[daip] [!4218]: aips - Calibration of VLA HI data with multiple IFs

[John Michael Cannon]

John Michael Cannon updated #4218
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Calibration of VLA HI data with multiple IFs
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           Ticket ID: 4218
                 URL: https://help.nrao.edu/staff/index.php?/Tickets/Ticket/View/4218
           Full Name: John Michael Cannon
               Email: jcannon at macalester.edu
             Creator: User
          Department: AIPS Data Processing
       Staff (Owner): -- Unassigned --
                Type: Issue
              Status: Open
            Priority: Default
                 SLA: ALMA E2E
      Template Group: Default
             Created: 09 January 2014 11:46 AM
             Updated: 09 January 2014 11:46 AM
                 Due: 13 January 2014 11:46 AM (4d 0h 0m)
      Resolution Due: 20 January 2014 11:46 AM (11d 0h 0m)



Hello, 

I am attempting to calibrate data from program AC781.  This particular dataset has the primary calibrator data written into IF 2.  I am puzzled as to why this is the case, since in all of the other datasets acquired for this program the primary calibrator data was written into IF 1, along with all of the other data.   The outputs of LISTR follow:

File = TOL1924     .UVDATA.   1 Vol = 1  Userid = 3002
Freq =  1.407152678 GHz   Ncor =  2   No. vis =    127010
Scan summary listing
 
Scan      Source      Qual  Calcode Sub         Timerange          FrqID   START VIS  END VIS
   1 1937-399        : 0000  A        1  0/15:54:45 -   0/16:00:15     1       1       3303
   2 TOL 1924-416    : 0000           1  0/16:01:45 -   0/16:39:45     1    3304      26331
   3 1937-399        : 0000  A        1  0/16:41:15 -   0/16:44:45     1   26332      28731
   4 TOL 1924-416    : 0000           1  0/16:46:15 -   0/17:24:15     1   28732      50944
   5 1937-399        : 0000  A        1  0/17:25:45 -   0/17:29:45     1   50945      53428
   6 TOL 1924-416    : 0000           1  0/17:31:15 -   0/18:08:45     1   53429      74354
   7 1937-399        : 0000  A        1  0/18:10:15 -   0/18:14:15     1   74355      76813
   8 TOL 1924-416    : 0000           1  0/18:15:45 -   0/18:53:15     1   76814      97743
   9 1937-399        : 0000  A        1  0/18:54:45 -   0/18:58:45     1   97744     100227
  10 TOL 1924-416    : 0000           1  0/19:00:15 -   0/19:38:15     1  100228     121431
  11 1937-399        : 0000  A        1  0/19:39:45 -   0/19:43:45     1  121432     124010
  12 0137+331        : 0000  A        1  0/19:48:15 -   0/19:52:45     2  124011     127010
 
Source summary
Velocity type = 'BARYCENT'    Definition = 'OPTICAL '
 
  ID Source           Qual  Calcode RA(2000.0)     Dec(2000.0)  No. vis
   1 1937-399        : 0000   A     19:37:16.2173 -39:58:01.553   15709
   2 TOL 1924-416    : 0000         19:27:58.2000 -41:34:32.000  108301
   3 0137+331        : 0000   A     01:37:41.2994  33:09:35.134    3000
 
  ID Source            Freq(GHz) Velocity(Km/s) Rest freq (GHz)
   1 1937-399             1.4072      2835.0000          1.4204
   2 TOL 1924-416         1.4072      2835.0000          1.4204
   3 0137+331             1.4072      2835.0000          1.4204
 
Frequency Table summary
FQID IF#      Freq(GHz)      BW(kHz)   Ch.Sep(kHz)  Sideband  Bandcode
   1   1       1.40715268    3125.0002     48.8281      1  VLA_L
   2   1       1.40696988    3125.0002     48.8281      1  VLA_L

This issue propagates through the calibration.  For example, the bandpass solution is only valid for the IF that contains the primary cal data.  I am unable to run CALIB on the phase cal (i.e., IF 1) as a result.  

Do workarounds for this issue exist?

Many thanks,
John







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