TWHydraBand7 Calibration for CASA 3.3

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Observing Log and Priors

External info
# In CASA
data=['X3c1.ms','X5d8.ms','X7ef.ms']
for vis in data:
  listobs(vis=vis,verbose=F)

Below we copy select parts of the listobs output reported in the CASA logger for reference.

X3c1.ms:
Data records: 278352       Total integration time = 6109.06 seconds
   Observed from   22-Apr-2011/00:01:52.9   to   22-Apr-2011/01:43:42.0 (UTC)

X5d8.ms:
Data records: 278406       Total integration time = 5995.01 seconds
   Observed from   22-Apr-2011/01:48:05.8   to   22-Apr-2011/03:28:00.8 (UTC)

X7ef.ms:
Data records: 255717       Total integration time = 5407.49 seconds
   Observed from   22-Apr-2011/03:30:39.7   to   22-Apr-2011/05:00:47.2 (UTC)

  ID   Code Name         RA            Decl           Epoch   SrcId 
  0    none 3c279        12:56:11.1666 -05.47.21.5247 J2000   0     
  1    none Titan        00:00:00.0000 +00.00.00.0000 J2000   1     
  2    none TW Hya       11:01:51.9063 -34.42.17.0212 J2000   2     
  3    none J1147-382=Q* 11:47:01.3815 -38.12.11.1179 J2000   3     
  4    none J1037-295=Q* 10:37:16.0899 -29.34.02.9888 J2000   4     

  SpwID  Chans Frame Ch1(MHz)    ChanWid(kHz)TotBW(kHz)  Ref(MHz)    Corrs   
  0           4 TOPO  184550      1500000     7500000     183300      I   
  1         128 TOPO  355740.062  15625       2000000     355732.25   XX  YY  
  2           1 TOPO  356716.625  1796875     1796875     355732.25   XX  YY  
  3         128 TOPO  356507.813  15625       2000000     356500      XX  YY  
  4           1 TOPO  357484.375  1796875     1796875     356500      XX  YY  
  5         128 TOPO  346792.187  15625       2000000     346800      XX  YY  
  6           1 TOPO  345784.375  1796875     1796875     346800      XX  YY  
  7         128 TOPO  345182.438  15625       2000000     345190.25   XX  YY  
  8           1 TOPO  344174.625  1796875     1796875     345190.25   XX  YY  
  9         128 TOPO  344386.763  15625       2000000     344394.575  XX  YY  
  10          1 TOPO  343378.95   1796875     1796875     344394.575  XX  YY  
  11        128 TOPO  346324.263  15625       2000000     346332.075  XX  YY  
  12          1 TOPO  345316.45   1796875     1796875     346332.075  XX  YY  
  13        128 TOPO  354402.388  15625       2000000     354394.575  XX  YY  
  14          1 TOPO  355378.95   1796875     1796875     354394.575  XX  YY  
  15        128 TOPO  356402.388  15625       2000000     356394.575  XX  YY  
  16          1 TOPO  357378.95   1796875     1796875     356394.575  XX  YY  
  17       3840 TOPO  356497.936  122.070312  468750      355732.25   XX  YY  
  18          1 TOPO  356732.189  468750      468750      355732.25   XX  YY  
  19       3840 TOPO  357734.314  122.070312  468750      356500      XX  YY  
  20          1 TOPO  357499.939  468750      468750      356500      XX  YY  
  21       3840 TOPO  346034.314  122.070312  468750      346800      XX  YY  
  22          1 TOPO  345799.939  468750      468750      346800      XX  YY  
  23       3840 TOPO  343955.936  122.070312  468750      345190.25   XX  YY  
  24          1 TOPO  344190.189  468750      468750      345190.25   XX  YY  

   ID=   0-3: 'DV04'='J505', 'DV06'='T704', 'DV07'='J510', 'DV08'='T703', 
   ID=   4-7: 'DV09'='N602', 'DV10'='N606', 'PM01'='T702', 'PM02'='T701', 
   ID=   8-8: 'PM03'='J504'


Examine Tsys and WVR Tables, Apply, and Split

# In CASA
FDM=[17,19,21,23]
FDMtables=['X3c1.tsys.fdm','X5d8.tsys.fdm','X7ef.tsys.fdm']
plotrange=[0,0,50,500]
antennas='1,2,3,4,5,6,7,8]
for caltable in FDMtables:
  for spw in FDM:
   plotcal(caltable=caltable,xaxis='freq',yaxis='amp',
        iteration='antenna',subplot=421,poln='',spw='%d'%spw,antenna=antennas,
        showgui=F,figfile='FDM%d_%s.png'%(spw,caltable),fontsize=8.0,
        plotrange=plotrange)


# In CASA
data=['X3c1.ms','X5d8.ms','X7ef.ms']
fdm='17,19,21,23'
sources=['0','1','2','4']
nocal='3' # This source had no Tsys measurements associated with it

For sources with Tsys measurements apply only to themselves

# In CASA
for vis in data:
  for field in sources:
    applycal(vis=vis,spw=fdm,field=field,gainfield=field,
        gaintable=['%s.tsys.fdm'%(vis.split('.')[0]),'wvr_%s.cal'%(vis.split('.')[0])],
        interp=['nearest','nearest'],flagbackup=F)

For sources without Tsys, couple them with best source with Tsys

# In CASA
for vis in data:
  applycal(vis=vis,spw=fdm,field=nocal,
        gaintable=['%s.tsys.fdm'%(vis.split('.')[0]),'wvr_%s.cal'%(vis.split('.')[0])],
        gainfield=['4',nocal],interp=['nearest','nearest'],flagbackup=F)

Check Tsys application

# In CASA
plotms(vis='X5d8.ms',spw='17,19,21,23',xaxis='frequency',yaxis='amp',field='0,1',
       avgtime='1e8',avgscan=T,coloraxis='field',ydatacolumn='data')

spw 19 with atmospheric absorption gets a strange upward hitch probably from the interpolation from TDM

# In CASA
for vis in data:
  split(vis=vis,outputvis='%s_wvrtsys.ms'%(vis.split('.')[0]),datacolumn='corrected',spw=fdm)


Initial Inspection and Flagging

# In CASA
data=['X3c1_wvrtsys.ms','X5d8_wvrtsys.ms','X7ef_wvrtsys.ms']

for vis in data:
  flagdata(vis=vis,autocorr=True, flagbackup=T)
  flagdata(vis=vis,mode='shadow',diameter=12.0, flagbackup=F)
  flagdata(vis=vis,antenna='DV04', flagbackup=F)
# In CASA
plotms(vis='X3c1_wvrtsys.ms',spw='',xaxis='time',yaxis='amp',field='',avgchannel='3840',
       coloraxis='field',iteraxis='spw')
# In CASA
plotms(vis='X5d8_wvrtsys.ms',spw='',xaxis='time',yaxis='amp',field='',avgchannel='3840',
       coloraxis='field',iteraxis='spw')
# In CASA
plotms(vis='X7ef_wvrtsys.ms',spw='',xaxis='time',yaxis='amp',field='',avgchannel='3840',
       coloraxis='field',iteraxis='spw')
  1. In spw2 there are some low points. Locate suggests YY and
  2. PM03. Switch to coloraxis='corr'
# In CASA
plotms(vis='X3c1_wvrtsys.ms',spw='2',xaxis='time',yaxis='amp',field='',avgchannel='3840',
       coloraxis='corr')
  1. To further check remove PM03 from the plot.
# In CASA
plotms(vis='X3c1_wvrtsys.ms',spw='2',xaxis='time',yaxis='amp',field='',avgchannel='3840',
       coloraxis='corr',antenna='!PM03')
  1. Unzoom does not work, but flip to next page and back does.


# In CASA
data=['X3c1_wvrtsys.ms','X5d8_wvrtsys.ms','X7ef_wvrtsys.ms']

for vis in data:
  flagdata(vis=vis, flagbackup=T,
         spw=['2'],
         antenna=['PM03'],
         correlation=['YY'])
  1. Check phase / delay
# In CASA
plotms(vis='X3c1_wvrtsys.ms',spw='',xaxis='frequency',yaxis='phase',field='0',antenna='DV06',
       avgtime='1e8',avgscan=T,coloraxis='baseline',iteraxis='spw',xselfscale=T)
# In CASA
plotms(vis='X5d8_wvrtsys.ms',spw='',xaxis='frequency',yaxis='phase',field='0',antenna='DV06',
       avgtime='1e8',avgscan=T,coloraxis='baseline',iteraxis='spw',xselfscale=T)
# In CASA
plotms(vis='X7ef_wvrtsys.ms',spw='',xaxis='frequency',yaxis='phase',field='0',antenna='DV06',
       avgtime='1e8',avgscan=T,coloraxis='baseline',iteraxis='spw',xselfscale=T)
  1. Now look for birdies
  1. Titan and 3C279
# In CASA
plotms(vis='X3c1_wvrtsys.ms',spw='',xaxis='frequency',yaxis='amp',field='0,1',
       avgtime='1e8',avgscan=T,coloraxis='field',iteraxis='spw',xselfscale=T)
  1. TW Hydra and Phase cals
# In CASA
plotms(vis='X3c1_wvrtsys.ms',spw='',xaxis='frequency',yaxis='amp',field='2,3,4',
       avgtime='1e8',avgscan=T,coloraxis='field',iteraxis='spw',xselfscale=T,yselfscale=T)


  1. Quick check that other two datasets are the same
  1. Titan and 3C279
# In CASA
plotms(vis='X5d8_wvrtsys.ms',spw='',xaxis='frequency',yaxis='amp',field='0,1',
       avgtime='1e8',avgscan=T,coloraxis='field',iteraxis='spw',xselfscale=T)
# In CASA
plotms(vis='X7ef_wvrtsys.ms',spw='',xaxis='frequency',yaxis='amp',field='0,1',
       avgtime='1e8',avgscan=T,coloraxis='field',iteraxis='spw',xselfscale=T)
  1. TW Hydra and Phase cals
# In CASA
plotms(vis='X5d8_wvrtsys.ms',spw='',xaxis='frequency',yaxis='amp',field='2,3,4',
       avgtime='1e8',avgscan=T,coloraxis='field',iteraxis='spw',xselfscale=T,yselfscale=T)
  1. birdies seem weaker, some gone
# In CASA
plotms(vis='X7ef_wvrtsys.ms',spw='',xaxis='frequency',yaxis='amp',field='2,3,4',
       avgtime='1e8',avgscan=T,coloraxis='field',iteraxis='spw',xselfscale=T,yselfscale=T)
  1. Change to channel space to get channels for flagging
  1. TW Hydra and Phase cals
# In CASA
plotms(vis='X3c1_wvrtsys.ms',spw='',xaxis='channel',yaxis='amp',field='2,3,4',
       avgtime='1e8',avgscan=T,coloraxis='field',iteraxis='spw')


# In CASA
data=['X3c1_wvrtsys.ms','X5d8_wvrtsys.ms','X7ef_wvrtsys.ms']

for vis in data:
  flagdata(vis=vis, flagbackup=T,
         spw=['0:1067~1068;1279~1280;2367~2368;3775~3776',
              '1:1279~1280;2367~2368;3775~3776',
              '2:1279~1280;3775~3776',
              '3:831~832;1535~1536;2367~2368;3775~3776;3839~3839'])
  1. force reload and check that flagging has been done as anticipated.

Flag Calibrator Spectral Features

Set Up the Flux Calibrator Model

Bandpass

Gain Calibration

Applycal and Inspect