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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, 2003, OLD, 1985, to switch between
    atmospheric model versions; 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 (the default) select the old ATM model, in use at IRAM
        since circa 1985.

      - NEW or 2003 select the new ATM model,developed by Juan Pardo isf ISM
        in  Madrid.   For this the new ATM library must be available. If not
        the old ATM  will be used.


Gildas manager 2011-09-07