Difference between revisions of "EVLA high frequency spectral line tutorial - IRC+10216 - calibration"

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(Created page with "'''This guide is under development.''' =Getting the data= The data for this tutorial can be obtained by anonymous FTP from <tt>ftp://ftp.aoc.nrao.edu/staff/gvanmoor/community_d...")
 
Line 11: Line 11:
 
wget 'ftp://ftp.aoc.nrao.edu/staff/gvanmoor/community_day/*'
 
wget 'ftp://ftp.aoc.nrao.edu/staff/gvanmoor/community_day/*'
 
</source>
 
</source>
 +
 +
=Data Inspection=
 +
 +
{{listobs}} provides almost all relevant observational parameters such as correlator setup (frequencies, bandwidths, channel number and widths, polarization products), sources, scans, scan intents, and antenna locations.  The following command writes the listobs output to a file on disk.  You can review the output at any time using '''less''' from the casapy or UNIX command line.
 +
 +
<source lang="python">
 +
# In CASA
 +
vis='day2_TDEM0003_20s_full'
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listobs(vis=vis, verbose=True, listfile=vis+'.listobs.txt')
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</source>
 +
 +
Here is a subset of the listobs output.
 +
 +
<pre>
 +
Fields: 4
 +
  ID  Code Name                RA              Decl          Epoch  SrcId nVis
 +
  2    D    J0954+1743          09:54:56.82363 +17.43.31.2224 J2000  2    32726
 +
  3    NONE IRC+10216          09:47:57.38200 +13.16.40.6600 J2000  3    99540
 +
  5    F    J1229+0203          12:29:06.69973 +02.03.08.5982 J2000  5    5436
 +
  7    E    J1331+3030          13:31:08.28798 +30.30.32.9589 J2000  7    2736
 +
  (nVis = Total number of time/baseline visibilities per field)
 +
Spectral Windows:  (2 unique spectral windows and 1 unique polarization setups)
 +
  SpwID  #Chans Frame Ch1(MHz)    ChanWid(kHz)  TotBW(kHz)  Corrs
 +
  0          64 TOPO  36387.2295  125          8000        RR  RL  LR  LL
 +
  1          64 TOPO  36304.542  125          8000        RR  RL  LR  LL
 +
Sources: 10
 +
  ID  Name                SpwId RestFreq(MHz)  SysVel(km/s)
 +
  0    J1008+0730          0    0.03639232    -0.026
 +
  0    J1008+0730          1    0.03639232    -0.026
 +
  2    J0954+1743          0    0.03639232    -0.026
 +
  2    J0954+1743          1    0.03639232    -0.026
 +
  3    IRC+10216          0    0.03639232    -0.026
 +
  3    IRC+10216          1    0.03639232    -0.026
 +
  5    J1229+0203          0    0.03639232    -0.026
 +
  5    J1229+0203          1    0.03639232    -0.026
 +
  7    J1331+3030          0    0.03639232    -0.026
 +
  7    J1331+3030          1    0.03639232    -0.026
 +
Antennas: 19:
 +
  ID  Name  Station  Diam.    Long.        Lat.
 +
  0    ea01  W09      25.0 m  -107.37.25.2  +33.53.51.0
 +
  1    ea02  E02      25.0 m  -107.37.04.4  +33.54.01.1
 +
  2    ea03  E09      25.0 m  -107.36.45.1  +33.53.53.6
 +
  3    ea04  W01      25.0 m  -107.37.05.9  +33.54.00.5
 +
  4    ea05  W08      25.0 m  -107.37.21.6  +33.53.53.0
 +
  5    ea07  N06      25.0 m  -107.37.06.9  +33.54.10.3
 +
  6    ea08  N01      25.0 m  -107.37.06.0  +33.54.01.8
 +
  7    ea09  E06      25.0 m  -107.36.55.6  +33.53.57.7
 +
  8    ea12  E08      25.0 m  -107.36.48.9  +33.53.55.1
 +
  9    ea15  W06      25.0 m  -107.37.15.6  +33.53.56.4
 +
  10  ea19  W04      25.0 m  -107.37.10.8  +33.53.59.1
 +
  11  ea20  N05      25.0 m  -107.37.06.7  +33.54.08.0
 +
  12  ea21  E01      25.0 m  -107.37.05.7  +33.53.59.2
 +
  13  ea22  N04      25.0 m  -107.37.06.5  +33.54.06.1
 +
  14  ea23  E07      25.0 m  -107.36.52.4  +33.53.56.5
 +
  15  ea24  W05      25.0 m  -107.37.13.0  +33.53.57.8
 +
  16  ea25  N02      25.0 m  -107.37.06.2  +33.54.03.5
 +
  17  ea27  E03      25.0 m  -107.37.02.8  +33.54.00.5
 +
  18  ea28  N08      25.0 m  -107.37.07.5  +33.54.15.8
 +
</pre>
 +
 +
Note that the Rest Frequency and Systemic Velocity are wrong in the listobs log by a factor 10^6 and 1000, respectively, given the quoted units (MHz) and (km/s). This was due to a temporary error in the EVLA Observing Tool that has subsequently been fixed. Because the sky frequencies are correct, and we set the rest frequency explicitly later in the deconvolution stage, this does not present a problem for the data reductions.

Revision as of 11:20, 5 January 2012

This guide is under development.

Getting the data

The data for this tutorial can be obtained by anonymous FTP from ftp://ftp.aoc.nrao.edu/staff/gvanmoor/community_day/. Download all 4 files TAR in this directory.

For example,

# In UNIX
wget 'ftp://ftp.aoc.nrao.edu/staff/gvanmoor/community_day/*'

Data Inspection

listobs provides almost all relevant observational parameters such as correlator setup (frequencies, bandwidths, channel number and widths, polarization products), sources, scans, scan intents, and antenna locations. The following command writes the listobs output to a file on disk. You can review the output at any time using less from the casapy or UNIX command line.

# In CASA
vis='day2_TDEM0003_20s_full'
listobs(vis=vis, verbose=True, listfile=vis+'.listobs.txt')

Here is a subset of the listobs output.

Fields: 4
  ID   Code Name                RA              Decl          Epoch   SrcId nVis
  2    D    J0954+1743          09:54:56.82363 +17.43.31.2224 J2000   2     32726
  3    NONE IRC+10216           09:47:57.38200 +13.16.40.6600 J2000   3     99540
  5    F    J1229+0203          12:29:06.69973 +02.03.08.5982 J2000   5     5436
  7    E    J1331+3030          13:31:08.28798 +30.30.32.9589 J2000   7     2736
   (nVis = Total number of time/baseline visibilities per field)
Spectral Windows:  (2 unique spectral windows and 1 unique polarization setups)
  SpwID  #Chans Frame Ch1(MHz)    ChanWid(kHz)  TotBW(kHz)  Corrs
  0          64 TOPO  36387.2295  125           8000        RR  RL  LR  LL
  1          64 TOPO  36304.542   125           8000        RR  RL  LR  LL
Sources: 10
  ID   Name                SpwId RestFreq(MHz)  SysVel(km/s)
  0    J1008+0730          0     0.03639232     -0.026
  0    J1008+0730          1     0.03639232     -0.026
  2    J0954+1743          0     0.03639232     -0.026
  2    J0954+1743          1     0.03639232     -0.026
  3    IRC+10216           0     0.03639232     -0.026
  3    IRC+10216           1     0.03639232     -0.026
  5    J1229+0203          0     0.03639232     -0.026
  5    J1229+0203          1     0.03639232     -0.026
  7    J1331+3030          0     0.03639232     -0.026
  7    J1331+3030          1     0.03639232     -0.026
Antennas: 19:
  ID   Name  Station   Diam.    Long.         Lat.
  0    ea01  W09       25.0 m   -107.37.25.2  +33.53.51.0
  1    ea02  E02       25.0 m   -107.37.04.4  +33.54.01.1
  2    ea03  E09       25.0 m   -107.36.45.1  +33.53.53.6
  3    ea04  W01       25.0 m   -107.37.05.9  +33.54.00.5
  4    ea05  W08       25.0 m   -107.37.21.6  +33.53.53.0
  5    ea07  N06       25.0 m   -107.37.06.9  +33.54.10.3
  6    ea08  N01       25.0 m   -107.37.06.0  +33.54.01.8
  7    ea09  E06       25.0 m   -107.36.55.6  +33.53.57.7
  8    ea12  E08       25.0 m   -107.36.48.9  +33.53.55.1
  9    ea15  W06       25.0 m   -107.37.15.6  +33.53.56.4
  10   ea19  W04       25.0 m   -107.37.10.8  +33.53.59.1
  11   ea20  N05       25.0 m   -107.37.06.7  +33.54.08.0
  12   ea21  E01       25.0 m   -107.37.05.7  +33.53.59.2
  13   ea22  N04       25.0 m   -107.37.06.5  +33.54.06.1
  14   ea23  E07       25.0 m   -107.36.52.4  +33.53.56.5
  15   ea24  W05       25.0 m   -107.37.13.0  +33.53.57.8
  16   ea25  N02       25.0 m   -107.37.06.2  +33.54.03.5
  17   ea27  E03       25.0 m   -107.37.02.8  +33.54.00.5
  18   ea28  N08       25.0 m   -107.37.07.5  +33.54.15.8

Note that the Rest Frequency and Systemic Velocity are wrong in the listobs log by a factor 10^6 and 1000, respectively, given the quoted units (MHz) and (km/s). This was due to a temporary error in the EVLA Observing Tool that has subsequently been fixed. Because the sky frequencies are correct, and we set the rest frequency explicitly later in the deconvolution stage, this does not present a problem for the data reductions.