The default phase will be that of the azel dishes—that is, baselines with one azel and one equatorial dish will be phase-corrected to correspond to the phase as measured by two azel dishes. [This statement will need to be tested, and possibly amended if it is not correct.]

===Pointing of the equatorial-mount dishes—step size===
The equatorially-mounted dishes have a step-motor drive system, consisting of a motor of ''s'' = 200 steps/revolution, followed by a harmonic drive (a complication is that we have two DIFFERENT harmonic ratios in use, three dishes with ''h'' = 100:1 and two with ''h'' = 160:1). These motors drive a 20-tooth sprocket gear and meshes with a chain having the equivalent of 225 “teeth” in one revolution, for a further reduction ''r'' = 225:20. In addition, we are running the motors with a 16:1 microstepping ratio (<math>\mu</math>), which means that 16 microsteps are needed for one motor step. It is these microsteps that are counted by the system. The resulting of microsteps/degree, then, is
<center><math>n=\mu shr/360 </math></center>
This makes a nice round number, ''n'' = 10000 steps/degree for ''h'' = 100:1, and ''n'' = 16000 steps/degree for ''h'' = 160:1. Currently, Ants 9, 11 and 13 have 10000 steps/degree, while Ants 10, and ultimately 12 will have 16000 steps/degree. These values are given in the crio.ini file.
Obviously, these are nominal values, and the true step size could be slightly different. The step size needs to be part of the pointing parameter solution.

===Pointing of the equatorial-mount dishes—restricted sky coverage===
The equatorial-mount dishes have a restricted sky coverage relative to the azel dishes, given in terms of hour angle limits and declication limits. The precise limits (prior to any pointing corrections) can be determined by adjusting the “hard limits” (limit switches) to trigger just before the antenna hits the stops, and reading the angles at those stopped points. In order to achieve the greatest sky coverage, the hard limits should be set as close as possible to the stops, but with due regard for possible collisions of cables and other obstructions by the mount. In particular, the thick conduit on the north side of the mounts can interfere with the counter-weights when close to the stops, so the limit switches must be set somewhat away from the stops to allow the counter-weights to clear. This has been done with some care on antennas 9 and 10, with the following results (by way of example). The “soft limits” are then selected to stop the motion programmatically just before the limit switch would trigger. It is very important that the motors never reach the hard stops, since that causes the motor to stall while still counting, and hence the step count is compromised. The pointing is only good if the step count is known.
{| class="wikitable"
!Axis
!Ant 9 Hard Limit
!Ant 9 Soft Limit
!Ant 10 Hard Limit
!Ant 10 Soft Limit
|-
| HA Low
| -59.81
| -59.5
| -58.7
| -58.0
|-
| HA High
| +58.33
| +58.0
| +59.3
| +59.0
|-
| Dec Low
| -24.28
| -24.0
| -24.27
| -24.0
|-
| Dec Hi
| +45.43
| +45.0
| +46.25
| +46.0
|-
|}

One concern is that, once the pointing coefficients (and step size) are determined, the angular positions shift somewhat. It would be better to have these hard- and soft-limits not change just because of pointing coefficient adjustments. This will require some thought.
One consequence of this restricted sky coverage is that there will be times (especially in the summer) when some of the dishes cannot reach the Sun or calibrator. With the current set up, when a position is requested that cannot be reached by a dish, it will go as close to the position as possible and then just wait there. The position error can be used to determine which dishes are not tracking. For calibration, all calibrator sources will need to be chosen to respect the equatorial dishes, however, since the 27-m antennas also have this same sky coverage limitation. Therefore, the schedule, which chooses the “best” calibrator automatically, must be set to use the above sky coverage limitation.
Another, rather serious consequence of the restricted sky coverage is that the SOLPNTCAL procedure, which currently runs twice per day, works by off-pointing the dishes by +/- 5 degrees from the Sun in both RA and Dec. Since the south limit of the dishes is only -24 degrees, the dishes will not be able to reach -5 degrees from Sun center whenever the Sun is below declination -19 degrees. This is a date range of roughly Nov 18-Jan 25! During this period, the equatorial-mount dishes will not be able to do a SOLPNTCAL. It could be possible to somehow adjust the procedure to allow some sort of analysis (full HA and half of Dec, for example).

===Pointing of the equatorial-mount dishes—star pointing===
I made an attempt to observe stars with Ant 9, but was not happy with the constant vibrations, which cause the stars to be linear rather than round. I discussed it with Kjell, and he had a new mount for the telescope made (Figure 1), which will go in place of the feed package. With luck, this should allow for much less vibrational motion and hence result in much better star images. I plan to do a first test on Ant 9 tonight.
[[File: new_ telescope_mount.png|thumb|600px|Figure 1: The new mount for the optical telescope, to be put in place of the radio front-end receiver. This should greatly reduce vibrations that lead to non-circular stars.]]

In addition, I updated the startracktable() routine in readbsc.py to account for the reduced sky coverage of the equatorial-mount dishes, since my earlier attempt did not do this, and the antenna spent a lot of time at the limits.

= Debugging =
Ant 12 (the SPASRT antenna) may need its turn count adjusted. To do this, connect to its web page and change parameter 20.16. If its current turn count is 2, set it to 1 and reboot. If it is currently 1, set it to 2 and reboot.

Owens Valley Solar Arrays

2023-12-02T16:29:45Z

Dgary: /* OVRO-LWA Solar-Dedicated Spectroscopic Imager */

Tohban OVRO-LWA Imaging Tutorial

2023-11-22T19:36:42Z

Dgary: /* Calibration and Imaging Script */

=Initial Setup=
The OVRO-LWA has three solar modes that can operate concurrently. These are (1) the beamformer, which creates a high-resolution spectrogram of the solar activity each day, (2) a slow visibility mode that records data in CASA ms format for all 352 antennas and all 3072 frequencies at 10-s cadence, and (3) a fast visibility mode that records data for a 48-antenna subset (generally the outer antennas) and 768 frequencies at 1-s cadence. The recorders that record the data are all activated separately, so it is not guaranteed that data from all three modes are available at any one time. Also, because of the vast data volume most of the recorded data are not saved, but rather are overwritten after a day or so, hence any data that are wanted must be explicitly saved by copying it to another location. Again because of the large volume of data, such copying is too slow to save much data (at least at present), so we can generally save only about an hour of data per day.

'''Note: This tutorial only describes how to work with the slow visibility data at the moment.'''

==Python Environment==
The imaging pipeline is written in Python 3, so in order to use it one must set up a Python 3 environment. These instructions assume you are working in your own home directory on the Pipeline machine at OVRO. First enter the bash shell if you are not already in it. Type <code>echo $0</code> to see what shell you are in. If that returns something other than -bash, type <code>bash</code> to enter the shell. Next check if you have the line <code>alias loadpyenv3.8='source /home/user/.setenv_pyenv38'</code> in your ~/.bash_aliases file. If not, add it using your favorite editor, then activate it with <code>source ~/.bash_aliases</code>. From there, you can type <code>loadpyenv3.8</code> to enter the Python 3.8 environment. Finally, from your home folder, type <code> git clone https://github.com/binchensun/ovro-lwa-solar </code> to install the OVRO-LWA code. To test your Python environment, log out and log in again fresh, then type
<pre>
$> loadpyenv3.8
$> ipython --pylab
import sys
sys.path.append('/home/dgary/ovro-lwa-solar') # Replace with your own home directory
import solar_pipeline
</pre>
If that succeeds, you should be ready to proceed.

==Where to Find Data==
The next step is to find the data you want to work with. You will need some calibration data as well as the solar data for your target date. As of this writing, the existing solar data on Pipeline, is in two separate places: /nas5/ovro-lwa-data (data up to 2023-09-03) and /nas6/ovro-lwa-data (data from 2023-09-18 and later). All of the existing beamformed data (spectrograms) are in /nas5/ovro-lwa-data/beam/beam-data.

'''This tutorial uses the example of the type II burst on 2023-07-28.'''

==Examining the Spectrogram for Your Date==
It is good practice to examine the spectrogram for your date/time, to guide your selection of frequencies and times to use for imaging. You can check the folders and subfolders in /nas5/ovro-lwa-data/beam/beam-data to see what files exist. Note that the filenames have the Modified Julian Data (mjd) followed by hours, minutes, seconds in the format <mjdday>.<hh><mm><ss>?????????? where the ? indicate more digits of the fraction of a second. The type II burst we are interested in started around 15:43 UT on 2023 July 28, which is MJD 060154, so the file we want is <code>/nas5/ovro-lwa-data/beam/beam-data/202307/beam20230728/060153_152717110834334d2be</code>, which starts at 15:27:17 UT. Generally these files contain 30 min of data. The type II continues into the next file, which is <code>060153_1558172229518804396</code>.

To read and display this file, in iPython type
[[File:20230728-type-II.png|300px|left|'''2023 July 28 Type II event spectrogram''']] <pre>
import sys # If not already loaded
sys.path.append('/nas5/ovro-lwa-data/beam/software/')
from lwa import lwa_read, lwa_plot
datadir = '/nas5/ovro-lwa-data/beam/beam-data/202307/beam20230728/'
data = lwa_read(datadir+'060153_152717110834334d2be', stokes='IV', timebin=1, freqbin=4)
lwa_plot(data, vmax=15000,vmin=10)
</pre>
which defaults to log-scaled amplitudes and viridis color table for stokes I and linear-scaled amplitudes and grayscale for stokes V, as shown at left. You can examine lwa_plot? for more options. 
 
 

==Calibration and Imaging Script==
The script below assumes some previous setup. First, a "home" directory needs to be created and the script must be run from that directory. Because of the large amount of disk space required, create your "home" directory on /data1. Mine is /data1/dgary/OVRO-LWA/20230728_workdir. Before running the script, you'll need to change the 7 lines indicated with the '''***Change''' comments.
# The first such line is the list of frequency bands you want to image. In this case I have all 13 useful bands. Frequencies below 27 MHz rarely image well and in many cases we did not save the data for those frequencies anyway.
# The second is a string representing the date of the event, including an underscore (this is part of a filename).
# The third line is a list of solar times. These times have to exactly match existing filenames, so you'll have to do a listing of the data directory to check them. ''Warning: Doing a listing of the entire data directory is time consuming and not useful, since there are many thousands of files there.'' Instead, use something like: <code>ls /nas5/ovro-lwa-data/20230728/slow/20230728_1553*</code> to limit the number of files returned.
# The fourth line is the date string of the calibration data. This will almost always be the same as the date string of the data, but it is possible to use a calibration from a different date if not too far apart.
# The fifth line is the time of the calibration data. Again, this must exist. Usually the calibration is done at night so the time will be quite different, e.g. 0500 UT, and a command like <code>ls /nas5/ovro-lwa-data/20230728/slow | head -20</code> will list the first 20 files in the folder, which are likely the calibration files. Unfortunately, no nighttime calibration exists for this date, so I had to use a daytime time, 15:40 UT.
# The sixth line is the path to the data.
# The seventh line is the path to the calibration data, again usually the same as that for the data.
<pre>
import os, glob
import utils
from time import time
import solar_pipeline

freqs=[27,32,36,41,46,50,55,59,64,69,73,78,82] # ***Change to the bands you want to image
datstr = '20230728_' # ***Change to the date of your event
solar_times = ['155306','155316','155326'] # ***Change to the times to use for solar imaging -- these times must exist!
caldatstr = '20230728_' # ***Change to the date of your cal data
cal_time = '154003' # ***Change to the time for your calibration
datapath = '/nas5/ovro-lwa-data/20230728/slow/' # ***Change to path to your data
calpath = '/nas5/ovro-lwa-data/20230728/slow/' # ***Change to path to your calibration data

home=os.getcwd()
for solar_time in solar_times:
for freq in freqs:
calib_ms=caldatstr+cal_time+'_'+str(freq)+"MHz.ms" # Will be copied from calpath
solar_ms=datstr+solar_time+'_'+str(freq)+"MHz.ms" # Will be copied from datapath
bcal='caltables/'+calib_ms.replace('ms','bcal') # Will be created if it doesn't already exist
imagename=datstr+solar_time+'_'+str(freq)+"MHz"
image_fold = 'images/'

# Create frequency folder, if it doesn't exist
freq_fold=str(freq)+"MHz"
if not os.path.isdir(freq_fold):
os.mkdir(freq_fold)

# Copy the solar data for this time (will be deleted later)
print('Copying solar data to frequency folder')
os.system("cp -r "+os.path.join(datapath,solar_ms)+"* "+freq_fold+"/")
# Copy the calibration data (will be deleted later)
print('Copying calibration data to frequency folder')
os.system("cp -r "+os.path.join(datapath,calib_ms)+"* "+freq_fold+"/")

os.chdir(freq_fold)
if not os.path.isdir(image_fold):
os.mkdir(image_fold)
if not os.path.isfile(bcal):
bcal = None
if not os.path.isdir('caltables'):
os.mkdir('caltables')
if not os.path.isdir('final_ms'):
os.mkdir('final_ms')

try:
solar_pipeline.image_ms(solar_ms=solar_ms,calib_ms=calib_ms,bcal=bcal,\
imagename=imagename,do_final_imaging=False,logfile='analysis_'+str(freq)+'.log')
msname = datstr+solar_time+'_'+str(freq)+'MHz_final.ms'
os.system("mv *calibrated_selfcalibrated_sun_only_sun_selfcalibrated_sun_only.ms final_ms/"+msname)
os.system("rm -rf *.ms* *.fits *.gcal *.cl *.badants")
# Make 10 images for this band (integrates over 19 or 20 subchannels, bandwidth ~0.4545 MHz)
os.system('wsclean -no-dirty -size 1024 1024 -scale 1arcmin -weight uniform -minuv-l 10 -name '+imagename+' -niter 10000 -mgain 0.8 -beam-fitting-size 1 -pol I -join-channels -channels-out 10 final_ms/'+msname)
# Convert images to heliocentric, move them to the final image folder, and delete all fits files
files = glob.glob('*-image.fits')
for imgfile in files:
utils.correct_primary_beam('final_ms/'+msname, imgfile.split('-image.fits')[0])
helio_image = utils.convert_to_heliocentric_coords('final_ms/'+msname, imgfile)
os.system('mv '+helio_image+' '+image_fold)
os.system('rm *.fits')
except:
pass
os.chdir(home)

</pre>

== What Happens When You Run the Script ==
One way to run this script is to cut-and-paste into a file, say process.py, and then in an iPython session type
<pre>
import sys
sys.path.append('/home/dgary/ovro-lwa-solar') # Change to your path where you cloned the git repository
run 'process.py'
</pre>
If all goes well, after many hours you will have all of your images. If you examine the script, you will see that there are two loops, an inner one over frequency and an outer one over time. The inner loop will create a subdirectory for the frequency it is working on (first will be subdirectory named 27MHz), then do the calibration for that frequency and create a subfolder caltables with a .bcal file in it. Luckily, this only has to be done once and then the .bcal file will be used for subsequent times so its creation will be skipped. Other files with .gcal extension will be created for the first data time, and also will be reused for subesquent times up to one hour later. When a new .gcal file is needed, the pipeline will create it automatically for you. The gain files take about 10 min for each frequency, but again is only done once for an hour of data. After the calibration is complete, <code>wsclean</code> is used to create images (in 10 subbands of each 4.5 GHz band, plus an MFS image integrated over the whole band). They are converted to heliographic coordinates and you will find them in 27MHz/images when done. This takes another 10 minutes or so.

When all of that is done for the first frequency, the whole process starts again for the next, and so one until all images for the first time are done. In this example, then, it will take about 20/min per frequency * 13 frequencies = 260 minutes (> 4 hours!) to make all 143 images for the first time (10 images per band + 1 MFS image). For subsequent times, though, the calibration step is skipped so each subsequent time will take 10 min * 13 frequencies (around 2 hours). That means the entire script will run in about 8 hours and produce 429 images.

Tohban OVRO-LWA Imaging Tutorial

2023-11-09T16:41:37Z

Dgary: /* Calibration and Imaging Script */

=Initial Setup=
The OVRO-LWA has three solar modes that can operate concurrently. These are (1) the beamformer, which creates a high-resolution spectrogram of the solar activity each day, (2) a slow visibility mode that records data in CASA ms format for all 352 antennas and all 3072 frequencies at 10-s cadence, and (3) a fast visibility mode that records data for a 48-antenna subset (generally the outer antennas) and 768 frequencies at 1-s cadence. The recorders that record the data are all activated separately, so it is not guaranteed that data from all three modes are available at any one time. Also, because of the vast data volume most of the recorded data are not saved, but rather are overwritten after a day or so, hence any data that are wanted must be explicitly saved by copying it to another location. Again because of the large volume of data, such copying is too slow to save much data (at least at present), so we can generally save only about an hour of data per day.

'''Note: This tutorial only describes how to work with the slow visibility data at the moment.'''

==Python Environment==
The imaging pipeline is written in Python 3, so in order to use it one must set up a Python 3 environment. These instructions assume you are working in your own home directory on the Pipeline machine at OVRO. First enter the bash shell if you are not already in it. Type <code>echo $0</code> to see what shell you are in. If that returns something other than -bash, type <code>bash</code> to enter the shell. Next check if you have the line <code>alias loadpyenv3.8='source /home/user/.setenv_pyenv38'</code> in your ~/.bash_aliases file. If not, add it using your favorite editor, then activate it with <code>source ~/.bash_aliases</code>. From there, you can type <code>loadpyenv3.8</code> to enter the Python 3.8 environment. Finally, from your home folder, type <code> git clone https://github.com/binchensun/ovro-lwa-solar </code> to install the OVRO-LWA code. To test your Python environment, log out and log in again fresh, then type
<pre>
$> loadpyenv3.8
$> ipython --pylab
import sys
sys.path.append('/home/dgary/ovro-lwa-solar') # Replace with your own home directory
import solar_pipeline
</pre>
If that succeeds, you should be ready to proceed.

==Where to Find Data==
The next step is to find the data you want to work with. You will need some calibration data as well as the solar data for your target date. As of this writing, the existing solar data on Pipeline, is in two separate places: /nas5/ovro-lwa-data (data up to 2023-09-03) and /nas6/ovro-lwa-data (data from 2023-09-18 and later). All of the existing beamformed data (spectrograms) are in /nas5/ovro-lwa-data/beam/beam-data.

'''This tutorial uses the example of the type II burst on 2023-07-28.'''

==Examining the Spectrogram for Your Date==
It is good practice to examine the spectrogram for your date/time, to guide your selection of frequencies and times to use for imaging. You can check the folders and subfolders in /nas5/ovro-lwa-data/beam/beam-data to see what files exist. Note that the filenames have the Modified Julian Data (mjd) followed by hours, minutes, seconds in the format <mjdday>.<hh><mm><ss>?????????? where the ? indicate more digits of the fraction of a second. The type II burst we are interested in started around 15:43 UT on 2023 July 28, which is MJD 060154, so the file we want is <code>/nas5/ovro-lwa-data/beam/beam-data/202307/beam20230728/060153_152717110834334d2be</code>, which starts at 15:27:17 UT. Generally these files contain 30 min of data. The type II continues into the next file, which is <code>060153_1558172229518804396</code>.

To read and display this file, in iPython type
[[File:20230728-type-II.png|300px|left|'''2023 July 28 Type II event spectrogram''']] <pre>
import sys # If not already loaded
sys.path.append('/nas5/ovro-lwa-data/beam/software/')
from lwa import lwa_read, lwa_plot
datadir = '/nas5/ovro-lwa-data/beam/beam-data/202307/beam20230728/'
data = lwa_read(datadir+'060153_152717110834334d2be', stokes='IV', timebin=1, freqbin=4)
lwa_plot(data, vmax=15000,vmin=10)
</pre>
which defaults to log-scaled amplitudes and viridis color table for stokes I and linear-scaled amplitudes and grayscale for stokes V, as shown at left. You can examine lwa_plot? for more options. 
 
 

==Calibration and Imaging Script==
The script below assumes some previous setup. First, a "home" directory needs to be created and the script must be run from that directory. Because of the large amount of disk space required, create your "home" directory on /data1. Mine is /data1/dgary/OVRO-LWA/20230728_workdir. Before running the script, you'll need to change the 7 lines indicated with the '''***Change''' comments.
# The first such line is the list of frequency bands you want to image. In this case I have all 13 useful bands. Frequencies below 27 MHz rarely image well and in many cases we did not save the data for those frequencies anyway.
# The second is a string representing the date of the event, including an underscore (this is part of a filename).
# The third line is a list of solar times. These times have to exactly match existing filenames, so you'll have to do a listing of the data directory to check them. ''Warning: Doing a listing of the entire data directory is time consuming and not useful, since there are many thousands of files there.'' Instead, use something like: <code>ls /nas5/ovro-lwa-data/20230728/slow/20230728_1553*</code> to limit the number of files returned.
# The fourth line is the date string of the calibration data. This will almost always be the same as the date string of the data, but it is possible to use a calibration from a different date if not too far apart.
# The fifth line is the time of the calibration data. Again, this must exist. Usually the calibration is done at night so the time will be quite different, e.g. 0500 UT, and a command like <code>ls /nas5/ovro-lwa-data/20230728/slow | head -20</code> will list the first 20 files in the folder, which are likely the calibration files. Unfortunately, no nighttime calibration exists for this date, so I had to use a daytime time, 15:40 UT.
# The sixth line is the path to the data.
# The seventh line is the path to the calibration data, again usually the same as that for the data.
<pre>
import os, glob
import utils
from time import time
import solar_pipeline

freqs=[27,32,36,41,46,50,55,59,64,69,73,78,82] # ***Change to the bands you want to image
datstr = '20230728_' # ***Change to the date of your event
solar_times = ['155306','155316','155326'] # ***Change to the times to use for solar imaging -- these times must exist!
caldatstr = '20230728_' # ***Change to the date of your cal data
cal_time = '154003' # ***Change to the time for your calibration
datapath = '/nas5/ovro-lwa-data/20230728/slow/' # ***Change to path to your data
calpath = '/nas5/ovro-lwa-data/20230728/slow/' # ***Change to path to your calibration data

home=os.getcwd()
for solar_time in solar_times:
for freq in freqs:
calib_ms=caldatstr+cal_time+'_'+str(freq)+"MHz.ms" # Will be copied from calpath
solar_ms=datstr+solar_time+'_'+str(freq)+"MHz.ms" # Will be copied from datapath
bcal='caltables/'+calib_ms.replace('ms','bcal') # Will be created if it doesn't already exist
imagename=datstr+solar_time+'_'+str(freq)+"MHz"
image_fold = 'images/'

# Create frequency folder, if it doesn't exist
freq_fold=str(freq)+"MHz"
if not os.path.isdir(freq_fold):
os.mkdir(freq_fold)

# Copy the solar data for this time (will be deleted later)
print('Copying solar data to frequency folder')
os.system("cp -r "+os.path.join(datapath,solar_ms)+"* "+freq_fold+"/")
# Copy the calibration data (will be deleted later)
print('Copying calibration data to frequency folder')
os.system("cp -r "+os.path.join(datapath,calib_ms)+"* "+freq_fold+"/")

os.chdir(freq_fold)
if not os.path.isdir(image_fold):
os.mkdir(image_fold)
if not os.path.isfile(bcal):
bcal = None
if not os.path.isdir('caltables'):
os.mkdir('caltables')
if not os.path.isdir('final_ms'):
os.mkdir('final_ms')

try:
solar_pipeline.image_ms(solar_ms=solar_ms,calib_ms=calib_ms,bcal=bcal,\
imagename=imagename,do_final_imaging=False,logfile='analysis_'+str(freq)+'.log')
msname = datstr+solar_time+'_'+str(freq)+'MHz_final.ms'
os.system("mv *calibrated_selfcalibrated_sun_only_sun_selfcalibrated_sun_only.ms final_ms/"+msname)
os.system("rm -rf *.ms* *.fits *.gcal *.cl *.badants")
# Make 10 images for this band (integrates over 19 or 20 subchannels, bandwidth ~0.4545 MHz)
os.system('wsclean -no-dirty -size 1024 1024 -scale 1arcmin -weight uniform -minuv-l 10 -name '+imagename+' -niter 10000 -mgain 0.8 -beam-fitting-size 1 -pol I -join-channels -channels-out 10 final_ms/'+msname)
# Convert images to heliocentric, move them to the final image folder, and delete all fits files
files = glob.glob('*-image.fits')
for imgfile in files:
solar_pipeline.correct_primary_beam('final_ms/'+msname, imgfile.split('-image.fits')[0])
helio_image = utils.convert_to_heliocentric_coords('final_ms/'+msname, imgfile)
os.system('mv '+helio_image+' '+image_fold)
os.system('rm *.fits')
except:
pass
os.chdir(home)

</pre>

== What Happens When You Run the Script ==
One way to run this script is to cut-and-paste into a file, say process.py, and then in an iPython session type
<pre>
import sys
sys.path.append('/home/dgary/ovro-lwa-solar') # Change to your path where you cloned the git repository
run 'process.py'
</pre>
If all goes well, after many hours you will have all of your images. If you examine the script, you will see that there are two loops, an inner one over frequency and an outer one over time. The inner loop will create a subdirectory for the frequency it is working on (first will be subdirectory named 27MHz), then do the calibration for that frequency and create a subfolder caltables with a .bcal file in it. Luckily, this only has to be done once and then the .bcal file will be used for subsequent times so its creation will be skipped. Other files with .gcal extension will be created for the first data time, and also will be reused for subesquent times up to one hour later. When a new .gcal file is needed, the pipeline will create it automatically for you. The gain files take about 10 min for each frequency, but again is only done once for an hour of data. After the calibration is complete, <code>wsclean</code> is used to create images (in 10 subbands of each 4.5 GHz band, plus an MFS image integrated over the whole band). They are converted to heliographic coordinates and you will find them in 27MHz/images when done. This takes another 10 minutes or so.

When all of that is done for the first frequency, the whole process starts again for the next, and so one until all images for the first time are done. In this example, then, it will take about 20/min per frequency * 13 frequencies = 260 minutes (> 4 hours!) to make all 143 images for the first time (10 images per band + 1 MFS image). For subsequent times, though, the calibration step is skipped so each subsequent time will take 10 min * 13 frequencies (around 2 hours). That means the entire script will run in about 8 hours and produce 429 images.

Tohban OVRO-LWA Imaging Tutorial

2023-11-09T16:39:57Z

Dgary: /* What Happens When You Run the Script */

=Initial Setup=
The OVRO-LWA has three solar modes that can operate concurrently. These are (1) the beamformer, which creates a high-resolution spectrogram of the solar activity each day, (2) a slow visibility mode that records data in CASA ms format for all 352 antennas and all 3072 frequencies at 10-s cadence, and (3) a fast visibility mode that records data for a 48-antenna subset (generally the outer antennas) and 768 frequencies at 1-s cadence. The recorders that record the data are all activated separately, so it is not guaranteed that data from all three modes are available at any one time. Also, because of the vast data volume most of the recorded data are not saved, but rather are overwritten after a day or so, hence any data that are wanted must be explicitly saved by copying it to another location. Again because of the large volume of data, such copying is too slow to save much data (at least at present), so we can generally save only about an hour of data per day.

'''Note: This tutorial only describes how to work with the slow visibility data at the moment.'''

==Python Environment==
The imaging pipeline is written in Python 3, so in order to use it one must set up a Python 3 environment. These instructions assume you are working in your own home directory on the Pipeline machine at OVRO. First enter the bash shell if you are not already in it. Type <code>echo $0</code> to see what shell you are in. If that returns something other than -bash, type <code>bash</code> to enter the shell. Next check if you have the line <code>alias loadpyenv3.8='source /home/user/.setenv_pyenv38'</code> in your ~/.bash_aliases file. If not, add it using your favorite editor, then activate it with <code>source ~/.bash_aliases</code>. From there, you can type <code>loadpyenv3.8</code> to enter the Python 3.8 environment. Finally, from your home folder, type <code> git clone https://github.com/binchensun/ovro-lwa-solar </code> to install the OVRO-LWA code. To test your Python environment, log out and log in again fresh, then type
<pre>
$> loadpyenv3.8
$> ipython --pylab
import sys
sys.path.append('/home/dgary/ovro-lwa-solar') # Replace with your own home directory
import solar_pipeline
</pre>
If that succeeds, you should be ready to proceed.

==Where to Find Data==
The next step is to find the data you want to work with. You will need some calibration data as well as the solar data for your target date. As of this writing, the existing solar data on Pipeline, is in two separate places: /nas5/ovro-lwa-data (data up to 2023-09-03) and /nas6/ovro-lwa-data (data from 2023-09-18 and later). All of the existing beamformed data (spectrograms) are in /nas5/ovro-lwa-data/beam/beam-data.

'''This tutorial uses the example of the type II burst on 2023-07-28.'''

==Examining the Spectrogram for Your Date==
It is good practice to examine the spectrogram for your date/time, to guide your selection of frequencies and times to use for imaging. You can check the folders and subfolders in /nas5/ovro-lwa-data/beam/beam-data to see what files exist. Note that the filenames have the Modified Julian Data (mjd) followed by hours, minutes, seconds in the format <mjdday>.<hh><mm><ss>?????????? where the ? indicate more digits of the fraction of a second. The type II burst we are interested in started around 15:43 UT on 2023 July 28, which is MJD 060154, so the file we want is <code>/nas5/ovro-lwa-data/beam/beam-data/202307/beam20230728/060153_152717110834334d2be</code>, which starts at 15:27:17 UT. Generally these files contain 30 min of data. The type II continues into the next file, which is <code>060153_1558172229518804396</code>.

To read and display this file, in iPython type
[[File:20230728-type-II.png|300px|left|'''2023 July 28 Type II event spectrogram''']] <pre>
import sys # If not already loaded
sys.path.append('/nas5/ovro-lwa-data/beam/software/')
from lwa import lwa_read, lwa_plot
datadir = '/nas5/ovro-lwa-data/beam/beam-data/202307/beam20230728/'
data = lwa_read(datadir+'060153_152717110834334d2be', stokes='IV', timebin=1, freqbin=4)
lwa_plot(data, vmax=15000,vmin=10)
</pre>
which defaults to log-scaled amplitudes and viridis color table for stokes I and linear-scaled amplitudes and grayscale for stokes V, as shown at left. You can examine lwa_plot? for more options. 
 
 

==Calibration and Imaging Script==
The script below assumes some previous setup. First, a "home" directory needs to be created and the script must be run from that directory. Because of the large amount of disk space required, create your "home" directory on /data1. Mine is /data1/dgary/OVRO-LWA/20230728_workdir. Before running the script, you'll need to change the 7 lines indicated with the '''***Change''' comments.
# The first such line is the list of frequency bands you want to image. In this case I have all 13 useful bands. Frequencies below 27 MHz rarely image well and in many cases we did not save the data for those frequencies anyway.
# The second is a string representing the date of the event, including an underscore (this is part of a filename).
# The third line is a list of solar times. These times have to exactly match existing filenames, so you'll have to do a listing of the data directory to check them. ''Warning: Doing a listing of the entire data directory is time consuming and not useful, since there are many thousands of files there.'' Instead, use something like: <code>ls /nas5/ovro-lwa-data/20230728/slow/20230728_1553*</code> to limit the number of files returned.
# The fourth line is the date string of the calibration data. This will almost always be the same as the date string of the data, but it is possible to use a calibration from a different date if not too far apart.
# The fifth line is the time of the calibration data. Again, this must exist. Usually the calibration is done at night so the time will be quite different, e.g. 0500 UT, and a command like <code>ls /nas5/ovro-lwa-data/20230728/slow | head -20</code> will list the first 20 files in the folder, which are likely the calibration files. Unfortunately, no nighttime calibration exists for this date, so I had to use a daytime time, 15:40 UT.
# The sixth line is the path to the data.
# The seventh line is the path to the calibration data, again usually the same as that for the data.
<pre>
import os, glob
import utils
from time import time
import solar_pipeline

freqs=[27,32,36,41,46,50,55,59,64,69,73,78,82] # ***Change to the bands you want to image
datstr = '20230728_' # ***Change to the date of your event
solar_times = ['155306','155316','155326'] # ***Change to the times to use for solar imaging -- these times must exist!
caldatstr = '20230728_' # ***Change to the date of your cal data
cal_time = '154003' # ***Change to the time for your calibration
datapath = '/nas5/ovro-lwa-data/20230728/slow/' # ***Change to path to your data
calpath = '/nas5/ovro-lwa-data/20230728/slow/' # ***Change to path to your calibration data

home=os.getcwd()
for solar_time in solar_times:
for freq in freqs:
calib_ms=caldatstr+cal_time+'_'+str(freq)+"MHz.ms" # Will be copied from calpath
solar_ms=datstr+solar_time+'_'+str(freq)+"MHz.ms" # Will be copied from datapath
bcal='caltables/'+calib_ms.replace('ms','bcal') # Will be created if it doesn't already exist
imagename=datstr+solar_time+'_'+str(freq)+"MHz"
image_fold = 'images/'

# Create frequency folder, if it doesn't exist
freq_fold=str(freq)+"MHz"
if not os.path.isdir(freq_fold):
os.mkdir(freq_fold)

# Copy the solar data for this time (will be deleted later)
print('Copying solar data to frequency folder')
os.system("cp -r "+os.path.join(datapath,solar_ms)+"* "+freq_fold+"/")
# Copy the calibration data (will be deleted later)
print('Copying calibration data to frequency folder')
os.system("cp -r "+os.path.join(datapath,calib_ms)+"* "+freq_fold+"/")

os.chdir(freq_fold)
if not os.path.isdir(image_fold):
os.mkdir(image_fold)
if not os.path.isfile(bcal):
bcal = None
if not os.path.isdir('caltables'):
os.mkdir('caltables')

try:
solar_pipeline.image_ms(solar_ms=solar_ms,calib_ms=calib_ms,bcal=bcal,\
imagename=imagename,do_final_imaging=False,logfile='analysis_'+str(freq)+'.log')
msname = datstr+solar_time+'_'+str(freq)+'MHz_final.ms'
os.system("mv *calibrated_selfcalibrated_sun_only_sun_selfcalibrated_sun_only.ms final_ms/"+msname)
os.system("rm -rf *.ms* *.fits *.gcal *.cl *.badants")
# Make 10 images for this band (integrates over 19 or 20 subchannels, bandwidth ~0.4545 MHz)
os.system('wsclean -no-dirty -size 1024 1024 -scale 1arcmin -weight uniform -minuv-l 10 -name '+imagename+' -niter 10000 -mgain 0.8 -beam-fitting-size 1 -pol I -join-channels -channels-out 10 final_ms/'+msname)
# Convert images to heliocentric, move them to the final image folder, and delete all fits files
files = glob.glob('*-image.fits')
for imgfile in files:
solar_pipeline.correct_primary_beam('final_ms/'+msname, imgfile.split('-image.fits')[0])
helio_image = utils.convert_to_heliocentric_coords('final_ms/'+msname, imgfile)
os.system('mv '+helio_image+' '+image_fold)
os.system('rm *.fits')
except:
pass
os.chdir(home)

</pre>
== What Happens When You Run the Script ==
One way to run this script is to cut-and-paste into a file, say process.py, and then in an iPython session type
<pre>
import sys
sys.path.append('/home/dgary/ovro-lwa-solar') # Change to your path where you cloned the git repository
run 'process.py'
</pre>
If all goes well, after many hours you will have all of your images. If you examine the script, you will see that there are two loops, an inner one over frequency and an outer one over time. The inner loop will create a subdirectory for the frequency it is working on (first will be subdirectory named 27MHz), then do the calibration for that frequency and create a subfolder caltables with a .bcal file in it. Luckily, this only has to be done once and then the .bcal file will be used for subsequent times so its creation will be skipped. Other files with .gcal extension will be created for the first data time, and also will be reused for subesquent times up to one hour later. When a new .gcal file is needed, the pipeline will create it automatically for you. The gain files take about 10 min for each frequency, but again is only done once for an hour of data. After the calibration is complete, <code>wsclean</code> is used to create images (in 10 subbands of each 4.5 GHz band, plus an MFS image integrated over the whole band). They are converted to heliographic coordinates and you will find them in 27MHz/images when done. This takes another 10 minutes or so.

When all of that is done for the first frequency, the whole process starts again for the next, and so one until all images for the first time are done. In this example, then, it will take about 20/min per frequency * 13 frequencies = 260 minutes (> 4 hours!) to make all 143 images for the first time (10 images per band + 1 MFS image). For subsequent times, though, the calibration step is skipped so each subsequent time will take 10 min * 13 frequencies (around 2 hours). That means the entire script will run in about 8 hours and produce 429 images.

Tohban OVRO-LWA Imaging Tutorial

2023-11-09T16:38:39Z

Dgary: /* What Happens When You Run the Script */

=Initial Setup=
The OVRO-LWA has three solar modes that can operate concurrently. These are (1) the beamformer, which creates a high-resolution spectrogram of the solar activity each day, (2) a slow visibility mode that records data in CASA ms format for all 352 antennas and all 3072 frequencies at 10-s cadence, and (3) a fast visibility mode that records data for a 48-antenna subset (generally the outer antennas) and 768 frequencies at 1-s cadence. The recorders that record the data are all activated separately, so it is not guaranteed that data from all three modes are available at any one time. Also, because of the vast data volume most of the recorded data are not saved, but rather are overwritten after a day or so, hence any data that are wanted must be explicitly saved by copying it to another location. Again because of the large volume of data, such copying is too slow to save much data (at least at present), so we can generally save only about an hour of data per day.

'''Note: This tutorial only describes how to work with the slow visibility data at the moment.'''

==Python Environment==
The imaging pipeline is written in Python 3, so in order to use it one must set up a Python 3 environment. These instructions assume you are working in your own home directory on the Pipeline machine at OVRO. First enter the bash shell if you are not already in it. Type <code>echo $0</code> to see what shell you are in. If that returns something other than -bash, type <code>bash</code> to enter the shell. Next check if you have the line <code>alias loadpyenv3.8='source /home/user/.setenv_pyenv38'</code> in your ~/.bash_aliases file. If not, add it using your favorite editor, then activate it with <code>source ~/.bash_aliases</code>. From there, you can type <code>loadpyenv3.8</code> to enter the Python 3.8 environment. Finally, from your home folder, type <code> git clone https://github.com/binchensun/ovro-lwa-solar </code> to install the OVRO-LWA code. To test your Python environment, log out and log in again fresh, then type
<pre>
$> loadpyenv3.8
$> ipython --pylab
import sys
sys.path.append('/home/dgary/ovro-lwa-solar') # Replace with your own home directory
import solar_pipeline
</pre>
If that succeeds, you should be ready to proceed.

==Where to Find Data==
The next step is to find the data you want to work with. You will need some calibration data as well as the solar data for your target date. As of this writing, the existing solar data on Pipeline, is in two separate places: /nas5/ovro-lwa-data (data up to 2023-09-03) and /nas6/ovro-lwa-data (data from 2023-09-18 and later). All of the existing beamformed data (spectrograms) are in /nas5/ovro-lwa-data/beam/beam-data.

'''This tutorial uses the example of the type II burst on 2023-07-28.'''

==Examining the Spectrogram for Your Date==
It is good practice to examine the spectrogram for your date/time, to guide your selection of frequencies and times to use for imaging. You can check the folders and subfolders in /nas5/ovro-lwa-data/beam/beam-data to see what files exist. Note that the filenames have the Modified Julian Data (mjd) followed by hours, minutes, seconds in the format <mjdday>.<hh><mm><ss>?????????? where the ? indicate more digits of the fraction of a second. The type II burst we are interested in started around 15:43 UT on 2023 July 28, which is MJD 060154, so the file we want is <code>/nas5/ovro-lwa-data/beam/beam-data/202307/beam20230728/060153_152717110834334d2be</code>, which starts at 15:27:17 UT. Generally these files contain 30 min of data. The type II continues into the next file, which is <code>060153_1558172229518804396</code>.

To read and display this file, in iPython type
[[File:20230728-type-II.png|300px|left|'''2023 July 28 Type II event spectrogram''']] <pre>
import sys # If not already loaded
sys.path.append('/nas5/ovro-lwa-data/beam/software/')
from lwa import lwa_read, lwa_plot
datadir = '/nas5/ovro-lwa-data/beam/beam-data/202307/beam20230728/'
data = lwa_read(datadir+'060153_152717110834334d2be', stokes='IV', timebin=1, freqbin=4)
lwa_plot(data, vmax=15000,vmin=10)
</pre>
which defaults to log-scaled amplitudes and viridis color table for stokes I and linear-scaled amplitudes and grayscale for stokes V, as shown at left. You can examine lwa_plot? for more options. 
 
 

==Calibration and Imaging Script==
The script below assumes some previous setup. First, a "home" directory needs to be created and the script must be run from that directory. Because of the large amount of disk space required, create your "home" directory on /data1. Mine is /data1/dgary/OVRO-LWA/20230728_workdir. Before running the script, you'll need to change the 7 lines indicated with the '''***Change''' comments.
# The first such line is the list of frequency bands you want to image. In this case I have all 13 useful bands. Frequencies below 27 MHz rarely image well and in many cases we did not save the data for those frequencies anyway.
# The second is a string representing the date of the event, including an underscore (this is part of a filename).
# The third line is a list of solar times. These times have to exactly match existing filenames, so you'll have to do a listing of the data directory to check them. ''Warning: Doing a listing of the entire data directory is time consuming and not useful, since there are many thousands of files there.'' Instead, use something like: <code>ls /nas5/ovro-lwa-data/20230728/slow/20230728_1553*</code> to limit the number of files returned.
# The fourth line is the date string of the calibration data. This will almost always be the same as the date string of the data, but it is possible to use a calibration from a different date if not too far apart.
# The fifth line is the time of the calibration data. Again, this must exist. Usually the calibration is done at night so the time will be quite different, e.g. 0500 UT, and a command like <code>ls /nas5/ovro-lwa-data/20230728/slow | head -20</code> will list the first 20 files in the folder, which are likely the calibration files. Unfortunately, no nighttime calibration exists for this date, so I had to use a daytime time, 15:40 UT.
# The sixth line is the path to the data.
# The seventh line is the path to the calibration data, again usually the same as that for the data.
<pre>
import os, glob
import utils
from time import time
import solar_pipeline

freqs=[27,32,36,41,46,50,55,59,64,69,73,78,82] # ***Change to the bands you want to image
datstr = '20230728_' # ***Change to the date of your event
solar_times = ['155306','155316','155326'] # ***Change to the times to use for solar imaging -- these times must exist!
caldatstr = '20230728_' # ***Change to the date of your cal data
cal_time = '154003' # ***Change to the time for your calibration
datapath = '/nas5/ovro-lwa-data/20230728/slow/' # ***Change to path to your data
calpath = '/nas5/ovro-lwa-data/20230728/slow/' # ***Change to path to your calibration data

home=os.getcwd()
for solar_time in solar_times:
for freq in freqs:
calib_ms=caldatstr+cal_time+'_'+str(freq)+"MHz.ms" # Will be copied from calpath
solar_ms=datstr+solar_time+'_'+str(freq)+"MHz.ms" # Will be copied from datapath
bcal='caltables/'+calib_ms.replace('ms','bcal') # Will be created if it doesn't already exist
imagename=datstr+solar_time+'_'+str(freq)+"MHz"
image_fold = 'images/'

# Create frequency folder, if it doesn't exist
freq_fold=str(freq)+"MHz"
if not os.path.isdir(freq_fold):
os.mkdir(freq_fold)

# Copy the solar data for this time (will be deleted later)
print('Copying solar data to frequency folder')
os.system("cp -r "+os.path.join(datapath,solar_ms)+"* "+freq_fold+"/")
# Copy the calibration data (will be deleted later)
print('Copying calibration data to frequency folder')
os.system("cp -r "+os.path.join(datapath,calib_ms)+"* "+freq_fold+"/")

os.chdir(freq_fold)
if not os.path.isdir(image_fold):
os.mkdir(image_fold)
if not os.path.isfile(bcal):
bcal = None
if not os.path.isdir('caltables'):
os.mkdir('caltables')

try:
solar_pipeline.image_ms(solar_ms=solar_ms,calib_ms=calib_ms,bcal=bcal,\
imagename=imagename,do_final_imaging=False,logfile='analysis_'+str(freq)+'.log')
msname = datstr+solar_time+'_'+str(freq)+'MHz_final.ms'
os.system("mv *calibrated_selfcalibrated_sun_only_sun_selfcalibrated_sun_only.ms final_ms/"+msname)
os.system("rm -rf *.ms* *.fits *.gcal *.cl *.badants")
# Make 10 images for this band (integrates over 19 or 20 subchannels, bandwidth ~0.4545 MHz)
os.system('wsclean -no-dirty -size 1024 1024 -scale 1arcmin -weight uniform -minuv-l 10 -name '+imagename+' -niter 10000 -mgain 0.8 -beam-fitting-size 1 -pol I -join-channels -channels-out 10 final_ms/'+msname)
# Convert images to heliocentric, move them to the final image folder, and delete all fits files
files = glob.glob('*-image.fits')
for imgfile in files:
solar_pipeline.correct_primary_beam('final_ms/'+msname, imgfile.split('-image.fits')[0])
helio_image = utils.convert_to_heliocentric_coords('final_ms/'+msname, imgfile)
os.system('mv '+helio_image+' '+image_fold)
os.system('rm *.fits')
except:
pass
os.chdir(home)

</pre>
== What Happens When You Run the Script ==
One way to run this script is to cut-and-paste into a file, say process.py, and then in an iPython session type
<pre>
import sys
sys.path.append('/home/dgary/ovro-lwa-solar') # Change to your path
run 'process.py'
</pre>
If all goes well, after many hours you will have all of your images. If you examine the script, you will see that there are two loops, an inner one over frequency and an outer one over time. The inner loop will create a subdirectory for the frequency it is working on (first will be subdirectory named 27MHz), then do the calibration for that frequency and create a subfolder caltables with a .bcal file in it. Luckily, this only has to be done once and then the .bcal file will be used for subsequent times so its creation will be skipped. Other files with .gcal extension will be created for the first data time, and also will be reused for subesquent times up to one hour later. When a new .gcal file is needed, the pipeline will create it automatically for you. The gain files take about 10 min for each frequency, but again is only done once for an hour of data. After the calibration is complete, <code>wsclean</code> is used to create images (in 10 subbands of each 4.5 GHz band, plus an MFS image integrated over the whole band). They are converted to heliographic coordinates and you will find them in 27MHz/images when done. This takes another 10 minutes or so.

When all of that is done for the first frequency, the whole process starts again for the next, and so one until all images for the first time are done. In this example, then, it will take about 20/min per frequency * 13 frequencies = 260 minutes (> 4 hours!) to make all 143 images for the first time (10 images per band + 1 MFS image). For subsequent times, though, the calibration step is skipped so each subsequent time will take 10 min * 13 frequencies (around 2 hours). That means the entire script will run in about 8 hours and produce 429 images.

Tohban OVRO-LWA Imaging Tutorial

2023-11-09T16:14:40Z

Dgary: /* Calibration and Imaging Script */

=Initial Setup=
The OVRO-LWA has three solar modes that can operate concurrently. These are (1) the beamformer, which creates a high-resolution spectrogram of the solar activity each day, (2) a slow visibility mode that records data in CASA ms format for all 352 antennas and all 3072 frequencies at 10-s cadence, and (3) a fast visibility mode that records data for a 48-antenna subset (generally the outer antennas) and 768 frequencies at 1-s cadence. The recorders that record the data are all activated separately, so it is not guaranteed that data from all three modes are available at any one time. Also, because of the vast data volume most of the recorded data are not saved, but rather are overwritten after a day or so, hence any data that are wanted must be explicitly saved by copying it to another location. Again because of the large volume of data, such copying is too slow to save much data (at least at present), so we can generally save only about an hour of data per day.

'''Note: This tutorial only describes how to work with the slow visibility data at the moment.'''

==Python Environment==
The imaging pipeline is written in Python 3, so in order to use it one must set up a Python 3 environment. These instructions assume you are working in your own home directory on the Pipeline machine at OVRO. First enter the bash shell if you are not already in it. Type <code>echo $0</code> to see what shell you are in. If that returns something other than -bash, type <code>bash</code> to enter the shell. Next check if you have the line <code>alias loadpyenv3.8='source /home/user/.setenv_pyenv38'</code> in your ~/.bash_aliases file. If not, add it using your favorite editor, then activate it with <code>source ~/.bash_aliases</code>. From there, you can type <code>loadpyenv3.8</code> to enter the Python 3.8 environment. Finally, from your home folder, type <code> git clone https://github.com/binchensun/ovro-lwa-solar </code> to install the OVRO-LWA code. To test your Python environment, log out and log in again fresh, then type
<pre>
$> loadpyenv3.8
$> ipython --pylab
import sys
sys.path.append('/home/dgary/ovro-lwa-solar') # Replace with your own home directory
import solar_pipeline
</pre>
If that succeeds, you should be ready to proceed.

==Where to Find Data==
The next step is to find the data you want to work with. You will need some calibration data as well as the solar data for your target date. As of this writing, the existing solar data on Pipeline, is in two separate places: /nas5/ovro-lwa-data (data up to 2023-09-03) and /nas6/ovro-lwa-data (data from 2023-09-18 and later). All of the existing beamformed data (spectrograms) are in /nas5/ovro-lwa-data/beam/beam-data.

'''This tutorial uses the example of the type II burst on 2023-07-28.'''

==Examining the Spectrogram for Your Date==
It is good practice to examine the spectrogram for your date/time, to guide your selection of frequencies and times to use for imaging. You can check the folders and subfolders in /nas5/ovro-lwa-data/beam/beam-data to see what files exist. Note that the filenames have the Modified Julian Data (mjd) followed by hours, minutes, seconds in the format <mjdday>.<hh><mm><ss>?????????? where the ? indicate more digits of the fraction of a second. The type II burst we are interested in started around 15:43 UT on 2023 July 28, which is MJD 060154, so the file we want is <code>/nas5/ovro-lwa-data/beam/beam-data/202307/beam20230728/060153_152717110834334d2be</code>, which starts at 15:27:17 UT. Generally these files contain 30 min of data. The type II continues into the next file, which is <code>060153_1558172229518804396</code>.

To read and display this file, in iPython type
[[File:20230728-type-II.png|300px|left|'''2023 July 28 Type II event spectrogram''']] <pre>
import sys # If not already loaded
sys.path.append('/nas5/ovro-lwa-data/beam/software/')
from lwa import lwa_read, lwa_plot
datadir = '/nas5/ovro-lwa-data/beam/beam-data/202307/beam20230728/'
data = lwa_read(datadir+'060153_152717110834334d2be', stokes='IV', timebin=1, freqbin=4)
lwa_plot(data, vmax=15000,vmin=10)
</pre>
which defaults to log-scaled amplitudes and viridis color table for stokes I and linear-scaled amplitudes and grayscale for stokes V, as shown at left. You can examine lwa_plot? for more options. 
 
 

==Calibration and Imaging Script==
The script below assumes some previous setup. First, a "home" directory needs to be created and the script must be run from that directory. Because of the large amount of disk space required, create your "home" directory on /data1. Mine is /data1/dgary/OVRO-LWA/20230728_workdir. Before running the script, you'll need to change the 7 lines indicated with the '''***Change''' comments.
# The first such line is the list of frequency bands you want to image. In this case I have all 13 useful bands. Frequencies below 27 MHz rarely image well and in many cases we did not save the data for those frequencies anyway.
# The second is a string representing the date of the event, including an underscore (this is part of a filename).
# The third line is a list of solar times. These times have to exactly match existing filenames, so you'll have to do a listing of the data directory to check them. ''Warning: Doing a listing of the entire data directory is time consuming and not useful, since there are many thousands of files there.'' Instead, use something like: <code>ls /nas5/ovro-lwa-data/20230728/slow/20230728_1553*</code> to limit the number of files returned.
# The fourth line is the date string of the calibration data. This will almost always be the same as the date string of the data, but it is possible to use a calibration from a different date if not too far apart.
# The fifth line is the time of the calibration data. Again, this must exist. Usually the calibration is done at night so the time will be quite different, e.g. 0500 UT, and a command like <code>ls /nas5/ovro-lwa-data/20230728/slow | head -20</code> will list the first 20 files in the folder, which are likely the calibration files. Unfortunately, no nighttime calibration exists for this date, so I had to use a daytime time, 15:40 UT.
# The sixth line is the path to the data.
# The seventh line is the path to the calibration data, again usually the same as that for the data.
<pre>
import os, glob
import utils
from time import time
import solar_pipeline

freqs=[27,32,36,41,46,50,55,59,64,69,73,78,82] # ***Change to the bands you want to image
datstr = '20230728_' # ***Change to the date of your event
solar_times = ['155306','155316','155326'] # ***Change to the times to use for solar imaging -- these times must exist!
caldatstr = '20230728_' # ***Change to the date of your cal data
cal_time = '154003' # ***Change to the time for your calibration
datapath = '/nas5/ovro-lwa-data/20230728/slow/' # ***Change to path to your data
calpath = '/nas5/ovro-lwa-data/20230728/slow/' # ***Change to path to your calibration data

home=os.getcwd()
for solar_time in solar_times:
for freq in freqs:
calib_ms=caldatstr+cal_time+'_'+str(freq)+"MHz.ms" # Will be copied from calpath
solar_ms=datstr+solar_time+'_'+str(freq)+"MHz.ms" # Will be copied from datapath
bcal='caltables/'+calib_ms.replace('ms','bcal') # Will be created if it doesn't already exist
imagename=datstr+solar_time+'_'+str(freq)+"MHz"
image_fold = 'images/'

# Create frequency folder, if it doesn't exist
freq_fold=str(freq)+"MHz"
if not os.path.isdir(freq_fold):
os.mkdir(freq_fold)

# Copy the solar data for this time (will be deleted later)
print('Copying solar data to frequency folder')
os.system("cp -r "+os.path.join(datapath,solar_ms)+"* "+freq_fold+"/")
# Copy the calibration data (will be deleted later)
print('Copying calibration data to frequency folder')
os.system("cp -r "+os.path.join(datapath,calib_ms)+"* "+freq_fold+"/")

os.chdir(freq_fold)
if not os.path.isdir(image_fold):
os.mkdir(image_fold)
if not os.path.isfile(bcal):
bcal = None
if not os.path.isdir('caltables'):
os.mkdir('caltables')

try:
solar_pipeline.image_ms(solar_ms=solar_ms,calib_ms=calib_ms,bcal=bcal,\
imagename=imagename,do_final_imaging=False,logfile='analysis_'+str(freq)+'.log')
msname = datstr+solar_time+'_'+str(freq)+'MHz_final.ms'
os.system("mv *calibrated_selfcalibrated_sun_only_sun_selfcalibrated_sun_only.ms final_ms/"+msname)
os.system("rm -rf *.ms* *.fits *.gcal *.cl *.badants")
# Make 10 images for this band (integrates over 19 or 20 subchannels, bandwidth ~0.4545 MHz)
os.system('wsclean -no-dirty -size 1024 1024 -scale 1arcmin -weight uniform -minuv-l 10 -name '+imagename+' -niter 10000 -mgain 0.8 -beam-fitting-size 1 -pol I -join-channels -channels-out 10 final_ms/'+msname)
# Convert images to heliocentric, move them to the final image folder, and delete all fits files
files = glob.glob('*-image.fits')
for imgfile in files:
solar_pipeline.correct_primary_beam('final_ms/'+msname, imgfile.split('-image.fits')[0])
helio_image = utils.convert_to_heliocentric_coords('final_ms/'+msname, imgfile)
os.system('mv '+helio_image+' '+image_fold)
os.system('rm *.fits')
except:
pass
os.chdir(home)

</pre>
== What Happens When You Run the Script ==

Tohban OVRO-LWA Imaging Tutorial

2023-11-09T15:41:07Z

Dgary: /* Calibration and Imaging Script */

Tohban OVRO-LWA Imaging Tutorial

2023-11-09T15:25:43Z

Dgary: /* Examining the Spectrogram for Your Date */

Tohban OVRO-LWA Imaging Tutorial

2023-11-09T15:24:53Z

Dgary: /* Calibration and Imaging Script */

Tohban OVRO-LWA Imaging Tutorial

2023-11-09T14:51:59Z

Dgary: /* Examining the Spectrogram for Your Date */

Tohban OVRO-LWA Imaging Tutorial

2023-11-09T14:49:31Z

Dgary: /* Examining the Spectrogram for Your Date */

File:20230728-type-II.png

2023-11-09T14:48:27Z

Dgary: