[mmaimcal] Re: [alma-sw-ssr] mosaicing

[Bryan Butler]

some of you may be interested in this...

	-bryan


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>From owner-alma-sw-ssr at kochab.cv.nrao.edu Thu Jun 29 12:06 MDT 2000
Date: Thu, 29 Jun 2000 11:01:54 -0700 (PDT)
From: mel wright 456 <wright at creek2.berkeley.edu>
To: alma-sw-ssr at cv3.cv.nrao.edu
Subject: Re: [alma-sw-ssr] mosaicing
Cc: mholdawa at cv3.cv.nrao.edu
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Here's another detail which is bothering me. Perhaps someone can
resolve for me.

For Nyquist sampling of pointing and uv-data, the phase varies by
pi for a source at the edge of the field of view; the amplitude
of that source is attenuated by 2/pi on the Nyquist sampled long
baseline, by less on the short baselines. In the mosaicing
algorithms, shouldn't the 'primary' beam correction also include
a correction for this attenuation ?  Is this one reason why I see
an increase in image fidelity when I oversample the data ?

Melvyn.


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