Subject: 3.5-m Users Committee minutes 5/05/08

From: Bruce Gillespie

Submitted: Tue, 6 May 2008 08:03:03 -0600

Message number: 1102 (previous: 1101, next: 1103 up: Index)

             APO 3.5-m Users Committee Phonecon, 5/05/08

Attending:  Suzanne Hawley, Bruce Gillespie, Scott Anderson, John  
Bally, Mark Klaene, Jon Holtzman, Michael Strauss, Russet McMillan,  
and Remy Indebetouw

Absent: Al Harper, Jon Fulbright

Minutes taken by Bruce Gillespie


User feedback, comments from institutional representatives:

Princeton (Strauss) - Michael said the PU users were happy.

UVa (Indebetouw) - Remy said that there was "no unhappiness" among UVa  

UW (Anderson) - Scott mentioned that two UW users have recently had  
trouble starting TUI on Red Hat (4) platforms. The apparent workaround  
is to log off and then log back on. Russell Owen is looking into the  

CU (Bally) - John said he had heard nothing back from the CU users.

JHU (Fulbright) - no report.

NMSU (Holtzman) - Jon had nothing new to report on user feedback or  

UChicago (Harper) - no report.


Discussion of telescope/instruments report - Klaene:

The report is given below.  Mark provided updates on the forest  
closure and other items. There have been two fires burning both east  
and north of APO, although they are not likely to threaten the  
observatory. Recent high winds continue to degrade utility electrical  
power, and the backup generator, although usable, needs servicing  
sometime in the next couple of months. The telescope has been  
generally well-behaved, with some minor problems addressed in the  
report. Although the autofocus script is being tested, other work  
priorities will delay its initial release to users for a few months.  
We have recently adopted a modified dust policy: the Observing  
Specialists will open the telescope under borderline high dust  
conditions, and then assess the dust levels inside the open enclosure  
(with the pressurization fans running to help keep the air clean near  
the telescope) and use the in-enclosure dust readings to determine  
whether to stay open or not. This has enabled us to recently keep the  
telescope open under conditions that we would have normally not opened  
the telescope in the past, based solely on outside dust levels.

The replacement of the fan-out board for NIC-FPS is nearly completed;  
all indications are positive so far. The final instrument cool-down  
was delayed because the ion pump appeared to be broken, and it was  
replaced with a spare. Once NIC-FPS is cooled down, tests of the noise  
performance of the detector will be made, possibly in the next day or  
two. The N-F Fabry-Perot etalon was removed, and will be returned to  
CU for cryo-testing. If the etalon is still inoperative in the lab, it  
will be returned to the vendor for repairs. Parts needed for moving  
Agile to a permanent port (with a rotator) were received and are being  
assembled. We should be ready to move Agile in a couple of months.

Related to the recent problem with dust, Bruce mentioned that Mike  
Skrutskie had asked if we have any data on the K-band emissivity of  
the telescope (we don't). Now that we have two low-noise NIR  
instruments, telescope emissivity related to temperature and  
cleanliness of the optics is especially worthy of our attention. Mike  
suggested that we might be able to baseline and monitor telescope  
emissivity using NIC-FPS and/or TripleSpec. Everyone agreed that this  
is a good idea that someone (who?) should pursue.


3.5-m Telescope, Instruments, and CIF Projects Highlights, 3/24/08  
through 4/29/08

                    Mark Klaene & Bruce Gillespie

0) Overview

Operations continued to be largely routine through the period. The  
spring weather (with its seasonal high winds and elevated dust levels)  
has affected observing--we lost approximately 4.5 nights due the high  
winds and dust levels during this period. The fire danger level in the  
surrounding forest is now extremely high, and although the forest is  
going to be "closed" effective May 1 by the USFS, no impact to normal  
operations is expected.

On site-related matters, recent water usage at the site has been  
unusually high, and two underground water leaks were subsequently  
located and repaired. However, there appears to be a third leak  
somewhere that requires further investigation. Site electric power has  
been relatively unstable, due in part to the high winds that have  
caused grid fluctuations and outages. Although operational, our  
emergency backup generator has a fuel leak for which we are trying to  
locate a part.

1) Telescope

Tertiary rotation has become problematic again. The engineering staff  
is working hard to diagnose the problem, but progress is slow because  
the symptoms do not appear during daytime testing. Slippage of the  
main azimuth drive system was noticed during tracking early last week,  
and the problem was fixed with a slight preload adjustment and the  
servicing of the lower azimuth bearing. We started telescope and  
enclosure preventive maintenance, those annual items that can be done  
without a shutdown. An autofocus script is now available for initial  
testing by the Observing Specialists. The script uses the NA2 guider  
focus to adjust the secondary, and has had some limited testing to date.

2) Instruments

DIS, SPIcam, and the Echelle operated smoothly throughout the period.  
Echelle experienced a minor warm-up that was traced to a loose power  
connection. Shortly afterwards, the Echelle ion pump controller  
failed. We believe this was the source of the burnt odor noticed two  
months ago. A new ion pump controller was installed, and no further  
warm-up problems have been seen. The new fan-out board replacement for  
NIC-FPS and the etalon removal work has started.

With the arrival of TripleSpec, CorMASS has been decommissioned and  
crated for shipment back to UVa in the upcoming weeks. The visiting  
instruments (GFP and APOLLO) were both operational. TripleSpec  
commissioning began and the new instrument is well on the way to being  
available for scheduled science. Some TripleSpec first-light  
information is available--contact John Wilson at UVa if you are  
interested. We are also planning to place preliminary TripleSpec user  
documentation on the web soon.

3) CIF projects

We are making good progress on the implementation of Agile field  
rotation and its migration to the TR2 mirror cell port. Most of the  
new parts have been received and initial assembly is underway, to be  
followed by bench testing. The tertiary support/actuator upgrade is  
progressing; long-lead items have been purchased, and machining has  
started. Design is slightly behind schedule but still on track for an  
August installation. The rotator drive upgrade has been in routine  
operational use for some time now, and indications are that its  
performance requirements appear to have been met. Ongoing cleanup of  
rotator controller software will continue over the coming months,  
which will enable the migration of the new axis controller system to  
the telescope altitude drive.

4) Summer Shutdowns

There will be three shutdown periods this summer. Two 3-day shutdowns,  
one in June and one in July, will be for secondary and axis drive  
work. In August, we are planning a 17-day shutdown for the tertiary  
support upgrade, as well as for M1 washing and several additional  
maintenance tasks (e.g., annual instrument servicing).


Q3 Summer shutown dates - Hawley:

Suzanne said that that the major summer shutdown will occur 6 - 22  
August (inclusive), and a mini-shutdown will be scheduled for 14 - 16  


TripleSpec update - Indebetouw, Hawley:

Remy said that UVa is pleased with the progress in commissioning  
TripleSpec. The online user documentation should be posted this week,  
and the data reduction software is very near completed and ready for  
users. Suzanne added that TripleSpec had two engineering runs during  
March and April, and that the TUI control functions appear to be in  
place. The instrument will be offered to the general user community  
this summer in a shared-risk, block-scheduled manner. The blocks will  
be scheduled in 4 or 5 contiguous nights, so that UVa staff can be on  
call to field questions. Data taken during the coming quarter will be  
user-proprietary. Russet added that since we are block-scheduling  
TripleSpec to enable UVa support, it will not be available as a fill- 
in or back-up instrument outside of the scheduled blocks. If users  
wish to write a TripleSpec proposal for the coming quarter, Suzanne  
said that there is a link on the APO instrument information webpage to  
the UVa documentation, and people should contact John Wilson (jcw6z at if there are questions not covered in the documentation.  
In addition, TripleSpec data already taken during the engineering runs  
will continue to be available for prospective users to look at;  
contact Suzanne or Bruce for the URL. Suzanne asked that the User  
Committee members should make sure that their users are aware that  
TripleSpec is being made available in the coming quarter.


NIC-FPS update - Bally:

In addition to news about NIC-FPS that is covered in the reports  
above, Stephane Beland and Mike Kaiser (from CU, CASA) have been at  
APO installing the new fan-out board and removing the F-P etalon. In  
the next day or two, full-up tests of the detector will be possible to  
see if the new wiring improves the detector noise characteristics.



[open from previous months]:

ACTION:  John Bally will write a section with figures on Fowler  
sampling for inclusion in the NIC-FPS user documentation.

STATUS:  Closed. John recently reviewed the section and made editorial  
comments, which were implemented by Gabrelle Saurage. In general,  
Suzanne asked that we remind all users that we depend on their  
feedback for improving the 3.5-m telescope, instrumentation, and  
software user documentation on an ongoing basis.

[new actions from this month]:



Future of the Photometric Telescope - Hawley, Gillespie:

Although not on the agenda, Suzanne and Bruce reported on an item  
discussed at the recent ARC Board of Governors telecon. The Board  
agreed with the plan to assume operational responsibility of the PT  
after SDSS-II ends on 14 July. Proposals for post-SDSS programs for  
the PT have been received and are being evaluated. At the November  
annual Board meeting, we will make a recommendation on which future  
program(s) to conduct on the PT, with a plan for managing and funding  
said program(s).


Next meeting:

The next Users Committee phonecon will be on Monday, 9 Jun, at 8:30 AM  
Pacific Time.  The agenda and other materials will be sent to the  
committee members during the preceding week.

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