[daip] Coordinate Systems question

[Shami Chatterjee]

Hi Pat,
I had an aips coordinate system question for which you might have a
simple answer:

I'm working on an archival VLA data set (A array, C band, 0.3 asec
resolution) which was taken in B1950 coordinates. And the aips eposwtch
verb warns that it is "of adequate accuracy for normal imaging but should
not be used in astrometric circumstances."

In order to convert coordinates of detected point sources back to J2000, I
need to know: is the implied reference frame FK4 for B1950, FK5 for J2000?

And what do you recommend for the conversion?
Thanks,
Shami
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 Shami Chatterjee     http://www.astro.cornell.edu/~shami/

 Oppenheimer's Observation: The optimist thinks this is the
 best of all possible worlds, and the pessimist knows it.
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