[daip] subtle differences in images

[Min S. Yun]

I am trying to combine the VLA mosaic observation data with the 
GBT data using UTESS.  UTESS runs fine if I use just the VLA data,
but it behaves strangely as soon as I offer the GBT data, either
as one of the inputs or to be used as the default image.  My
suspicion is that the beam information is not fully specified
for the GBT data, and AIPS does not know exactly how to interpret
"Jy/beam" and the beam information given in the header -- the
header for the GBT data says BUNIT is JY/BEAM and apparently
has the correct BMAJ, BMIN, and BPA info.  Why do I suspect this
is where the problem lies?  When I do a TVSTAT on a VLA image,
I get the ususal stats and the total flux information.  If I
do the same on the GBT image, I do not get the total flux
information nor the "number of pixels per beam" report.  Is
there another header information AIPS requires besides 
BMAJ, BMIN, BPA, and CELLSIZE to calculate the number of cells
per beam?  Thanks in advance for any insight you could offer.


					-- Min


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Min S. Yun				e-mail: myun at astro.umass.edu
Associate Professor			phone:  (413) 545-2215
Astronomy Department			FAX:    (413) 545-4223
University of Massachusetts             http://www.astro.umass.edu/~myun
Amherst, MA 01003