AIPS HELP file for BSCLN in 31DEC24
As of Wed Apr 24 13:49:53 2024
BSCLN: Hogbom-like Clean on beam-switched difference image
INPUTS
INNAME Plus image name (name)
INCLASS Plus image name (class)
INSEQ 0.0 9999.0 Plus image name (seq. #)
INDISK 0.0 9.0 Plus image disk unit #
IN2NAME Minus image name (name)
IN2CLASS Minus image name (class)
IN2SEQ 0.0 9999.0 Minus image name (seq. #)
IN2DISK 0.0 9.0 Minus image disk unit #
OUTNAME Output image name (name)
OUTCLASS Output image name (class)
OUTSEQ -1.0 9999.0 Output image name (seq. #)
OUTDISK 0.0 9.0 Output image disk unit #.
BLC Bottom left corner of input
TRC Top right corner of input
DPARM (1) Throw corr factor
(2) Throw angle in degrees
(3) Plus/minus beam height
(4) Plus beam width corr.
(5) Minus beam width corr.
NITER Iterations
FLUX Min flux for component
GAIN 0.0 1.0 Gain
BMAJ Output beam width (asec fwhm)
NBOXES 0.0 50.0 Number Clean boxes
CLBOX Clean boxes
DOTV -1.0 10000. TV display control
HELP SECTION
BSCLN
Task: Performs a Hogbom-like Clean on an image made by differencing two
beam-switched images. At present, the beam is just two Gaussians
(plus and minus) but position, width, strength corrections are
made. The standard Hogbom algorithm searches for the maximum
pixel in an image and sets a component at that pixel. BSCLN
has a beam with a plus point one throw away from a component in
one direction and a minus point one throw away in the opposite
direction. So the peak of the difference of the residual image
one plus throw from a pixel and one minus throw from that pixel
is where BSCLN places a component. It helps convergence to
have the throw length about an integer number of pixels.
This is an experimental algorithm. Please inform Eric Greisen
(egreisen@nrao.edu) of any experience you have with it.
Adverbs:
INNAME.....Input plus image name (name). Standard defaults.
INCLASS....Input plus image name (class). Standard defaults.
INSEQ......Input plus image name (seq. #). 0 => highest.
INDISK.....Disk drive # of input plus image. 0 => any.
IN2NAME....Input minus image name (name). Standard defaults.
IN2CLASS...Input minus image name (class). Standard defaults.
IN2SEQ.....Input minus image name (seq. #). 0 => highest.
IN2DISK....Disk drive # of input minus image. 0 => any.
OUTNAME....Output image name (name). Standard defaults.
OUTCLASS...Output image name (class). Standard defaults.
OUTSEQ.....Output image name (seq. #). 0 => highest unique.
OUTDISK....Disk drive # of output image. 0 => highest disk
number with sufficient space.
BLC........Bottom right corner in input image of desired subimage.
Default is entire image.
TRC........Top right corner in input image of desired subimage.
Default is entire image.
DPARM......(1) Throw correction factor. The throw is read from the
input image header as BSTHROW. 0 -> 1.
(2) Throw angle in degrees
(3) Ratio of plus beam to minus beam peaks. 0 -> 1.
(4) Correction factor for plus beam width. 0 -> 1.
(5) Correction factor for minus beam width. 0 -> 1.
NITER......Number of Clean iterations.
GAIN.......Clean loop gain
BMAJ.......Output beam width (asec fwhm)
NBOXES.....Number of Clean search areas.
CLBOX......Clean boxes: rectangular xmin,ymin,xmax,ymax and circular
-1,radius,xcenter,ycenter are supported.
DOTV.......<= 0 => no TV display. > 0 => display residual image
every DOTV iterations. There is no interaction.
EXPLAIN SECTION