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SOLVE FLUX

      CLIC\SOLVE FLUX [NOREFERENCE] [BEST n] [REAL] [/RESET]

  *** THIS HELP HAS NOT BEEN UPDATED FOR THE NGRX ***

  Calculate the fluxes of the sources in the current index  or  the  antenna
  efficiencies  (Jansky to Kelvin) if the source flux is known.  The command
  can also be used to bootstrap source fluxes from a known source.

  It should be used before computing any amplitude calibration, on an  index
  covering  a  reasonably  short  time interval to avoid possible efficiency
  variations.

  The commands should be used in the following way:

    - The command SET FLUX is used to define the flux of one, or several  of
      the sources in the current index for which the flux is known. Frequen-
      cies and dates may be specified.

    - Then the command SOLVE FLUX will use the sources of  known  flux  (op-
      tionally  with  matching frequencies and dates) to determine the effi-
      ciencies for all antennas. SOLVE FLUX now gives the decorrelation fac-
      tor  relative  to the efficiencies logged in the scan headers (assumed
      to be the standard single-dish efficiencies).

    - SOLVE FLUX then uses these antenna efficiences to compute  the  fluxes
      of all other sources. IF the keyword "BEST n" is present, the n anten-
      nas giving the highest fluxes will be used for averaging (n  is  1  to
      the number of available antennas). Default is n=3.

    -  The  command SHOW FLUX will give the current flux list. The reference
      sources are listed with a "FIXED" keyword, while the fluxes determined
      by SOLVE FLUX are listed as "FREE".

    - SOLVE FLUX /RESET can be used to reset the flux list (i.e. remove from
      the list all sources whose flux is not fixed) before processing.

    - The command PRINT FLUX will create a procedure that may be used  later
      to reload these fluxes in CLIC, if needed.

    -  The command PRINT FLUX will create a procedure that may be used later
      to reload these fluxes in CLIC, if needed.

    - The command STORE FLUX will store the fluxes and efficiencies  in  the
      headers of the observations in the current index.

  If  no  reference sources are available, the keyword NOREFERENCE should be
  given, and the default efficiencies stored in the data header will be used
  (step 2 in the above list is bypassed).

  The  keyword  REAL forces SOLVE FLUX to use the real part of the visibili-
  ties instead of the amplitude  to  derive  the  antenna  efficiencies  and
  source fluxes. This is only for test purposes and must not be used without
  asking an expert.


Gildas manager 2011-04-01