AIPS HELP file for CXPOLN in 31DEC22
As of Fri Dec 1 13:12:03 2023
CXPOLN: Procedure to make complex polarization images and beam
Use RUN CXPOLN first
INNAME UV file name (name)
INCLASS UV file name (class)
INSEQ 0.0 9999.0 UV file name (seq. #)
INDISK 0.0 9.0 UV file disk drive #
OUTNAME Output Image name
OUTSEQ 1.0 9999.0 Output sequence number
OUTDISK 1.0 9.0 Output disk
BIF 0.0 100.0 Lowest IF number 0=>all
EIF 0.0 100.0 Highest IF number 0=>all
BCHAN 0.0 2048.0 Lowest channel number 0=>all
ECHAN 0.0 2048.0 Highest channel number
IMSIZE 32. 4096. Image size (X,Y) in pixels
CELLSIZE 1.E-12 (X,Y) size of grid in asec
RASHIFT RA shift (asec)
DECSHIFT DEC shift (asec)
UVTAPER 0. (U,V) gaussian taper
units are kilolambda
UVRANGE 0. Min & max baseline (klambda)
UVWTFN UV dist. weight function
blank => uniform
UVBOX 0. 128. Additional rows and columns
used in weighting. Use 0.
XTYPE 0. 10. Conv. function type in x
YTYPE 0. 10. Conv. function type in y
XPARM Conv. function parms for x
YPARM Conv. function parms for y
BADDISK Disk drive #'s to avoid
Procedure: This procedure will produce complex polarization images
using a combination of tasks UVPOL and IMAGR. The images are
then normalized such that the amplitude of the reference pixel
of the complex beam is 1.0. These images are suitable for
deconvolution using CXCLN.
Before attempting to use CXPOLN the RUN file CXPOLN must be
run to define the procedure. This is done by:
and only needs be done once.
CXPOLN creates several temporary files which it will destroy
if able. The names of these files are fixed and must be
destroyed if a previous attempt at CXPOLN failed. Also the
output files must not exist before running CXPOLN.
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.
OUTNAME....Output image name (name). Specify please.
Default is 'CXPOL output
This procedure will produce 4 images with classes
'QIM001', 'UIM001', 'QBM001', and 'UBM001'
OUTDISK....The disk drive # of output images. Default 1.
OUTSEQ.....Output sequence number. Default 99. It is best to
specify these things.
BIF........First IF to image. 0=>all.
EIF........Highest IF to image. 0=>all higher than BIF
BCHAN......First channel to image. 0=>all.
ECHAN......Highest channel to image. 0=>all higher than BIF
IMSIZE.....(X,Y) image size in pixels.
Must be a power of 2 on each side from 32X32
CELLSIZE...(X,Y) pixel separation in asec.
RASHIFT....RA shift of the phase center of field from the tangent
point of the uv data in asec. Map center = tangent point
+ shift. If X>0 shifts map center to east. NOTE:
RASHIFT and DECSHIFT are not strictly a shift in RA and
dec. The effect of RASHIFT on the RA of the map center is
roughtly RASHIFT/COS(dec). If the uv data has been
rotated then RASHIFT and DECSHIFT refer to X and Y in the
new coordinate system. NOTE: only does 1 field.
DECSHIFT...Declination shift of map center from tangent point of
field in asec. Map center = tangent point + shift. If
Y>0 shifts map center to north.
UVTAPER....(U,V) gaussian taper (kilolambda) at 30 percent level
UVRANGE....(Minimum,Maximum) baseline (kilolambda) in map.
UVWTFN.....Weighting function of (u-v) place.
UVBOX......(U,V) box size for smoothing. See HELP UVBOX
XTYPE......Convolution function type in X-direction
1=Pillbox, 2=exponential, 3=Sinc, 4=Exp*Sinc,
<= 0 or > 5 -> 5.
YTYPE.....Convolution function type in Y-direction
XPARM.....Array containing parameters for XTYPE.
See HELP UVnTYPE when n=convolution type.
YPARM.....Array containing parameters for YTYPE.
BADDISK...Disk drive #'s to avoid for scratch files