; PBPARM
;---------------------------------------------------------------
;! Primary beam parameters
;# Adverb IMAGING
;-----------------------------------------------------------------------
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;-----------------------------------------------------------------------
PBPARM    LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC
----------------------------------------------------------------
PBPARM
Type:  Adverb  (Real array, 7 elements)
Use: PBPARM provides a cutoff for the evaluation of a primary beam
     and optionally provides its parameters:

  PBPARM......Primary beam parameters:
              (1) Lowest beam value to believe: 0 -> often says to
                  ignore the primary beam.  When the beam is required,
                  the default cutoff is task dependent.
              (2) > 0 => Use beam parameters from PBPARM(3)-
                   PBPARM(7)
              (3-7)..For all wavelengths, the beam is described by the
                function:
                   1.0 + X*PBPARM(3)/(10**3) + X*X*PBPARM(4)/(10**7) +
                   X*X*X*PBPARM(5)/(10**10) + X*X*X*X*PBPARM(6)/(10**13)
                   X*X*X*X*X*PBPARM(7)/(10**16)
                where X is (distance from the pointing position in arc
                minutes times the frequency in GHz)**2.  For the VLA,
                these parms are, by default, given by Perley's fits:
                                    (3)    (4)     (5)
                      0.0738 GHz  -0.897  2.71   -0.242
                      0.3275      -0.935  3.23   -0.378
                      1.465       -1.343  6.579  -1.186
                      4.885       -1.372  6.940  -1.309
                      8.435       -1.306  6.253  -1.100
                     14.965       -1.305  6.155  -1.030
                     22.485       -1.417  7.332  -1.352
                     43.315       -1.321  6.185  -0.983
                The defaults for PBPARM(6) and (7) are zero.
Tasks:
  BOXES....Adds Clean boxes to BOXFILE around sources from a list.
           Corrects survey fluxes by beam to decide if they should be
           included.
  FACES....Makes images of catalog sources for initial calibration.
           Corrects survey fluxes by beam to decide if they should be
           included.
  FLATN....Re-grid multiple fields into one image incl sensitivity.
           Corrects mosaic'd images for beam.
  IMFIT....Fits Gaussians to portions of an image.  Corrects answers for
           beam.
  JMFIT....Fits Gaussians to portions of an image.  Corrects answers for
           beam.
  LTESS....Makes mosaic images by linear combination.  Corrects images
           for primary beam.
  MOMNT....Calculates images of moments along x-axis (vel, freq, ch).
           Cutoff levels are adjusted fro the beam.
  PATGN....Task to create a user specified test or primary-beam
           pattern.
  PBCOR....Task to apply or correct an image for a primary beam.
  SAD......Finds and fits Gaussians to portions of an image.  the
           answers are corrected by the beam if desired.
  SETFC....Makes a BOXFILE for input to IMAGR.  Corrects survey fluxes
           by beam to decide if they should be included.
  SPCOR....Task to correct an image for a primary beam and spectral
           index.
  SPIXR....Fits spectral indexes to each row of an image incl
           curvature.  Cutoff levels are adjusted fro beam.
  STESS....Task which finds sensitivity in mosaicing.  Images are
           corrected for primary beam.
  TVSAD....Finds and fits Gaussians to portions of an image with
           interaction.  Answers are corrected for beam.
  UTESS....Deconvolves images by maximizing emptiness.
  VTESS....Deconvolves sets of images by the Maximum Entropy Method.
  XMOM.....Fits one-dimensional moments to each row of an image.  Cutoff
           levels are adjusted fro the primary beam.
----------------------------------------------------------------

