[daip] whole message

[Leonia Kogan]

Dorogoy Andrey,

You probably use APARM(1)=1. ATMCA (at this case) estimates the phase of 
the source as interpolation of the calculated phase difference between 
the two calibrators using the distances the calibrator1 -source and
calibrator2-source. Such an interpolation requires the source to be 
located near the line calibrator1-calibrator2.

So the warning is not about the separation of the sources  but about
deviation of the target source off the line calibrator1-calibrator2.

Quite possible you are better off using APARM(1) =2,3 or even 4

You should look the AIPS memo # 111
at www.nrao.edu  to see more details about using ATMCA.

Vsech blag

Leonid Kogan




Eric Greisen wrote:

> From: Andrei Sokolov <asokolov at uclan.ac.uk>
> To: analysts at nrao.edu
> Subject: ATMCA
> Date: Thu, 23 Nov 2006 11:46:50 +0000
> 
> Hello,
> 
> I've tried to use the new procedure called ATMCA for our phase-reference experiment
> and it finished with the following message
> 
> gl1.st> ATMCA1: Task ATMCA  (release of 31DEC06) begins
> gl1.st> ATMCA1: Copied CL file from vol/cno/vers  3   75   3 to  3   75   4
> gl1.st> ATMCA1: Copied SN file from vol/cno/vers  3   75   2 to  3   75   4
> gl1.st> ATMCA1:
> gl1.st> ATMCA1: !! Intermediate SN table   4 created !!
> gl1.st> ATMCA1: Copied SN file from vol/cno/vers  3   75   4 to  3   75   3
> gl1.st> ATMCA1: ZTXOP2: using translated file name =
> gl1.st> ATMCA1: ZTXOP2: /gl1/work/as/ATMCA/atmca.slopes
> gl1.st> ATMCA1: -----------CL table outputs warnings:-----------
> gl1.st> ATMCA1:
> gl1.st> ATMCA1:
> gl1.st> ATMCA1: -----------SN table outputs warnings:-----------
> gl1.st> ATMCA1: | The angle Source 2207+374                                   |
> gl1.st> ATMCA1: | to Reference BLLAC            to Calibrator 2151+431        |
> gl1.st> ATMCA1: | is 40.3 degrees and exceeds the threshold 30 degrees        |
> gl1.st> ATMCA1: | So the CALIBRATOR is not used with the SOURCE               |
> gl1.st> ATMCA1:
> gl1.st> ATMCA1: | The angle Source 2151+431                                   |
> gl1.st> ATMCA1: | to Reference BLLAC            to Calibrator 2207+374        |
> gl1.st> ATMCA1: | is 40.3 degrees and exceeds the threshold 30 degrees        |
> gl1.st> ATMCA1: | So the CALIBRATOR is not used with the SOURCE               |
> gl1.st> ATMCA1:
> gl1.st> ATMCA1:    486 records of the CL table  4 modified
> gl1.st> ATMCA1:    390 records of the output SN table  3 modified
> gl1.st> ATMCA1: Appears to have ended successfully
> 
> How do I interprete the phase "is 40.3 degrees and exceeds the threshold 30 degrees. So the CALIBRATOR is not used with the SOURCE"?
> Our calibrators are quite close to BL Lac, about 1 and 5 degrees away.
> 
> thanks,
> Andrei
> 
> _______________________________________________
> Daip mailing list
> Daip at listmgr.cv.nrao.edu
> http://listmgr.cv.nrao.edu/mailman/listinfo/daip