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Best way to get specturm of point source

Posted: Tue Dec 01, 2015 3:18 am
by Kingsley
Hello
I have a field with several point sources in it and wish to find the spectrum of each.
I've imaged up with the desired frequency resolution and done a continuum subtraction.
At the moment I've loaded the cube up in CASA viewer and used the ellipse tool for each object to produce a spectrum.
Is there a more direct method in MIRIAD? I would suspect that imspec would do it (by specifying the pointing offset and the size of the source?) Does imspec deal with primary beam weighting? would there be any benefits from either approach or is there a better way to do it?

Thanks
k

Re: Best way to get specturm of point source

Posted: Tue Dec 01, 2015 10:08 am
by Mark.Wieringa
Hi Kingsley,

I don't think there is a more direct method. In Miriad you can do a similar thing, specify a region for each source, and a cutoff level, and use imspec to produce a spectrum, but it is not better in any way other than that you can put the commands in a script and rerun it easily.
Imspec doesn't do primary beam weighting (even though it mentions it, it was never implemented), but you can run your cube through linmos first to do primary beam correction.

Cheers,

Mark