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UV_REF_POINT

        UV_REF_POINT  does  a Phase and/or Amplitude Referencing of a UV ta-
    ble, using another one representing a point source observed quasi-simul-
    taneously.  In details:

       - UV_REF_POINT self-calibrates first  the observed visibilities of the
         Gaussian  source used  as reference,  based  on the  knowledge of  the
         geometry and  flux of this  source.  The self-calibration  is baseline
         based (i.e. it does not take into account closure relationships).
       - UV_REF_POINT   then   applies   the   gains  derived   in   previous
         self-calibration to the visibilities of the source to be calibrated.

    It  is  STRONGLY ADVISED to self-calibrate the phase first, then the am-
    plitude using a longer smoothing time.  Moreover UV_REF_POINT enables to
    subtract (part of) the input reference source, typically to provide con-
    tinuum-free spectral line maps.

    See also UV_REF_GAUSS or UV_REF_MODEL, which does the  same  thing,  but
    using a Gaussian or modeled source as input.


Gildas manager 2014-07-01