[daip] AIPS HELP

[Eric Greisen]

aletdewitt at webmail.co.za wrote:
> Good Day
> 
> I have some EVLA spectral line data that I am trying to reduce. I am
> mainly following the steps in Annexure B of the cookbook for spectral line
> data.
> 
> I did all the editing steps and I am working on the calibration steps
> right now. I have more that one freqid per source and have 1 flux
> calibrator, 1 phase calibrator and one source. I created 1 FG table and 4
> additional CL tables (1 for each freqID and each source) for my CH0 data.
> I then copied the 1 FG table and the 4 additional CL tables that I created
> to the line data.
> 
> I now have to calibrate the bandpass for the LINE data, BPASS. I am not
> sure which of the parameters are necessary for this task. INNAME will be
> my Line data and IN3NAME my CH0 data. CALSOUR will be my flux calibrator
> and FLAGVER is set to 1. Do I use DOCALIB -1 or 1 and do I have to do this
> for both FREQID  1 and 2 seperately, and do I specify the GAINUSE, and if
> I do which CL table do I use - the CL table for the flux calibrator for
> FREQID 1 and 2 seperately or not ?

Normally we recommend splitting the FREQIDs into separate files with 
UVCOP.  Do not use the IN3NAME optioon - instead divide by a local 
computed channel 0 BPASSPRM(5)=0   You will have to do the operations 
for each FREQID separately.  This is why we separate them.

The DOCALIB setting in BPASS (when not using the IN3NAME option) does 
not matter since the data will be normalized by themselves either record 
by record or on a scan average or after solution basis (see HELP re 
BPAASSP(5) and (10)).

Eric Greisen