[daip] [!10292]: AIPS - Using an existing clean map as the model in CALIB

[Alexandra Truebenbach]

Alexandra Truebenbach updated #10292
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Using an existing clean map as the model in CALIB
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           Ticket ID: 10292
                 URL: https://help.nrao.edu/staff/index.php?/Tickets/Ticket/View/10292
           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: 08 May 2017 10:55 PM
             Updated: 08 May 2017 10:55 PM
                 Due: 10 May 2017 10:55 PM (2d 0h 0m)
      Resolution Due: 16 May 2017 10:55 PM (8d 0h 0m)



Hi all,

I'm working on self-calibrating a set of observations taken with the VLBA but for one of the objects, the first run of CALIB fails on over 50% of the solutions (I assume a point source with an amplitude = previously measured flux density for this first run of CALIB). A plot of uv distance vs. amplitude shows that ~ 0.5 Jy of flux is detected so I should be able to successfully self-calibrate this object. Previous observations of this source show that the object has two lobes, which are both offset from the center of my observation. I'd like to try to use the previous observation's clean map as the initial model for my source in CALIB to help increase the initial success rate. However, the previous observation was taken in a different polarization and so when I use it as the source model, CALIB returns the error "MAP STOKES TYPE INCOMPATIBLE WITH UV DATA." I do not believe this source to be strongly polarized, so I'd like to use this clean map even though the stokes types don't match. Is there a way to get CALIB to ignore the stokes type or to trick it into thinking they're the same? 

Any other suggestions to help self-calibrate this object would also be great. I've tried giving CALIB a more complex gaussian initial model that better matches the previous observations, but this doesn't seem to help. 

Thanks! 
Alex Truebenbach

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