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SET ATMOSPHERE

        CLIC\SET ATMOSPHERE Argument Value /ANTENNA a1 [a2 ...]

    Selects the way atmospheric calibration is done by  command  ATMOSPHERE,
    Argument may be FILE, AUTO, TREC, or MANUAL. This will affect the anten-
    nas given in argument to the option /ANTENNA (/ANTENNA ALL  selects  all
    antennas).  Argument  may  also be NEW, 2009, 2003, OLD, 1985, to switch
    between atmospheric model versions or INTERPOLATE to use tabulated atmo-
    spheric  model  (defined  to be GAG_ATMOSPHERE) ; option /ANTENNA is not
    required in that case.

      - In FILE mode the actual mode is taken from the data header,  as giv-
        en in the OBS program.

      -  In  TREC mode the receiver temperature is assumed known, to set the
        scale of measured sky temperature and optical depth,  and  determine
        the  system  noise  temperature.   The receiver temperature is taken
        from the data header, as given in OBS.  It may be forced to  a  dif-
        ferent  value by giving it as second argument 'value', or by the SET
        TREC command.

      - In AUTO mode the water wapor content is assumed  known;  it  is  de-
        termined   from   the  antennas  in TREC mode, if any, or taken from
        the data header, or forced  to  the  value  given   in   the  second
        argument 'value', or by the SET WATER command.

    These parameters, together with the wheather station data, are  used  to
    compute  the system noise temperature for each antenna.  In MANUAL mode,
    no model atmosphere is used,  but  the  values  of  optical  depths  and
    atmospheric temperatures stored in the data.

      - OLD or 1985 select the old ATM model, in use  at  IRAM  since  circa
        1985.

      - 2003 select the 2003 version of the ATM model,developed by Juan Par-
        do in ISM in Madrid. For this, the new ATM library  must  be  avail-
        able. If not the old ATM  will be used.

      -  NEW  or  2009  (the default) select the 2009 ATM model,developed by
        Juan Pardo in ISM in Madrid. For  this,  the  ATM  library  must  be
        available. If not the old ATM will be used.

      -  INTERPOLATE  will use a tabulated file produced by ASTRO\ATMOSPHERE
        MAKE. This option should not be used, as the use of  tabulated  file
        is only used to speed up calculations at Bure.


Gildas manager 2024-03-28