[daip] [!7503]: AIPS - Odd Amplitude Pattern for MK Baselines

[Alexandra Truebenbach]

Alexandra Truebenbach updated #7503
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Odd Amplitude Pattern for MK Baselines
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           Ticket ID: 7503
                 URL: https://help.nrao.edu/staff/index.php?/Tickets/Ticket/View/7503
           Full Name: Alexandra Truebenbach
               Email: alexandra.truebenbach at colorado.edu
             Creator: User
          Department: AIPS Data Reduction
       Staff (Owner): -- Unassigned --
                Type: Issue
              Status: Open
            Priority: Default
                 SLA: NRAO E2E
      Template Group: Default
             Created: 28 October 2015 05:28 PM
             Updated: 28 October 2015 05:28 PM
                 Due: 30 October 2015 05:28 PM (2d 0h 0m)
      Resolution Due: 05 November 2015 05:28 PM (8d 0h 0m)



Hi all,

I've noticed a strange amplitude pattern in my data from BT131A1_1 for the MK antenna.  I've attached two screenshots of examples. It occurs at all baselines with MK, although the frequency at which it occurs varies between baselines.  The attached examples are for two calibrators, 3C454.3 and 0234+285, although I see the same pattern for other sources and at all other times.  I've been following the VLBA pipeline in the AIPS cookbook and the examples shown include ionospheric, EOP, sampler, and gain corrections.  The observations are in X-band.  It was also raining throughout the observations at MK, causing high system temperatures and gains.

Do you know what could be causing these patterns?  I'm using my observations for astrometry and thus am not concerned with obtaining a flux, so do you think these patterns can just be ignored?  Or is there a way to fix the amplitude?  I've very much like to keep the MK baselines since I'm aiming for high-precision astrometry.

Thank you,
Alex Truebenbach

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