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(Created page with "= Brief Instructions for Calibrating UDB Data = == Preparation == On pipeline, create a working directory in which the software will create any output, including the measureme...")
 
 
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cd /data1/dgary/solar/20170712_AR
cd /data1/dgary/solar/20170712_AR
</pre>
</pre>
Check if the UDB file you want already exists, in the appropriate subdirectory of /data1/eovsa/fits/UDBms. If so, you can skip the next section.
Check if the UDB file you want already exists, in the appropriate subdirectory of /data1/eovsa/fits/UDB. If so, you can skip the next section.


== Create a CASA UDBms file from a Miriad UDB file ==
== Create a CASA UDBms file from a Miriad UDB file ==
In CASA, check the inputs to the task '''importeovsa''':
In CASA, use task '''importeovsa''':
<pre>
<pre>
imp(importeovsa)
default(importeovsa)
</pre>
</pre>
and set the input idbfiles to the scan or scans you wish to work with, as in this example:
and set the input idbfiles to the scan or scans you wish to work with, as in this example:
<pre>
<pre>
idbfiles = '/data1/eovsa/fits/UDB/2017/UDB20170712183919'
idbfiles = '/data1/eovsa/fits/UDB/2017/UDB20170712183919'
</pre>
You can check the inputs by
<pre>
inp
</pre>
</pre>
You can change other inputs at this time, as desired, but the defaults are generally okay.  Then to execute, type
You can change other inputs at this time, as desired, but the defaults are generally okay.  Then to execute, type
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go
go
</pre>
</pre>
A single scan takes about 1 minute using one CPU.
A single scan takes about 1 minute using one CPU. The task will create a CASA measurement set under the current directory ended with "_scl.ms". In this case, it is "UDB20170712183919_scl.ms"


== Find and Apply the Reference Calibration ==
== Find and Apply the Reference Calibration ==
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tc.calibeovsa('/data1/dgary/solar/20170712_AR/UDB20170712183919_scl.ms',flagant='13~15')
tc.calibeovsa('/data1/dgary/solar/20170712_AR/UDB20170712183919_scl.ms',flagant='13~15')
</pre>
</pre>
This should produce a standard frequency-synthesis image with natural weighting, and also create a directory UDB20170712183919_scl.ms.flagversions.
This should perform reference phase calibration and daily phase calibration, and write several calibration tables to /data1/eovsa/caltable/yyyymm/. By default (with docalib=True), it will also calibrate the CASA measurement set by writing a "CORRECTED" data column to the dataset. Also, it produces a standard frequency-synthesis image in Band 6-8 with natural weighting averaging over the entire duration of the measurement set, and save the original CASA image and registered fits file in heliocentric coordinates under /data1/bchen/solar/image/yyyy/mm/dd/. In the meantime, it creates a directory UDB20170712183919_scl.ms.flagversions (in the current directory) which includes the flag information (one can always undo or redo the flag using task "flagmanager").

Latest revision as of 00:09, 23 July 2017

Brief Instructions for Calibrating UDB Data

Preparation

On pipeline, create a working directory in which the software will create any output, including the measurement set. Start CASA (takes a minute or so to load) and change to that directory

casa
cd /data1/dgary/solar/20170712_AR

Check if the UDB file you want already exists, in the appropriate subdirectory of /data1/eovsa/fits/UDB. If so, you can skip the next section.

Create a CASA UDBms file from a Miriad UDB file

In CASA, use task importeovsa:

default(importeovsa)

and set the input idbfiles to the scan or scans you wish to work with, as in this example:

idbfiles = '/data1/eovsa/fits/UDB/2017/UDB20170712183919'

You can check the inputs by

inp

You can change other inputs at this time, as desired, but the defaults are generally okay. Then to execute, type

go

A single scan takes about 1 minute using one CPU. The task will create a CASA measurement set under the current directory ended with "_scl.ms". In this case, it is "UDB20170712183919_scl.ms"

Find and Apply the Reference Calibration

At present, the task_calibeovsa script is not automatically loaded as a CASA task, so momentarily change to the appropriate folder and import the task, then change back to your desired folder:

cd /home/user/bchen/eovsa/suncasa/tasks/
import task_calibeovsa as tc
cd /data1/dgary/solar/20170712_AR
tc.calibeovsa('/data1/dgary/solar/20170712_AR/UDB20170712183919_scl.ms',flagant='13~15')

This should perform reference phase calibration and daily phase calibration, and write several calibration tables to /data1/eovsa/caltable/yyyymm/. By default (with docalib=True), it will also calibrate the CASA measurement set by writing a "CORRECTED" data column to the dataset. Also, it produces a standard frequency-synthesis image in Band 6-8 with natural weighting averaging over the entire duration of the measurement set, and save the original CASA image and registered fits file in heliocentric coordinates under /data1/bchen/solar/image/yyyy/mm/dd/. In the meantime, it creates a directory UDB20170712183919_scl.ms.flagversions (in the current directory) which includes the flag information (one can always undo or redo the flag using task "flagmanager").