SWWOBBLER
Keywords: pako

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SWWOBBLER

        SWWOBBLER wOffset1 [wOffset2]

        Select and set up wobbler switching using the wobbling secondary
        mirror to switch between 2 positions on the sky.  This is typically
        used with the observing modes POINTING, FOCUS, ONOFF, or --with the
        bolometer-- OTFMAP.

        Real      :: wOffset1          ! 1st wobbler offset (1/2 "throw")
        Real      :: wOffset2          ! 2nd wobbler offset = -wOffset1

        IMPORTANT NOTE: Observers must inform the operator if they want to use
        this feature.

        There is a relation between the maximum allowed Wobbler throw and the
        minimum time per phase: for large throws the switching must be slow,
        i.e., time per phase must be large.  For /timePhase 1 [sec] or longer,
        any wobbler throw is allowed up to the maximum of 240 ["].

        Posssible combinations are, e. g.:

        wOffset1   throw  timePhase
           -22"      44"    0.25 sec
           -22"      44"    1.0  sec
          -120"     240"    1.0  sec
          -120"     240"    2.0  sec

        Note that for OTFMAPs with Wobbler switching, special restoration
        algorithms are needed to recover an image of the source brightness
        distribution. These are available, e. g., in the MOPSIC software.

        If SWWOBBLER and ONOFF are combined in the standard way, we
        effectively take data at 3 positions:

        1. the source position
        2. the source position + throw  (offset in the "true-angle" horizontal syste
        3. the source position - throw  (offset in the "true-angle" horizontal syste

        with throw = ABS(wOffset2-wOffset1).

        Data from 1. are treated as source signal, data from 2 and 3 as
        off-source reference signal.  Note that in the astronomical
        coordinates, positions 2 and 3 will rotate around the source position
        (1).  Therefore one must normally be sure that the extent of the source
        is less than throw-beamWidth (/2).

Subsections

- SWWOBBLER /DEFAULTS
- SWWOBBLER /TPHASE