Data Weights Discussion
(1) Ability to properly calibrate data weights based on Tsys. Central to=20
this feature is elevation dependent opacity correction. To get a wide=20
range of users involved, CASA must recognize Tsys information from:=20
VLA/eVLA, SMA, CARMA, ALMA, Plateau de Bure, Nobeyama, ATCA.
Currently for the VLA the Tsys is used to scale both the data and the weights (this
is done online, I believe. For other telescopes, I'm not sure how this is handled but
the key issue seems to be that you always do the same thing to the data as the weights
(i.e., scale by Tsys or not to both). We have one target currently to calibrate the weights as
part of the calibration process. As for the opacity correction, this is done as a
function of elevation; we'll need confirmation that the interface is adequate for
this solving/application. I'm hoping that the calibration of weights target will close
out this issue.
- 25 Oct 2006