[daip] question about weights in FITS-IDI
Walter Brisken
wbrisken at nrao.edu
Fri Mar 21 14:38:31 EDT 2008
The weight vector that accompanies a visibility record stores weights on a
per IF / per polarization basis. The documentation I have suggests that
this weight must be between 0 and 1.
Because of some subtleties in the DiFX software correlator, it is possible
for the data weight to be slightly greater than 1 (with a hypothetical
maximum of about 2). This occurs when the integration time is not an
exact multiple of the subintegration time. In these cases, some records
may have slightly less than full weight and some may have a bit more than
full weight. The mean weight would be 1 in the case of perfect data
playback.
Will these weights that can exceed 1 cause any unexpected problems within
AIPS?
Thanks,
Walter
More information about the Daip
mailing list