[daip] [!8044]: AIPS - multiband delay problem

[Mark Reid]

Mark Reid updated #8044
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multiband delay problem
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           Ticket ID: 8044
                 URL: https://help.nrao.edu/staff/index.php?/Tickets/Ticket/View/8044
           Full Name: Mark Reid
               Email: reid at cfa.harvard.edu
             Creator: User
          Department: AIPS Data Reduction
       Staff (Owner): -- Unassigned --
                Type: Issue
              Status: Open
            Priority: Default
                 SLA: NRAO E2E
      Template Group: Default
             Created: 15 February 2016 02:56 PM
             Updated: 15 February 2016 02:56 PM
                 Due: 17 February 2016 02:56 PM (2d 0h 0m)
      Resolution Due: 23 February 2016 02:56 PM (8d 0h 0m)



I am analyzing the  BeSSeL Survey observation BR210E5 and have a new problem with FRING when analyzing the geodetic-like blocks (spread-frequency K-band observations of strong QSOs).   

I ran FRING to do a manual phase calibration, applied this to the data, and then ran FRING to get multi-band delays.   With aparm(5)=2, I get the following error message:

FRING2: Task FRING  (release of 31DEC15) begins
FRING2: UVGET: Using flag table version   1 to edit data
FRING2: Set integration time to  1.000000 seconds, hope that is ok
FRING2: Selecting, editing and calibrating the data
FRING2: No need to divide by flux densities in this task
FRING2: Determining solutions
FRING2: Writing SN table    2
FRING2: FREQUENCY INCREMENTS NOT ALL SAME SIGN IN GROUP
FRING2: YOU MAY NEED TASK FLOPM
FRING2: Purports to die of UNNATURAL causes

Here is a LISTR output of the frequency information, which all looks fine.
FQID IF#      Freq(GHz)      BW(kHz)   Ch.Sep(kHz)  Sideband  Bandcode
   1   1      23.52200000   16000.0010    500.0000      1
       2      23.53600000   16000.0010    500.0000      1
       3      23.57800000   16000.0010    500.0000      1
       4      23.64800000   16000.0010    500.0000      1
       5      23.73200000   16000.0010    500.0000      1
       6      23.83000000   16000.0010    500.0000      1
       7      23.97000000   16000.0010    500.0000      1
       8      23.99800000   16000.0010    500.0000      1

And a PRTAB of the FQ table:

PRTAB1: Task PRTAB  (release of 31DEC16) begins
 rglinux1  PRTAB(31DEC16)    505     12-FEB-2016  15:29:43    Page    1
2016JA27E5DG.GEODAT.   1  Disk= 1    FQ Table version   1
Title: AIPS UV DATA FILE FREQUENCY TABLE
Created by      FITLD on 12-FEB-2016 14:53:03
Last written by Obit  on 12-FEB-2016 15:16:59
Ncol 6  Nrow 1    Sort cols:
    Table has     1 keyword-value pairs:
   NO_IF    =            8
   Table format incompatable with FITS ASCII tables
 
COL. NO.       1            2              3             4            5          6
     ROW    FRQSEL    IF FREQ          CH WIDTH     TOTAL BAND    SIDEBAND    RXCODE
  NUMBER              HZ               HZ           HZ
       1       1              0.000    500000.00    16000000.0        1
       1               14000000.000    500000.00    16000000.0        1
       1               56000000.000    500000.00    16000000.0        1
       1              126000000.000    500000.00    16000000.0        1
       1              210000000.000    500000.00    16000000.0        1
       1              308000000.000    500000.00    16000000.0        1
       1              448000000.000    500000.00    16000000.0        1
       1              476000000.000    500000.00    16000000.0        1

I tried both the 31DEC15 and 31DEC16 version of AIPS and get the same problem.

If it helps, here is the archive data base (only 230 MBytes) and the archive key:  h9YJWJEu
VLBA_BR210E5_br210e5_BIN0_SRC0_0_160208T205529.idifits     observed Jan 27, 2016

We have analyzed literally hundreds of data sets like this and this is the first time I've seen such a problem.

Mark Reid

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