MSETUP CALIBRATION
Keywords: mrtcal-user-manual

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MSETUP CALIBRATION

            [MRTCAL\]MSETUP CALIBRATION Keyword Switch

        [MRTCAL\]MSETUP CALIBRATION ANTSLOW_MJD_SHIFT Value

        Apply  (add)  a  shift in the antenna slow MJD traces of the given value
        (in seconds, can be positive or negative). As a result the antenna  will
        appear  earlier  or  later  at  the associated position (namely LONGOFF,
        LATOFF, CAZIMUTH, CELEVATI). The subscan start and stop  timestamps  are
        NOT shifted. The antenna fast traces are NOT shifted neither. Default is
        0, i.e. no shift is applied.

        [MRTCAL\]MSETUP CALIBRATION BAD YES|NO

        Choose if the bad time dumps in the BackendXXX tables  should  be  cali-
        brated  (in  addition  to  the  good  ones).  A bad time dump has a null
        ISWITCH value, and its associated data (e.g. MJD, INTEGTIM) are not  ex-
        pected to be correct. If YES is requested, you will likely be exposed to
        problems (e.g. if MJD column has incorrect values, searches in this col-
        umn may fail without advise). Default is NO.

        [MRTCAL\]MSETUP CALIBRATION BANDWIDTH Value

        Setup  the  desired calibration bandwidth in MHz. The nearest value that
        allows the division of the good spectra channels  of  each  chunkset  in
        equal virtual chunk sizes will be used. Exceptions are:
          - if value is 0, use the native hardware chunk size (no subdivision),
          - if  value  is larger than the native hardware chunk size, the latter
            is used instead (same as 0),
          - if value is lower than the channel spacing, the latter is  used  in-
            stead (all channels calibrated individually, use with caution).
        Default is 20 MHz.

        [MRTCAL\]MSETUP CALIBRATION CHOPPER STRICT|TOLERANT

        Setup  the chopper calibration engine. By default (strict mode), any er-
        ror occuring during this process (e.g. cold load greater than hot  load)
        blanks  the  resulting  data  at  the  chunk level (i.e. the surrounding
        chunks are calibrated if they have no problem). In  tolerant  mode,  the
        engine goes to the end of process, even if this implies non physical re-
        sults (e.g. negative Trec). This second mode is dangerous and should  be
        used for testing purposes only.
        In  both  modes,  a FLAG array is added to the calibration products (see
        HELP MSET OUTPUT CALIBRATION). It is 0 where no problem occured,  and  1
        otherwise.

        [MRTCAL\]MSETUP CALIBRATION FEEDBACK PIXEL|SET|ELEMENT

        Tune the granurality of the calibration results (Tsys, Tcal, Trec, ...).
        The median value per pixel, per chunkset, or per chunk element  will  be
        printed  in the PIXEL, SET, or ELEMENT mode, respectively. One value per
        chunk element may result in very long lists  when  using  virtual  chunk
        sizes (see MSETUP CALIBRATION BANDWIDTH). Default is SET.

        [MRTCAL\]MSETUP CALIBRATION INTERVAL ErrLimit [WarnLimit]

        Setup the time limits (in minutes) used when searching automatically for
        a calibration scan to be associated to a science scan. Beyond  ErrLimit,
        an  error  is  raised if no calibration scan is found. Beyond WarnLimit,
        only a warning is displayed. Automatic search is used  by  the  commands
        PIPELINE  and  CALIBRATE  without the option /WITH. The calibration scan
        always can be forced with CALIBRATE /WITH. Default ErrLimit is  30  min-
        utes, and WarnLimit defaults to 2/3 of ErrLimit.

        [MRTCAL\]MSETUP CALIBRATION MATCH Value

        Define  the  position matching tolerance when checking the subscan posi-
        tion(s) on sky. This tolerance is used 1) when checking that  a  'track'
        subscan  effectively  provides  dumps  at the same position, and 2) when
        grouping the subscans per ON or OFF positions, and  checking  that  each
        group effectively provides the same position. Default is 4 centi-arcsec-
        onds.

        [MRTCAL\]MSETUP CALIBRATION MJDINTER YES|NO

        Choose if Mrtcal should intersect the DATE-OBS  and  DATE-END  (on-track
        range)  of the subscans with the MJD columns in the tables Antenna Slow,
        Antenna Fast, and Backend Data. It may happen that one of these  columns
        are  too  short  and  the  data dumps can not be calibrated. Setting YES
        means that the associated dumps in this missing range won't  be  consid-
        ered on-track anymore, and won't be calibrated. Default is NO.

        [MRTCAL\]MSETUP CALIBRATION OFF NEAREST|LINEAR

        Define how to select the OFF subscan matching the current ON subscan da-
        ta (OTF PSW only). In NEAREST mode, the OFF subscan nearest in time will
        be used. In LINEAR mode, the algorithm will linearly interpolate between
        the two nearest OFF spectra. Default is LINEAR.

        [MRTCAL\]MSETUP CALIBRATION PRODUCTS LINEAR|NEAREST|SPLINE

        One set of calibration products Trec, Tcal, Tsys, precipitable water va-
        por,  and  zenithal  opacity is computed per chunk, at the middle of the
        chunk (chunk bandwidth is ruled by MSET  CALIB  BANDWIDTH).  In  NEAREST
        mode, the intermediate values on the frequency axis use the nearest com-
        puted values (flat value per chunk/bandwidth, possible discontinuities).
        In  LINEAR  mode,  the  intermediate values are interpolated between two
        middle of chunks (possible discontinuity of the derivatives). In  SPLINE
        mode,  the intermediate values are cubic spline interpolated between two
        middle of chunks (ensuring continuity of the first  and  second  deriva-
        tives). Default is LINEAR.

        [MRTCAL\]MSETUP CALIBRATION SCAN NEAREST|LINEAR

        Define  how  to select the calibration scan used calibrate science data.
        In NEAREST mode, the scan nearest in time will be used. In LINEAR  mode,
        the  algorithm  will linearly interpolate calibration parameters between
        the two nearest calibration scans. Default is NEAREST.

        [MRTCAL\]MSETUP CALIBRATION WATER SET
        [MRTCAL\]MSETUP CALIBRATION WATER ELEMENT
        [MRTCAL\]MSETUP CALIBRATION WATER FIXED Value

        Define if the precipitable water vapour amount should  be  minimized  or
        not:
          - SET means one single value for the whole bandwidth,
          - ELEMENT means one independent value per calibration bandwidth,
          - FIXED  Value  will  force  the pwv amount to the given value without
            minimization.
        Default is ELEMENT.