o-smirnov
commented
9 years ago Yeah OK I see what's going on. The *.pat files indeed contain the X and Y response to H polarization. Which one is extracted is determined by the -x (default) or -y option. Note that H=Y on the sky (confusing but true). The default therefore is to extract the X response to the H(Y) component, i.e. the XY pattern, as we suspected.
You do realize a beam consists of four complex patterns, i.e. the E-Jones matrix, ordered as [[XX,XY],[YX,YY]], right? So you need to generate all four, using the following combinations of options:
for XX: --rotate 90 -y
for XY: -x
for YX: --rotate 90
for YY: -y
I reserve the right to have something the wrong way 'round here, so do that and post the four amplitude beams here, we'll see if they make sense.
Ermiasabebe
The command to produce the primary beam model for the KAT7 from ASCII beam patterns to FITS files is:
for t in ampl real imag; do emss2fits.py --freqs=1440,1442,1445,1447,1450,1452,1455,1457,1460 --labels=a,b,c,d,e,f,g --$t -n 26 --scale=1.125 -d 0.78125 ../Patterns_origin/K7s_originh@freq_@label.pat KAT7_H-chan-21-default-scale-1.125-delfreq-0.78125-$t; done
The images produced are:
These images seem for the XY or YX polarization. The ASCII file for the KAT7 only contains for horizontal polarization (i.e /Patterns_origin/K7s_originh@freq_@label.pat; where h refers to horizontal). I assume that these files will produce the XX polarization, but it produces the above images.
In the "emss2fits.py -h", there is no option to produce XX or YY polarizations. It only gives ampl, real, and imag that can be produced based on the given ASCII file.
Any suggestion how XX and YY polarizations (i.e ampl, real, imag) based on the given "K7s_originh@freq_@label.pat"