Subject: APO 3.5-m Users Committee minutes 4/19/04

From: Bruce Gillespie

Submitted: Fri, 23 Apr 2004 10:14:36 -0600

Message number: 774 (previous: 773, next: 775 up: Index)

					APO 3.5-m Users Committee Phonecon, 4/19/04

Attending:  Ed Turner, Michael Strauss, Bruce Gillespie, John Bally, 
Fred Hearty, Cynthia Froning, Russet McMillan, Rene Walterbos, Jon 

Absent:  Don York, Bruce Balick, Karl Glazebrook, Al Harper

Minutes taken by Bruce Gillespie


Summer shutdown plans:

Bruce Gillespie reported the planned dates and work list for the '04 
summer shutdown.  The planned start/finish dates are 28 June through 13 
August.  Work is planned for DIS and its slit viewer, realuminization 
of the 2ndary, tertiary mirror wiring improvements, primary mirror 
washing, and vacuum pumping of DIS and SPIcam.  Also planned for late 
in the shutdown is the delivery of NIC-FPS to APO--Fred Hearty needs to 
contact Mark Klaene to coordinate the delivery and integration.  The 
length of the shutdown is about what we usually take, but the work 
scope is a little lighter than in past years, in part because we have 
uncertain levels of manpower for the shutdown and that we want to avoid 
"hero mode" for the work.  There is a possibility that the shutdown 
could end early, and what to do with the leftover time was discussed.  
The most popular options seemed to be to schedule low-priority 
provisional programs in the last week or so of the shutdown that could 
be cancelled if needed, or to give any contingency time to NIC-FPS for 
commissioning tests, if it were ready for on-sky use.  Ed will decide 
how to allocate this provisional time when he makes the call for the 
next quarter proposals in early May.


NIC-FPS report:

Fred Hearty and Cynthia Froning (NIC-FPS Program Manager) reported that 
the NIC-FPS mechanical systems are undergoing integration and testing, 
which is going well.  The filter wheel assemblies and etalon mover are 
the main focus at the moment, and the cables (and spare cables) are 
being assembled.  It is expected that the "bench" will be fully 
integrated in about a month, and that the detector will be joined to it 
shortly thereafter.  Detector testing has been plagued by configuration 
problems, but they have recently taken an image with it in the lab.  
Delivery of NIC-FPS to APO is planned for 1 August.


DIS Blue noise gone?:

Jon Holtzman said that through some recommendations and tests by 
various people, it appears that the low-level pattern noise in DIS Blue 
has been reduced about a factor of 10, making it virtually nonexistent. 
  The key fix was in replacing the clock cable to the blue dewar.  Jon 
said that this episode shows we have at least two bigger problems:  Why 
did it take so long for us to discover that the blue camera had this 
noise--users of DIS should have noticed this months ago and alerted the 
observatory staff.  Users need to be reminded that they have an 
obligation and duty to report anomalies they detect with the 
observatory systems.  Also, Jon suggests that some kind of monitoring 
and trending program needs to be instituted to watch for these kinds of 
telescope and instrument performance degradations.  The second problem 
is that the 3.5-m telescope is seriously shorthanded in expertise on 
instrumentation and electronics, owing to the recent departures of 
several key people at various 3.5-m consortium institutions.  Bruce 
Gillespie made the point that the 3.5-m consortium institutions should 
consider this to be an "opportunity" for an in-house person (or 
persons) to get involved with electronics and instrumentation projects 
at APO.


Integral Field Spectrograph report:

John Bally reported that he is revising the instrument concept to 
accommodate a larger lenslet scale, and that this requirement is 
driving some interesting, albeit challenging, design changes.  He plans 
to update the white paper that describes the instrument in the next few 
weeks.  No feedback has been received from the CFHT on their potential 
interest in such an instrument.


New Instrument Call for Proposals:

Ed is preparing a CP for a new ARC instrument for the 3.5-m, which will 
have provisions for significant CIF funding support, plus an allowance 
of Director's Discretionary time for commissioning and science 
programs.  The proposals would be due this summer, with a late summer 
decision likely.  The issuance of the CP has been delayed, but will 
probably be launched within the next few weeks.


CorMASS is coming, last call:

Bruce Gillespie again reminded the user community that the low-res NIR 
spectrograph CorMASS has arrived at APO, with commissioning runs 
scheduled for 3 - 7 May.  If users are interested in any tests or 
science commissioning experiments during this run, they should contact 
Bruce Gillespie (  More information on the 
capabilities of CorMass will be posted shortly to apo35general.


CIF projects:

Bruce Gillespie reported that the design of the NA2 light baffle is 
done, and that fabrication is beginning at the Sunspot shop.  
Completion of the baffle is likely to take several months, and probably 
won't be installed in the telescope until after the summer shutdown.  
Design work for the new "top-end" continues, with a set of M2 
requirements being posted by Jon Davis for review.


Split-nights discussion:

The group discussed ways of mitigating the problem caused by having a 
short program scheduled at the beginning of a half-night, thus taking 
away the twilight calibration time, and in summer, leaving the residual 
half night program without much time to do useful observing.  Various 
policies were discussed which had a variety of pros and cons, and no 
real consensus was reached.  One idea offered was to limit each night, 
maybe only in the summer months, to a maximum of two programs per 
night, however long the programs are.  If there were a short program at 
the beginning or end of the night, the other program gets the entire 
remainder of the night.  This ensures that every program gets twilight 
for calibrations, but adds yet another scheduling constraint that will 
complicate scheduling.  Ed will ponder the problem some more, and 
invites others to send him opinions and ideas.


10Mb/sec Internet coming to APO?:

Bruce Gillespie reported that we have been given US Forest Service 
permission to have a high-speed microwave internet system installed at 
APO, which if it works, would give us a tenfold increase in bandwidth 
at the site.  It may take a few months to get the contract and hardware 
in place, and then there will be an evaluation period before we cut the 
cord to our current T1 service.


10th anniversary celebration:

There was a brief discussion of the 10th anniversary celebration, and 
the turnout and contributed science talks are looking to be fairly 
substantial.  The deadline for making reservations is this week, but if 
people discover later that they can come, we will find a way to fit you 
in and get you accommodations.


Last month's minutes were approved without comment.

Next phonecon will be on Monday, May 10, 2004, at 11:30 AM Eastern Time


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