; PHAT
;---------------------------------------------------------------
;! Prussian hat size
;# ADVERB IMAGING
;-----------------------------------------------------------------------
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;;
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;-----------------------------------------------------------------------
;---------------------------------------------------------------
PHAT      LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC
----------------------------------------------------------------
PHAT
Type:  Adverb (Real scalar)
Use:   Specifies the amplitude of the delta function to be added to the
       center of the beam before picking CLEAN components (the Prussian
       Hat).  This was once believed to aid convergence but is now
       seldom used.
Null Value:  NONE  ( 0 => nothing added)
Tasks:
   APCLN.......Deconvolves images with CLEAN algorithm.
   APVC........Deconvolves images with van Cittert algorithm.
   IMAGR.......Wide-field and/or wide-frequency Cleaning / imaging
               task.
   SDCLN.......Deconvolves image by Clark and then "SDI" cleaning
               methods.
Procedures:
   LINIMAGE....Build image cube from multi-IF data set.
----------------------------------------------------------------