[daip] Probleme reducing data

Eric Greisen egreisen at nrao.edu
Fri Nov 9 11:54:36 EST 2007


I have taken a look at your data and there really is a problem - not
with CALIB but with your data.  Plotting the flux cals 3C147 and 3C286
reveals low fluxes with enormous scatter and many missing baselines.
No solutions were found since there are not solutions to be found on
those sources.

Looking at the run as a whole - there are an enormous number of 'C'
calibrators and there is no way that two very short scans on the basic
cals will allow you to calibrate all of those fluxes.  I do not see
how you can calibrate these data.  If you enter by hand the "known"
fluxes (not accurate vs time) for each cal source, then perhaps you
can make some progress.

The problem seems to be at both X and U bands in the earlier A-array
portion of your data.  Plotting the cals from the B array portion
shows very stable amplitudes and things should go better with those
data - although calibrating all of the calibrators is still a problem.
Note too - check the SCAN output of LISTR.  There is at least one
source observed under the same name with different positions.  FILLM
has added characters to the end of the source name to differentiate.

Eric Greisen




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