[daip] frequencies from listr?
Mark Thompson
mat at star.ukc.ac.uk
Mon Jun 18 10:00:18 EDT 2001
I have a couple of questions about the frequencies that listr gives out when
you run it in optype='scan' mode to list each scan and the FreqID. Any
help you could give me would be very much appreciated.
When I run listr in this mode it gives me:
1) a list of all the scans taken with the source name, FreqID and visiblities
2) a source summary
3) a table of sources, velocity and rest frequency
4) a Frequency Table summary
The two questions I have are that the Source summary table (2) gives the
velocity type as topocentric. This is a little worrying as I was hoping
that the LSR velocity is taken into account somewhere, not the
topocentric velocity. Is this anything to worry about?
The main problem I am having is with the frequencies in the frequency
table (4). Are they given as sky frequencies? (the same as in imh)
I have a multi-frequency galactic dataset with many sources of different
LSR velocity. I am trying to read them in with FILLM and get everything
to line up properly in frequency. If the frequencies given are sky
frequencies then the LSR correction should be OK as it will come later.
If the frequencies aren't then something has gone very wrong with the
data and the lines probably aren't centred in the band.
Any help you can give would be very much appreciated.
Thanks
Mark
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