Flare Imaging - Revision history

Bchen: /* Self-calibration */

2019-05-15T14:01:17Z

Self-calibration

← Older revision		Revision as of 14:01, 15 May 2019
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	==Self-calibration==		==Self-calibration==
	As EOVSA does not calibrate as often as other general-purpose radio interferometers (e.g., VLA and ALMA), self-calibration is often needed in bringing out details of the flare at multiple frequencies. An example ~~CASA~~ script for doing self-calibration of the 2017 Aug 21 flare at ~20:20 UT can be found [https://github.com/binchensun/casa-eovsa/blob/master/slfcal_example.py at this Github link]. Here are some explanations on steps taken in this script.		As EOVSA does not calibrate as often as other general-purpose radio interferometers (e.g., VLA and ALMA), self-calibration is often needed in bringing out details of the flare at multiple frequencies. An example script, run in SunCASA, for doing self-calibration of the 2017 Aug 21 flare at ~20:20 UT can be found [https://github.com/binchensun/casa-eovsa/blob/master/slfcal_example.py at this Github link]. Here are some explanations on steps taken in this script.

	===Step 1: Preparation===		===Step 1: Preparation===

Bchen: /* Self-calibration */

2019-05-15T14:00:38Z

Self-calibration

@@ Line 25: / Line 25: @@
 ==Self-calibration==
-As EOVSA does not calibrate as often as other general-purpose radio interferometers (e.g., VLA and ALMA), self-calibration is often needed in bringing out details of the flare at multiple frequencies. An example CASA script for doing self-calibration of the 2017 Aug 21 flare at ~20:20 UT can be found [https://github.com/binchensun/casa-eovsa/blob/master/slfcal_20170821T2021.py at this Github link]
+As EOVSA does not calibrate as often as other general-purpose radio interferometers (e.g., VLA and ALMA), self-calibration is often needed in bringing out details of the flare at multiple frequencies. An example CASA script for doing self-calibration of the 2017 Aug 21 flare at ~20:20 UT can be found [https://github.com/binchensun/casa-eovsa/blob/master/slfcal_example.py at this Github link]. Here are some explanations on steps taken in this script.
 =[[DG Notes on 20170904 Event]]=

Bchen: /* Calibration */

2019-05-15T11:20:16Z

Calibration

← Older revision		Revision as of 11:20, 15 May 2019
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	Note for now there is an annoying issue in CASA 5.1.0 that clean does not run after any parallelized tasks. So it would be safe to <b>exit CASA before running calibeovsa if you set doimage=True</b>.		Note for now there is an annoying issue in CASA 5.1.0 that clean does not run after any parallelized tasks. So it would be safe to <b>exit CASA before running calibeovsa if you set doimage=True</b>.
	<pre>		<pre>
	calibeovsa(vis='~~IDB20170711201620_1~~.ms', caltype=['refpha','phacal'], doimage=True)		calibeovsa(vis='IDB20170821202020.ms', caltype=['refpha','phacal'], doimage=True)
	</pre>		</pre>
	This will calibrate the input visibility, write out calibration tables under /data1/eovsa/caltable/, and apply the calibration. If doimage=True, a quicklook image will be produced (by integrating over the entire time).		This will calibrate the input visibility, write out calibration tables under /data1/eovsa/caltable/, and apply the calibration. If doimage=True, a quicklook image will be produced (by integrating over the entire time).

Bchen: /* Calibration */

2019-05-15T11:20:02Z

Calibration

← Older revision		Revision as of 11:20, 15 May 2019
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	* Import Miriad file into CASA.		* Import Miriad file into CASA.
	<pre>		<pre>
	importeovsa(idbfiles='~~IDB20170711201620~~')		importeovsa(idbfiles='IDB20170821202020')
	</pre>		</pre>
	idbfiles could be a string of the IDB file name, or a list of IDB files. The output is automatically named "~~IDB20170711201620~~.ms".		idbfiles could be a string of the IDB file name, or a list of IDB files. The output is automatically named "IDB20170821202020.ms".

	* Perform reference phase calibration and multiband delay calibration (daily phase calibration). First, go to [http://ovsa.njit.edu/EOVSA/cal_status.php this page] and check if reference calibrations and daily phase calibrations have already been in the database. If not, create them following the instructions on [http://www.ovsa.njit.edu/wiki/index.php/Reference_Gain_Calibration reference calibration], [http://www.ovsa.njit.edu/wiki/index.php/Daily_Gain_Calibration daily phase calibration], and [http://www.ovsa.njit.edu/wiki/index.php/Total_Power_Calibration total power calibration].		* Perform reference phase calibration and multiband delay calibration (daily phase calibration). First, go to [http://ovsa.njit.edu/EOVSA/cal_status.php this page] and check if reference calibrations and daily phase calibrations have already been in the database. If not, create them following the instructions on [http://www.ovsa.njit.edu/wiki/index.php/Reference_Gain_Calibration reference calibration], [http://www.ovsa.njit.edu/wiki/index.php/Daily_Gain_Calibration daily phase calibration], and [http://www.ovsa.njit.edu/wiki/index.php/Total_Power_Calibration total power calibration].

Bchen: /* Preparation */

2019-05-15T11:19:44Z

Preparation

← Older revision		Revision as of 11:19, 15 May 2019
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	== Preparation ==		== Preparation ==
	First, identify the time when the flare in question happened. There are many ways to do this, but a nice way is to use the [http://sprg.ssl.berkeley.edu/~tohban/browser/ RHESSI Browser] and check "EOVSA Radio Data" on the upper left. Use the time you identified to find the corresponding IDB file(s) under /data1/eovsa/fits/IDB/yyyymmdd/. Then, on pipeline, it is advised to go to your working directory and <b>copy the IDB data into your directory</b>. Note, <b>never, NEVER, work directly on the IDB data in the original data directory!</b> Here I use /data1/eovsa/fits/IDB/~~20170711~~/~~IDB20170711201620~~ (2017 ~~July 11~~ C flare) as an example.		First, identify the time when the flare in question happened. There are many ways to do this, but a nice way is to use the [http://sprg.ssl.berkeley.edu/~tohban/browser/ RHESSI Browser] and check "EOVSA Radio Data" on the upper left. Use the time you identified to find the corresponding IDB file(s) under /data1/eovsa/fits/IDB/yyyymmdd/. Then, on pipeline, it is advised to go to your working directory and <b>copy the IDB data into your directory</b>. Note, <b>never, NEVER, work directly on the IDB data in the original data directory!</b> Here I use /data1/eovsa/fits/IDB/20170821/IDB20170821202020 (2017 Aug 21 C flare) as an example.

	== Calibration ==		== Calibration ==

Bchen: /* selfcalibration */

2019-05-15T11:18:37Z

selfcalibration

← Older revision		Revision as of 11:18, 15 May 2019
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	Note both importeovsa and calibeovsa are (customized) CASA tasks. If you want to use more functionality of them and/or see more information of each parameter, you can follow the normal procedure of [https://casa.nrao.edu/casadocs/casa-5.0.0/usingcasa/casa-tasks using a CASA task].		Note both importeovsa and calibeovsa are (customized) CASA tasks. If you want to use more functionality of them and/or see more information of each parameter, you can follow the normal procedure of [https://casa.nrao.edu/casadocs/casa-5.0.0/usingcasa/casa-tasks using a CASA task].

	==~~selfcalibration~~==		==Self-calibration==
	~~This section needs to~~ be ~~filled in~~.		As EOVSA does not calibrate as often as other general-purpose radio interferometers (e.g., VLA and ALMA), self-calibration is often needed in bringing out details of the flare at multiple frequencies. An example CASA script for doing self-calibration of the 2017 Aug 21 flare at ~20:20 UT can be found [https://github.com/binchensun/casa-eovsa/blob/master/slfcal_20170821T2021.py at this Github link]


	=[[DG Notes on 20170904 Event]]=		=[[DG Notes on 20170904 Event]]=

Bchen: /* Calibration */

2019-05-15T11:05:32Z

Calibration

← Older revision		Revision as of 11:05, 15 May 2019
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	casa		casa
	</pre>		</pre>


	* Import Miriad file into CASA.		* Import Miriad file into CASA.

Bchen: /* Calibration */

2019-05-15T11:05:26Z

Calibration

← Older revision		Revision as of 11:05, 15 May 2019
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	casa		casa
	</pre>		</pre>
	~~1. Perform polarization rotation and attenuation calibration.~~
	~~<pre>~~
	~~idbfile='IDB20170711201620'~~
	~~from eovsapy import pipeline_cal as pc~~
	~~pc.udb_corr(idbfile,calibrate=True)~~
	~~</pre>~~
	~~This will create a new IDB dataset named IDB20170711201620_1~~

	2. Import Miriad file into CASA.
			* Import Miriad file into CASA.
	<pre>		<pre>
	importeovsa(idbfiles='~~IDB20170711201620_1~~'~~, doscaling=False~~)		importeovsa(idbfiles='IDB20170711201620')
	</pre>		</pre>
	~~Remember it is important to set doscaling=False to disable scaling cross-correlation visibilities to auto-correlation~~. The output is automatically named "~~IDB20170711201620_1~~.ms".		idbfiles could be a string of the IDB file name, or a list of IDB files. The output is automatically named "IDB20170711201620.ms".

	3. Perform reference phase calibration and multiband delay calibration (daily phase calibration). First, go to [http://ovsa.njit.edu/EOVSA/cal_status.php this page] and check if reference calibrations and daily phase calibrations have already been in the database. If not, create them following the instructions on [http://www.ovsa.njit.edu/wiki/index.php/Reference_Gain_Calibration reference calibration], [http://www.ovsa.njit.edu/wiki/index.php/Daily_Gain_Calibration daily phase calibration], and [http://www.ovsa.njit.edu/wiki/index.php/Total_Power_Calibration total power calibration].		* Perform reference phase calibration and multiband delay calibration (daily phase calibration). First, go to [http://ovsa.njit.edu/EOVSA/cal_status.php this page] and check if reference calibrations and daily phase calibrations have already been in the database. If not, create them following the instructions on [http://www.ovsa.njit.edu/wiki/index.php/Reference_Gain_Calibration reference calibration], [http://www.ovsa.njit.edu/wiki/index.php/Daily_Gain_Calibration daily phase calibration], and [http://www.ovsa.njit.edu/wiki/index.php/Total_Power_Calibration total power calibration].

	Note for now there is an annoying issue in CASA 5.1.0 that clean does not run after any parallelized tasks. So it would be safe to <b>exit CASA before running calibeovsa if you set doimage=True</b>.		Note for now there is an annoying issue in CASA 5.1.0 that clean does not run after any parallelized tasks. So it would be safe to <b>exit CASA before running calibeovsa if you set doimage=True</b>.
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	calibeovsa(vis='IDB20170711201620_1.ms', caltype=['refpha','phacal'], doimage=True)		calibeovsa(vis='IDB20170711201620_1.ms', caltype=['refpha','phacal'], doimage=True)
	</pre>		</pre>
	This will calibrate the input visibility, write out calibration tables, and apply the calibration. If doimage=True, a quicklook image will be produced (by integrating over the entire time).		This will calibrate the input visibility, write out calibration tables under /data1/eovsa/caltable/, and apply the calibration. If doimage=True, a quicklook image will be produced (by integrating over the entire time).

	Note both importeovsa and calibeovsa are ~~now a~~ CASA ~~task~~. If you want to use more functionality of them and/or see more information of each parameter, you can follow the normal procedure of [https://casa.nrao.edu/casadocs/casa-5.0.0/usingcasa/casa-tasks using a CASA task].		Note both importeovsa and calibeovsa are (customized) CASA tasks. If you want to use more functionality of them and/or see more information of each parameter, you can follow the normal procedure of [https://casa.nrao.edu/casadocs/casa-5.0.0/usingcasa/casa-tasks using a CASA task].

	==selfcalibration==		==selfcalibration==

Dgary at 14:38, 5 November 2018

2018-11-05T14:38:44Z

← Older revision		Revision as of 14:38, 5 November 2018
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	==selfcalibration==		==selfcalibration==
			This section needs to be filled in.


			=[[DG Notes on 20170904 Event]]=

Bchen at 18:12, 25 October 2017

2017-10-25T18:12:10Z

← Older revision		Revision as of 18:12, 25 October 2017
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	Note for now there is an annoying issue in CASA 5.1.0 that clean does not run after any parallelized tasks. So it would be safe to <b>exit CASA before running calibeovsa if you set doimage=True</b>.		Note for now there is an annoying issue in CASA 5.1.0 that clean does not run after any parallelized tasks. So it would be safe to <b>exit CASA before running calibeovsa if you set doimage=True</b>.
	<pre>		<pre>
	calibeovsa(vis='IDB20170711201620_1.ms', caltype=['~~refcal~~','phacal'], doimage=True)		calibeovsa(vis='IDB20170711201620_1.ms', caltype=['refpha','phacal'], doimage=True)
	</pre>		</pre>
	This will calibrate the input visibility, write out calibration tables, and apply the calibration. If doimage=True, a quicklook image will be produced (by integrating over the entire time).		This will calibrate the input visibility, write out calibration tables, and apply the calibration. If doimage=True, a quicklook image will be produced (by integrating over the entire time).