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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 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.

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

      - 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 2018-11-19