[daip] VTESS

[rlaing at eso.org]

Dear Eric et al.

We are comparing some new results with previously published images, and this
raised a question about VTESS, specifically the change which was reported in
AIPSletter XXIII no 2 (the 2003 Dec 31 release). There, it is reported:

VTESS and the other tessellation tasks were changed to use the standard primary
beam routines. The default is now to apply a primary beam correction.

This implies that the previous default was NOT to apply a correction even for
VLA data. Looking back at the history files for some of our published images
suggests that this was indeed the case, e.g.:

  8510  VTESS  PBCENX( 1), PBCENY( 1) = 1024.41,2049.21 /Pixels
  8511  VTESS  NOISE( 1) =   6.300E-06/ Jy/beam
  8512  VTESS  /Field  1 : Interferometer  data
  8513  VTESS  /Field  1 : No primary beam correction

My questions are:

(1) Is this correct and

(2) Does FLUX apply after application of the primary beam correction? The HELP
    calls it the zero-spacing flux density, which is ambiguous in this contect,
    I think. 

Regards

Robert

-- 
Robert Laing
European ALMA Instrument Scientist

European Southern Observatory
Karl-Schwarzschild-Strasse 2
D-85748 Garching-bei-Muenchen
Germany

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rlaing at eso.org