[daip] SETJY

[Andreas Brunthaler]

Dear Eric,

I hope you are all back at work now in Socorro. I'm having some problems 
with the velocity calculation in SETJY. I compared the results I get 
when using the 31DEC2011 and the 31DEC2013 versions and get different 
results for the same input parameters.

I'm using OPTYPE '' and the following information:

SYSVEL       18
RESTFREQ   6.668E+09   519200
VELTYP     'LSR'
VELDEF     'RADIO'
APARM       501,0

Now, If I use the 31DEC2011 version, I get in the SU table:


COL. NO.            2                18                19
      ROW      SOURCE            LSRVEL            RESTFREQ
   NUMBER                        M/SEC             HZ
        2      G000.31-0.20      1.978371D+05      6.668519D+09


In the 31DEC2013 version, I get:


COL. NO.            2                18                19
      ROW      SOURCE            LSRVEL            RESTFREQ
   NUMBER                        M/SEC             HZ
        2      G000.31-0.20      179825.49691      6668519456.0


If I use OPTYPE = 'VCAL' in the 31DEC2013 version, I get yet another value:


COL. NO.            2                18                19
      ROW      SOURCE            LSRVEL            RESTFREQ
   NUMBER                        M/SEC             HZ
        2      G000.31-0.20      233796.30089      6668519456.0

Apart from the different values I also get a different format. Now, if I 
run CVEL on this, I get shifts of < 1 channel for the 31DEC2011 version 
(as expected). However, for the 31DEC2013 version, I get shifts of 50 
channels (using OPTYPE='') and 100 channels (using OPTYPE='VCAL'), which 
corresponds to the velocity offsets above.

Any idea where this difference comes from?

Andreas

-- 
   \_________________________________________________________________

  Andreas Brunthaler
  Max-Planck-Institut fuer Radioastronomie

  Auf dem Huegel 69            Tel.   :  +49 228 525 377
  53121 Bonn                   Fax    :  +49 228 525 229
  Germany                      e-mail :  brunthal at mpifr-bonn.mpg.de
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