; GAIN
;---------------------------------------------------------------
;! specifies loop gain for deconvolutions
;# ADVERB IMAGING
;-----------------------------------------------------------------------
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;-----------------------------------------------------------------------
;---------------------------------------------------------------
GAIN      LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC
----------------------------------------------------------------
GAIN
Type: Adverb  (Real)
Use:  Loop gain for CLEAN.  This number will be multiplied by
      the peak in the residual map to determine the flux
      density of a CLEAN component to be removed.
Null value:  0
      Null value means take 0.10 as gain
Procedures:
   CXIMAGR.......Grid UV data into a complex image, Fourier transform,
                 Clean.
   DOFARS........Procedure to aid in Faraday rotation synthesis using the
                 FARS task.
   LINIMAGE......Build image cube from multi-IF data set.
   MAPPR.........Simplified access to IMAGR.
Tasks:
   APCLN.........Deconvolves images with CLEAN algorithm.
   APGS..........Deconvolves image with Gerchberg-Saxton algorithm.
   APVC..........Deconvolves images with van Cittert algorithm.
   BSCLN.........Hogbom Clean on beam-switched difference image.
   BSTST.........Graphical display of solutions to frequency-switched
                 data.
   CXCLN.........Complex Hogbom CLEAN.
   FARS..........Faraday rotation synthesis based on the brightness vs
                 wavelength.
   IMAGR.........Wide-field and/or wide-frequency Cleaning / imaging task.
   SAD...........Finds and fits Gaussians to portions of an image.  GAIN
                 is used in setting retry, cutoff, and warning levels.
   SCIMG.........Full-featured imaging plus self-calibration loop with
                 editing.
   SCMAP.........Imaging plus self-calibration loop with editing.
   SDCLN.........Deconvolves image by Clark and then "SDI" cleaning
                 methods.
   TARS..........Simulation of Faraday rotation synthesis (mainly task
                 FARS).
   TVSAD.........Finds and fits Gaussians to portions of an image with
                 interaction.  GAIN is used in setting retry, cutoff,
                 and warning levels.
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