As of Mon Jul 15 11:25:44 2024

OOSUB: Task to subtract CLEAN components from a uv data base.


                                   (or, to divide observed visi-
                                   bility by model visibility)
INNAME                             Input UV file name (name)
INCLASS                            Input UV file name (class)
INSEQ             0.0     9999.0   Input UV file name (seq. #)
INDISK                             Input UV file disk unit #
CHANNEL          -1.0     9999.0   Spectral channel (0=>all)
                                   Use 0 for continuum
BIF               0.0     9999.0   First IF (0=>1)
EIF               0.0     9999.0   Highest IF (0=>BIF to last)
IN2NAME                            Cleaned map name (name)
IN2CLASS                           Cleaned map name (class)
IN2SEQ            0.0     9999.0   Cleaned map name (seq. #)
IN2DISK                            Cleaned map disk unit #
NMAPS             0.0     4096.0   No. maps to use for model.
INVERS            0.0    46655.0   CC file version #. 0 -> 1
OUTNAME                            Output UV file name (name)
OUTCLASS                           Output UV file name (class)
OUTSEQ           -1.0     9999.0   Output UV file name (seq. #)
OUTDISK                            Output UV file disk unit #.
BCOMP                              First CLEAN comp to sub.
                                   1 per field.
NCOMP                              Last CLEAN comp to sub.
                                   to use (0 => all)
FLUX                               Lowest CC component used.
CMETHOD                            Modeling method:
                                   'DFT','GRID','    '
CMODEL                             Model type: 'COMP','IMAG'
                                   (see HELP re images)
FACTOR                             Factor times CLEAN fluxes.
                                   0->1.0  Subtract
                                     -1.0  Add
OPCODE                             'DIV ' => divide visibility
                                     observation by model vis.
                                   'MODL' => replace visibility
                                     with model visibility
                                   'MODU' => replace visibility
                                     with model visibility and
                                     unflag all channels
                                   anything else => subtract
SMODEL                             Source model, 1=flux,2=x,3=y
                                   See HELP SMODEL for models.
BPARM                              Task enrichment parameters
                                   (1) Antenna diameter (m)
                                        0 -> no correction
                                   (2) Omit CC options
                                   (3) spectral index radius
                                        0 -> no correction
FQTOL                              Frequency tolerance in kHz
                                   (primary beam & spec index)
IN3NAME                            Spectral index image name
IN3CLASS                           Spectral index image class
IN3SEQ                             Spectral index image sequence
IN3DISK                            Spectral index image disk
IN4NAME                            Spectral curvature name
IN4CLASS                           Spectral curvature class
IN4SEQ                             Spectral curvature sequence
IN4DISK                            Spectral curvature disk
BADDISK                            Disks to avoid for scratch


Task:  Subtracts/divides a model from/into a uv data base.  The model
       may be a specific model, a set of CLEAN components files, or a
       set of images.  "CLEAN" models may be points, Gaussians or
       uniform, optically thin spheres.  The task can also replace the
       observed visibilities with the model values.
            Model images made with both values of IMAGR's DO3DIMAG
       option are handled correctly, as are multi-scale images.  Set
            OOSUB works only on single-source files.
            OOSUB differs from UVSUB in that it offers the
       frequency-dependent primary beam and spectral index options
       found in IMAGR.

       WARNING: If any part of the IN3NAME group or IN4NAME group of
       adverbs is specified, then the images so described will be used
       as spectral index and curvature images.  Use CLR3NAME and
       CLR4NAME if you do not wish to apply such images.

       NOTE: this task does NOT apply flagging or calibration tables
       to the input UV data.  Run SPLIT first if that operation is
       desired.  The task assumes that the model has been computed or
       corrected to apply at the specific frequency in the header,

       NOTE: this task will work on multi-source files (unlike UVSUB)
       but the file must contain data for only one source.  A single
       model will be applied to all data in the file, so a true
       multi-source file will be rendered defective.

       If the multi-facet and/or frequency-dependent options are
       invoked, OOSUB will attempt to apply all facet models to each
       frequency group (set by FQTOL).  If the maximum size of the
       pseudo-AP (set by verb SETMAXAP) is not large enough, then
       OOSUB will use multiple passes through the data applying some
       combination of facets and frequencies in each pass.  All facets
       but only N frequency groups is preferred, but all channels and
       some facets will be tried.  The fall-back case is one facet and
       some channels.  The amount of memory required by each facet
       model in gridded mode is more than 4 times the number of pixels
       in the image (even when Clean components are used).  Thus large
       model images will produce more acurate gridded modeling but can
       use up memory rapidly.

  INNAME.....Input UV file name (name).    Standard defaults.
  INCLASS....Input UV file name (class).   Standard defaults.
  INSEQ......Input UV file name (seq. #).  0 => highest.
  INDISK.....Disk drive # of input UV file.0 => any.
  CHANNEL....Frequency channel, 0 => all (use 0 for continuum)
             If > 0, then subtract/divide only this channel but copy
             all channels with the others unchanged.  NOTE WELL:
             EIF will be set to BIF if CHANNEL >= 1.
  BIF........First IF to process. 0=>1
  EIF........Highest IF to process 0=> do BIF to highest.
             Note: not all data sets will have IFs.  See note under
             CHANNEL directly above too.  If the IF axis precedes the
             FREQ axis in the header, then all IFs must be done if all
             spectral channels are to be done.
  IN2NAME....Model map name (name).      Standard defaults.
  IN2CLASS...Model map name (class).     Standard defaults.
  IN2SEQ.....Model map name (seq. #).    0 => highest.
  IN2DISK....Disk drive # of model map.  0 => any.
  NMAPS......Number of image files to use for model.  For multi-scale
             models, set NMAPS = NFIELD * NGAUSS to include the Clean
             components of the extended resolutions.  If more than one
             file is to be used, the NAME, CLASS, DISK and SEQ of the
             subsequent image files will be the same as the first file
             except that the LAST 3 or 4 characters of the CLASS will
             be an increasing sequence above that in IN2CLASS.  Thus,
             if INCLASS='ICL005', classes 'ICL005' through 'ICLnnn'
             or 'ICnnnn', where nnn = 5 + NMAPS - 1 will be used.  Old
             names (in which the 4'th character is not a number) are
             also supported: the last two characters are '01' through
             'E7' for fields 2 through 512.  In old names, the highest
             field number allowed is 512; in new names it is 4096.
  INVERS.....CC file version #.  You should specify this.  0 -> 1
  OUTNAME....Output UV file name (name).   Standard defaults.
  OUTCLASS...Output UV file name (class).  Standard defaults.
  OUTSEQ.....Output UV file name (seq. #). 0 => highest unique.
  OUTDISK....Disk drive # of output UV file.  0 => highest with
  BCOMP......The first clean component to process. One value is
             specified for each field used.
  NCOMP......Number of Clean components to use for the model, one
             value per field.  If all values are zero, then all
             components in all fields are used.  If any value is not
             zero, then abs(NCOMP(i)) (or fewer depending on FLUX and
             negativity) components are used for field i, even if
             NCOMP(i) is zero.  If any of the NCOMP is less than 0,
             then components are only used in each field i up to
             abs(NCOMP(i)), FLUX, or the first negative whichever
             comes first.  If abs(NCOMP(i)) is greater than the number
             of components in field i, the actual number is used.  For
                   NCOMP = -1,0
             says to use one component from field one unless it is
             negative or < FLUX and no components from any other
             field.  This would usually not be desirable.
                   NCOMP = -1000000
             says to use all components from each field up to the
             first negative in that field.
                   NCOMP = -200 100 23 0 300 5
             says to use no more than 200 components from field 1, 100
             from field 2, 23 from field 3, 300 from field 5, 5 from
             field 6 and none from any other field.  Fewer are used if
             a negative is encountered or the components go below
  FLUX.......Only components > FLUX in absolute value are used in the
  CMETHOD....This determines the method used to compute the
             model visibility values.
             'DFT' uses the direct Fourier transform, this
             method is the most accurate.
             'GRID' does a gridded-FFT interpolation model
             '    ' allows the program to use the fastest
             NOTE: data in any sort order may be used by the
             'DFT' method but only 'XY' sorted data may be used
             by the 'GRID' method.
             NOTE: CMETHOD='GRID' does not work correctly for RL
             and LR data; DO NOT USE CMETHOD='GRID' for RL, LR!
  CMODEL.....This indicates the type of input model; 'COMP' means that
             the input model consists of Clean components, 'IMAG'
             indicates that the input model consists of images.  If
             CMODEL is '   ' Clean components will be used if present
             and the image if not.  Note that Clean images do not make
             good models.  The Clean components have been convolved with
             the Gaussian Clean beam making their Fourier transform be
             rather tapered compared to the original uv data.
  FACTOR.....This value will be multiplied times the CLEAN component
             flux densities before subtraction.  The default 0->1.0, so
             the clean component model will be subtracted from the UV
             data.  FACTOR=-1 will add the clean component model to the
             UV data.  FACTOR will be adjusted by OOSUB for image
             models that are in JY/BEAM.  FACTOR is used with all
  OPCODE.....OPCODE='DIV ' => divide observed visibility by model
             OPCODE='MODL' => replace the visibility with the model
             OPCODE='MODU' => replace the visibility with the model
                visibility, set all weights to 1 undoing any channel
             Any other setting of OPCODE causes the task to subtract the
             model visibility from the observed visibility (the normal
             mode of operation).
  SMODEL.....A single component model to be used instead of a CLEAN
             components model; if abs (SMODEL) > 0 then use of this
             model is requested.
                SMODEL(1) = flux density (Jy)
                SMODEL(2) = X offset in sky (arcsec)
                SMODEL(3) = Y offset in sky (arcsec)
                SMODEL(4) = Model type:
                  0 => point model
                  1 => elliptical Gaussian and
                       SMODEL(5) = major axis size (arcsec)
                       SMODEL(6) = minor axis size (arcsec)
                       SMODEL(7) = P. A. of major axis (degrees)
                  2 => uniform sphere and
                       SMODEL(5) = radius (arcsec)
  BPARM......Correction control parameters (SEE EXPLAIN IMAGR):
             (1) If > 0 then make frequency dependent primary beam
               corrections assuming an antenna diameter of IMAGRPRM(1)
               meters.  Note that VLA and ATCA arrays (TELESCOPE
               header parameter) use the default primary beam
               parameters defined elsewhere in AIPS, while other
               antennas actually use IMAGRPRM(1) as the diameter of a
               "standard" telescope.  See FQTOL below also.
             (2) If BPARM(1) > 0, you may omit selected CCs from the
               operation based on position:
                  BPARM(2) <= 0  : Include all CCs
                            = 1  : Omit CCs within the main beam at
                                   all frequencies
                            = 2  : Omit CCs within the main beam at
                                   some frequncies
                            = 3  : Omit Ccs outside the main beam at
                                   some frequencies
                            = 4  : Omit CCs outside the main beam at
                                   all frequencies
             (3) 1 => use a spectral-index image represented in
               IN3NAME, IN3CLASS, IN3SEQ, IN3DISK below to correct the
               Clean component model for each channel.  IN4NAME et al
               will also be used as a curvature image iff IN3NAME are
               bparm(3)-0.5 is used as a radius in pixels over which
               the spectral index image is averaged.  When it is small
               (0 < BPARM(3) <~ 1), the spectral index is interpolated
               rather than averaged.  See FQTOL below as well.  When
               doing spectral index, the primary beam correction
               (BPARM(1)) costs very little extra.  This parameter is
               IMAGRPRM(17) in IMAGR.
  FQTOL......Frequency tolerance in kHz.  Spectral channels with FQTOL
             are handled together (use the same average CC model) when
             applying the primary beam and spectral index
             corrections.  Default is to do each channel separately
             which can take a long time.
  IN3NAME....Image name of spectral index image; no default.
  IN3CLASS...Image class of spectral index image; no default.
  IN3SEQ.....Image sequence of spectral index image; 0 -> highest.
  IN3DISK....Disk of spectral image image; 0 -> any.
  IN4NAME....Image name of spectral index curvature image; no default.
             Curvature images should be base 10 rather than base e -
             they differ by a factor of 2.3.  Also the reference
             frequency is 1.0 GHz.  These are changes done 2010-07-13.
  IN4CLASS...Image class of spectral index curvature image; no
  IN4SEQ.....Image sequence of spectral index curvature image;
             0 -> highest.
  IN4DISK....Disk of spectral curvature image image; 0 -> any.
  BADDISK....The disk numbers to avoid for scratch files.