[daip] AIPS and BPASS

[Leonid Petrov]

Dear Eric,

  Thank you for your detailed answer.

> bpassp(5) = -1.  With 0, the data of each record are normalized in amp 
> and phase which can introduce a Ricean bias since the expeted amplitude 
> in the case of no signal is not zero.  VLBI often uses all channels so 
> bpassp(10) = 1 or 4 rather than 2.

  May I ask you a favor to shed a light how AIPS normalizes bandpass?
We found that applying bandpass increased the fringe amplitude by 5.8%
in our case of VLBA observations of strong sources. The phase of the bandpass
did not exceed 0.08 rad, so it is bandpass amplitude that caused the change
in the fringe amplitude. The average value of the bandpass that Yuri
generated with AIPS was not 1.

Sincerely,
Leonid
15-AUG-2013 17:40:33