Subject: Minutes of September 9 User's Committee Phonecon

From: strauss@astro.Princeton.EDU

Submitted: Mon, 9 Sep 1996 14:32:06 -0400 (EDT)

Message number: 79 (previous: 78, next: 80 up: Index)

   Minutes of APO 3.5m User's Committee Phone Conference
			September 9, 1996

   Attending: Alan Uomoto, Bruce Gillespie, Ed Turner (Chair), Lew
Hobbs, Jeff Brown, Michael Strauss (taking minutes), Rene Walterbos,
Chris Stubbs

July's meeting minutes are approved.

Baltimore meeting: New Instruments
extinction measurements at APO
plans for posting technical documentation at APO
policies for allocating daytime, twilight observing

**********Baltimore meeting: New Instruments************

   We did not have an August meeting. The Baltimore meeting (8/9),
where we discussed the status of observatory had many of us there.
Bruce Gillespie will distribute minutes from that meeting to
apo35-general.  Alan Uomoto is preparing a three-year plan for ARC
Board of Governors (meeting September 16), to be distributed
soon. Formal approval of it would be at Board meeting in November.
There is a fair amount of optimism that the Board will support us

   How will next generation of instruments be built?  Our current
model: if an institution builds an instrument, it gets "paid back" in
terms of increased observing fraction, meaning a readjustment of
institutional shares with each new instrument.  This made sense when
ARC got started, but it is not clear whether it continues to make
sense.  One idea, floated in Baltimore, is that in the long term
(i.e., after current immediate problems are fixed), there be some
funds, taken from the institutions at the level of a $1-few x
10^5/year (an instrumentation fund), which could be used as seed money for
building of instruments.  No permanent re-arrangement of observing
shares!  The director would have discretionary time (like engineering
time now) for new instruments, both for commissioning, but also
science time for the instrument builders (sort of like "guaranteed
time observers" with HST), which would give the instrument builders
some incentive.

  -- People agreed that the current model is unworkable. 

  -- We definitely need a *continuous* effort on new instrument

  How much do instruments cost?  Instruments are ~$10^6 each, they
last about 5 years, and you want three or four of them at any one
time.  Therefore, cost of instruments for the telescope would close to
our current operating budget ($500,000/year).  Kibblewhite says that a
"typical" operating budget for a 4-m telescope is $10^6/year. 
  Hobbs: Institutions very much want to keep operating costs very
low ($250K/year in 1985 dollars was the original plan). 

  Walterbos: Build instruments that can be improved after 5 years, not
thrown away at the end. 

***********extinction measurements at APO***********

  There will be soon a photometric archive coming out of the Sloan
Monitor Telescope, giving the photometric solutions (e.g., extinction)
on the SDSS system.  These can be used by everyone on the mountain,
although it remains to be demonstrated that extinction measured on the
3.5m in one filter system is equal to that interpolated from the SDSS
filter system extinction on the Monitor Telescope. 

***plans for posting technical documentation at APO******

   This is something we've already wanted to do, but has never been at
very high priority.  User's manuals should really be done by the users
themselves: Alan Watson and James Rhoads have volunteered to put
together such a manual for GRIM II.

   There is actually quite a bit of documentation on various things on
the web.  If we want to keep costs low, we can't put in a lot of
observatory resources.  So how are things working now? People have
built up a certain amount of expertise, but there are probably less
efficient than they would be with a good manual in hand.  There is
much expertise in the heads of the observing specialists.  Strauss
volunteers to put together a list of what documentation exists, and
what is needed.

*******policies for allocating daytime, twilight observing**********

  All telescope time is allocated and counted from twilight to
twilight.  So who gets the time immediately preceeding and following
the twilight?  Does the observer with the adjacent half-night have
rights to the twilight?  If we want to make this explicit, do we want
to charge institutions for this time? (right now, it is given out "for
free").  A suggestion: on proposal form, ask the question explicitly:
do you need the twilight time adjacent to your assigned time?  The
observer of the adjacent half-night would have "right of first
refusal" on this time.  People were happy with this.

Gillespie:  A lot of people are not specifying the instrument that
they want on the proposal.  Let the telescope people know which
instrument you want to start with as soon as possible (at least by

Next meeting, Monday, October 14, 12:30 PM. 
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