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SOLVE FLUX

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

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

    It  should be used before computing any amplitude calibration, on an in-
    dex covering a reasonably short time interval to  avoid  possible  effi-
    ciency 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.
        Frequencies 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
        factor relative to the efficiencies logged in the scan headers  (as-
        sumed 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  an-
        tennas  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 deter-
        mined 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 process-
        ing.

      - SOLVE FLUX /OUTPUT file [NEW] will produce an output file  with  the
        results  printed  for  each  antenna.  Use keyword NEW to open a new
        file.

      - The command PRINT FLUX will create a procedure that may be used lat-
        er 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 with-
    out asking an expert.


Gildas manager 2024-04-19