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ONOFF

    ONOFF xOffset yOffset

    Specify on-off measurement, a.k.a. "position switching".

    Real      :: xOffset           ! x-offset of "on-source" position
    Real      :: yOffset           ! y-offset of "on-source" position

    Character :: sourceName        ! name of "on-source" position

    NOTE: if SWWOBBLER is the selected switching mode, the special option
    /SWWOBBLER YES (TRUE) is implied even without specifying it, and the
    on-off parameters appropriate for on-off Wobbler switching are set.


    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).


    /REFERENCE xOffsetR yOffsetR [systemNameRef]
    or
    /REFERENCE NO                  ! no reference

    position of off-source reference subscans

    Real      :: xOffsetR          ! x-offset
    Real      :: yOffsetR          ! y-offset
    Character :: systemNameRef     ! name of system
                                   ! see /SYSTEM for choices

    NOTE: with the usage /REFERENCE xOffsetR yOffsetR, both parameters are requi
    but you can replace either parameter with * to leave it unchanged.

    /SYSTEM systemName

    Name of system for offsets.

    Character :: systemName          ! name of system, one of:
                                     ! PROJECTION
                                     ! TRUEHORIZON
                                     ! NASMYTH

    <<TBD:                           ! DESCRIPTIVE>>
    <<TBD:                           ! BASIS>>
    <<TBD:                           ! EQUATORIAL>>
    <<TBD:                           ! HADECL>>
    <<TBD:                           ! HORIZONTAL>>

    PROJECTION for now means only the standard simple "radio" projection
    offsets in the chosen coordinate system. This is normally the
    astronomical system of offsets in which point-by-point (TRACK, ONOFF)
    or on-the-fly (OTFMAP) maps are made.

    TRUEHORIZON means the horizontal system with a factor 1/cos(elevation)
    applied to the azimuth offset.

    NASMYTH are special offsets to point an off-center pixel of a
    focal-plane array receiver (bolometer, HERA) to the commanded
    astronomical position, e.g., to use an off-center pixel for pointing,
    focus, ONOFF.

    IMPORTANT NOTE: projection, trueHorizon

       If the observing mode (LISSAJOUS, ONOFF, OTFMAP, ...)
       is in /SYSTEM projection,
       OFFSETS ... /SYSTEM projection is ignored (not used).
       If the observing mode (LISSAJOUS, ONOFF, OTFMAP, ...)
       is in /SYSTEM trueHorizon,
       OFFSETS ... /SYSTEM trueHorizon is ignored (not used).

    IMPORTANT NOTE: OFFSETS   /SYSTEM Nasmyth


       If OFFSETS xOffset yOffset /SYSTEM Nasmyth are specified in pako,
       the values xOffset yOffset are used during the observations.
       (this inludes the case that they are explicitly set to 0.0).
       It is up to the observer to make sure that they are "correct".
       (in pakoDisplay /SYS Nasmyth will be highlighted as yellow alert.)

       If OFFSETS xOffset yOffset /SYSTEM Nasmyth are not specified
       (cleared), for the MAMBO bolometer, Nasmyth offsets are used
       automatically according to the selected bolometer channel (pixel).


Subsections

Gildas manager 2023-06-01