Image Analysis with CASA - ESO

If only 1 Gaussian component (default), the fit will do without prior guess.
If more, estimates have to be input from a file containing (for each component):
peak intensity, peak xpix value, peak ypix value, major axis, minor axis, position angle, fixed
fixed = combination of: f x y a b p, for the parameters to be kept constant
Example: Simultaneous fit of 2 Gaussian components, the first one fixed in xy position
prior_guess=open(’input­parameter.estimate’,’w’)
print >> prior_guess,’# peak, x, y, bmaj, bmin, pa’
print >> prior_guess,’0.02, 128, 128, 0.4arcsec, 0.2arcsec, 120deg, xy'
print >> prior_guess,’0.01, 113, 120, 0.4arcsec, 0.2arcsec, 120deg'
prior_guess.close()
xfit = imfit( imagename=’my.image’,
estimates=’input­parameter.estimate’,
logfile='fit­results.log’,
box=’118,118,138,138,103,110,110,130')
Results are returned as a Python dictionary (xfit) + can be written in a logfile
or a component list table
If the image has a clean beam, the report will contain both the convolved and the deconvolved fit results.
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