[daip] [!16519]: AIPS - Issues with UF002BC & UF002BD

[Eric Greisen]

Eric Greisen updated #16519
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       Staff (Owner): Eric Greisen (was: -- Unassigned --)
              Status: Open (was: Response Overdue)

Issues with UF002BC & UF002BD
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           Ticket ID: 16519
                 URL: https://help.nrao.edu/staff/index.php?/Tickets/Ticket/View/16519
                Name: Luis Fernandez
       Email address: lfernan at gmu.edu
             Creator: User
          Department: AIPS Data Reduction
       Staff (Owner): Eric Greisen
                Type: Issue
              Status: Open
            Priority: Default
                 SLA: NRAO E2E
      Template group: Default
             Created: 10 July 2020 07:50 AM
             Updated: 16 July 2020 10:57 AM
           Reply due: 20 July 2020 08:02 AM (3d 21h 4m)
      Resolution due: 11 April 2023 05:00 PM (999d 6h 2m)

Actually the drop is more like a factor of 5.  Since you use the same script on all runs, it is not likely to be the software itself.  You need to look at the data more closely.  In particular, the amplitude calibration depends mightily on the contents of the TY table.  They can be corrupted by lots of things esp RFI.   What are the fluxes you get for your calibration sources?  If they vary as much as the targets, then it is indeed the amplitude calibration.  If they are good then I would suspect phase calibration issues causing decorrelation of your targets.  Note, I consider the variation of flux in your plot between the 3 higher points as a lot - what is the uncertainty in each measured flux?
Eric Greisen


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