[daip] [!8668]: AIPS - Reducing geodetic data and applying it to science data

[NRAO Helpdesk]

Amy Mioduszewski updated #8668
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       Staff (Owner): Amy Mioduszewski (was: -- Unassigned --)

Reducing geodetic data and applying it to science data
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           Ticket ID: 8668
                 URL: https://help.nrao.edu/staff/index.php?/Tickets/Ticket/View/8668
           Full Name: Alexandra Truebenbach
               Email: alexandra.truebenbach at colorado.edu
             Creator: User
          Department: AIPS Data Reduction
       Staff (Owner): Amy Mioduszewski
                Type: Issue
              Status: Open
            Priority: Default
                 SLA: NRAO E2E
      Template Group: Default
             Created: 12 July 2016 08:15 PM
             Updated: 12 July 2016 08:15 PM
                 Due: 15 July 2016 11:39 PM (2d 0h 0m)
      Resolution Due: 20 July 2016 08:15 PM (6d 20h 35m)


Hi all,

I'm in the process of reducing my geodetic data that I took along with my science data in improve astrometry.  My observations were long enough that I chose to do two geodetic blocks, at the beginning and end of my science observations.  However, now I'm not sure how to proceed when reducing these two blocks and then applying them to my science data.  As expected, I'm finding that atmospheric conditions are different during my beginning and end geodetic blocks.  Specifically, when I find instrumental phase corrections and do a 1st run of fringe using VLBAMPCL, if I use a scan from the first geodetic block, then there are still significant phase jumps between IFs in the 2nd block.  If I then go on to determine the MBDs using the corrections from VLBAMPCL, the MBDs are all < 1 ns for the first block but all ~4 ns for the second block.

Based on all this, my overall question is what is the standard procedure for applying multiple geodetic blocks to data?  From what I described above it looks like the MBDs need to be calculated separately for each block.  Then is it standard to interpolate between the MBDs for the two blocks and apply the interpolated results to the data?  If that is what's done, how does one go about doing it?

Thanks!
Alex Truebenbach

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