From marscher@buast0.bu.eduWed May 15 08:32:13 2002
Date: Tue, 14 May 2002 16:29:14 -0400 (EDT)
From: Alan Marscher <marscher@buast0.bu.edu>
To: schedsoc@cv3.cv.nrao.edu
Cc: bclark@cv3.cv.nrao.edu, cwalker@cv3.cv.nrao.edu, vlbiobs@cv3.cv.nrao.edu,
    julvesta@cv3.cv.nrao.edu
Subject: Observing requirements for BM171 (dynamically scheduled)

Dear Barry et al.,

Here are the observing requirements for BM171 (dynamically scheduled
for 12 ~ monthly observations). I worry that they may be too complex
to incorporate into an automatic routine. The truth is that we
can compromise on some of the observations but do need some
epochs with near-optimal data quality to anchor the lower quality
images. This is especially true for the phase referencing where
having a set of at least 4 good epochs over a year is very important,
but having 4 good epochs in a row is helpful but not so crucial.

Here are the criteria:

Observations need to be carried out monthly but do not need to be on
   the same day every month. Please try to avoid skipping a month
   altogether: Even a spacing of 50 days and then 10 days would be
   useful, since the time scale for variations can be very short.
At least one epoch every 3 months needs to be with all antennas.
   No epoch should have fewer than 8 antennas.
   We always need MK; without it the data are nearly useless.
At least one epoch every 3 months needs to have excellent weather
   across some of the baselines to MK for accurate phase referencing.

Thanks very much,
Al Marscher