[daip] [!13077]: AIPS - How to add random noise to the model data

[Eric Greisen]

Eric Greisen updated #13077
---------------------------

       Staff (Owner): Eric Greisen (was: -- Unassigned --)

How to add random noise to the model data
-----------------------------------------

           Ticket ID: 13077
                 URL: https://help.nrao.edu/staff/index.php?/Tickets/Ticket/View/13077
                Name: JongHo Park
       Email address: jhpark at astro.snu.ac.kr
             Creator: User
          Department: AIPS Data Reduction
       Staff (Owner): Eric Greisen
                Type: Issue
              Status: Open
            Priority: Default
                 SLA: NRAO E2E
      Template group: Default
             Created: 28 November 2018 07:11 PM
             Updated: 29 November 2018 03:17 PM
           Reply due: 02 December 2018 07:11 PM (3d 3h 54m)
      Resolution due: 24 August 2021 05:00 PM (999d 1h 43m)

UVMOD is the standard way to add random noise to visibilities.The noise in the output image depends on how much data youput into the image as well as the noise in each visibility.  TheSEFD of the VLA is a few 100 meaning the noise in 1 second in1 Hz bandwidth is a few 100 Jy.  Divide that by the sqrt (bandwidth in Hz * integration time in sec) to get an appropriate noise value.  Since FACTOR is likely to be 1.0 to keep the input model, the adverb FLUXis in Jy/sqrt(weight).You could use DTSIM to create your data set but it does not takea Clean model but it allows you to invent your antennas, observing strategy, etc.Eric Greisen


------------------------------------------------------
Staff CP:  https://help.nrao.edu/staff
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://listmgr.nrao.edu/pipermail/daip/attachments/20181129/286a9263/attachment-0001.html>