Subject: Arranging trades/switches in the observing schedule

From: Ed Turner

Submitted: Mon, 22 Sep 2003 10:26:08 -0400 (EDT)

Message number: 706 (previous: 705, next: 707 up: Index)

Subsequent to the distribution of the preliminary 4Q observing schedule on 
Saturday, I received several requests from various PIs on scheduled 4Q 
programs to try to find trades or switches with other scheduled programs 
for them that would make their time allotments more effective.

First, I should note that is quite possible, likely even, that such trades 
are possible and desirable (in that they would help both programs).  I 
cannot pretend that the schedule I devise is even approximately optimal 
given all the many constraints and preferences.

Second however, I have to remind everyone that it is the PI's 
responsibility to find and arrange any such trades by contacting other PIs 
and the institutional scheduler(s) concerned.  After a bit of early 
experimentation years ago, I found that it simply takes way too much of my 
time to do this job for the PIs and is quite inefficient too, in that I 
typically ended up simply being a middle-man in some correspondence 
between the PIs and scheduler(s) concerned.  Waiting for me to pass the 
requests and responses back and forths only slows the process down.

So, if you would like to make a time trade to improve the value of your 
scheduled 3.5m time, please do try to arrange it one by contacting other 
PIs who have suitable time slots.  This can only serve to improve the 
effectiveness with which we employ the telescope as is thus a "good 
thing".  All of the information that you might need to select good 
prospects for such trades, including contact info and the scheduling 
constraints of other programs, is available in the online version of the 

Two additional points:

1) If possible, please arrange any such switches and send the request for 
approval to me and the relevant APO staff at least a week in advance of 
the first affected observing time.  However, if some circumstance requires 
you to make a last minute trade, this one week advanced notice should 
not be regarded as a hard limit.  We can and often have changed the 
schedule with very much less notice.  It is simply a courtesy and 
decreases the liklihood of glitches (like having the wrong instrument 
mounted at the beginning of the night).

2) Please use the ascii template available in message #200 of 
apo35-general to formally request approval of the trade (it is rare that 
one would not be approved if all concerned PIs and schedulers agree to it) 
and to inform all concerned.

Ed Turner

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