diff options
Diffstat (limited to 'astro')
| -rwxr-xr-x | astro/oskar/jybeam2k.py | 19 |
1 files changed, 13 insertions, 6 deletions
diff --git a/astro/oskar/jybeam2k.py b/astro/oskar/jybeam2k.py index 76072e3..0f774c1 100755 --- a/astro/oskar/jybeam2k.py +++ b/astro/oskar/jybeam2k.py @@ -48,9 +48,13 @@ def main(): parser.add_argument("-C", "--clobber", dest="clobber", action="store_true", help="overwrite existing output file") + parser.add_argument("-b", "--beam", dest="beam", type=float, + help="instrumental beam size [arcsec^2] " + + "(=pi*bmajor*bminor/4/ln(2)) (default: obtain " + + "from the header BMAJ and BMIN keywords)") parser.add_argument("-f", "--frequency", dest="frequency", help="frequency [MHz] of the input image (NOTE: " + - "required if cannot get frequency from file header)") + "required if failed to obtain from the header)") parser.add_argument("infile", help="input FITS image file (NOTE: only single " + "frequency supported)") @@ -81,11 +85,14 @@ def main(): print("Frequency: %.2f [MHz]" % freq) # Elliptical Gaussian beam (full width at half power; FWHP) - bmajor = header["BMAJ"] * 3600 # [arcsec] - bminor = header["BMIN"] * 3600 # [arcsec] - beam = np.pi * bmajor*bminor / (4*np.log(2)) # [arcsec^2] - print("Beam area: %.2f [arcsec^2] (major: %.2f, minor: %.2f)" % - (beam, bmajor, bminor)) + if args.beam: + beam = args.beam + else: + bmajor = header["BMAJ"] * 3600 # [arcsec] + bminor = header["BMIN"] * 3600 # [arcsec] + beam = np.pi * bmajor*bminor / (4*np.log(2)) # [arcsec^2] + print("Beam: (%.2f, %.2f) [arcsec]" % (bmajor, bminor)) + print("Beam size: %.2f [arcsec^2]" % beam) equiv = au.brightness_temperature(beam*au.arcsec**2, freq*au.MHz) jybeam2k = au.Unit(unit).to(au.K, equivalencies=equiv) |