Subject: 3.5-m Users Committee minutes 10/06/08

From: Bruce Gillespie

Submitted: Wed, 8 Oct 2008 13:49:11 -0600

Message number: 1115 (previous: 1114, next: 1116 up: Index)

       APO 3.5-m Users Committee Phonecon, 10/06/08

Attending:  Suzanne Hawley, Bruce Gillespie, Scott Anderson, Al  
Harper, Meredith Drosback (for Remy Indebetouw), Mark Klaene, Russet  
McMillan, Guy Stringfellow (for John Bally), Michael Strauss

Absent: Jon Holtzman, Jon Fulbright

Minutes taken by Bruce Gillespie


User feedback, comments from institutional representatives:

The only substantive comment on user feedback came from Suzanne  
Hawley.  She and her students have noticed that in TUI, the windowing  
function for DIS applies the same way for both the blue and red  
images--they can't be set separately, and the spectra appear at  
different places on the blue and red chips.  At a minimum, this  
"feature" should be highlighted in the users documentation, and  
possibly we should consider revising the software so that the DIS blue  
and red images can be windowed separately.


Discussion of telescope/instruments report - Klaene:

The report is given below.  Mark pointed to the recent spate of good  
weather and a well-behaved telescope.  Now that the future of SDSS-III  
is secured, we are beginning to spend funds that had been held back on  
needed site improvements.  We have continued diagnostic and repair  
work on the tertiary rotation system, and its geared encoder is now  
working better.  The tertiary homing problem is on the schedule for  
repair during October.  Current performance anomalies with DIS cryo  
and vacuum systems are being watched, and are hinting at future  
maintenance.  TripleSpec experienced a vacuum gauge failure, which is  
being replaced and an ion pump is being added to the instrument;  
TripleSpec should be ready for scheduled observations next week.  For  
CIF projects, we are close to permanently moving Agile to the TR2  
port, with its new rotator.  The new axes controllers are getting  
close to being put on the telescope, and planning for next year's  
direct-drive motor replacements in alt and az is underway.

Guy asked about the status of the loose wire recently found hanging  
into SPIcam's field of view.  Mark said that the loose wire was being  
re-secured.  Suzanne added a comment that as a part of the move of  
Agile to a new mirror-cell port, Agile instrument control will be  
implemented in TUI, probably by the end of the year.


3.5-m Telescope, Instruments, and CIF Projects Highlights, 9/6/08  
through 10/1/08

                               Mark Klaene

0) Overview

We have finally seen the end to the summer monsoons--the humidity has  
dropped and clearer skies are now the norm, and fall is definitely in  
the air.  The telescope has been working quite well, taking good  
advantage of the clear nights.  On site-related matters, we are  
nearing the completion of the installation of a new boiler for Dorm B  
and repair of the fire alarm system replacement will begin this week.

1) Telescope

Most of the problems with tertiary rotation have been fixed with the  
differential wiring modification done during the September engineering  
time.  New power supplies are on order to address the axial stepper  
motor noise, and these will be installed during the October  
engineering time.

2) Instruments

The DIS blue ion pump continues to run at high current, and we may  
need to open the dewar in the near future for servicing.  DIS red and  
SPIcam are fully operational with no problems.  Service was required  
on the DIS red cryotiger, which was accomplished during a recent  
period of poor weather.

Echelle and NIC-FPS remained cold and powered on during the shutdown.   
We are waiting for UVa to design and build a new NIC-FPS fan-out board  
that will hopefully reduce readout noise.

TripleSpec had to be warmed up due to a vacuum gauge failure, with the  
repair still in progress.  Most of the TripleSpec spare parts are now  
at the site, and final instrument acceptance is pending the delivery  
of documentation.

Agile has a new mask to reduce the light scattered around the CCD.   
The instrument rotator for the TR2 port is now in testing in the lab.

GFP is currently warm since it is not on the schedule until late  
November.  APOLLO remains operational, and has had a recent record- 
breaking run of of lunar-return photons.

3) CIF projects

New software was created for the altitude and az axis controllers, and  
is being tested on the rotation axis. Planning for next years CIF  
projects is in work. The major CIF project for next year is direct  
drives for azimuth and altitude axes.


Calibration (Flat, Arc lamps) upgrades - Klaene:

Mark mentioned that we have been looking at the suite of flat-field  
and emission-line calibration lamps on the telescope in the context of  
meeting users requirements for our new and upgraded instrumentation.   
Bill Ketzeback has been researching this topic, and we have identified  
possible improvements aimed at increasing the flux in the far blue/ 
near UV for DIS flat fields, and in providing additional lines for  
wavelength calibration in this part of the spectrum.  We are  
interested to hear if the other optical instruments, and especially  
the IR instruments, have adequate flat field and wavelength  
calibration capability from our present lamps or if improvements are  
desired.  Other improvements are possible and may be worth  
considering, such as more lamps, projector systems, fiber-fed cal  
sources, internal cal sources, etc.  Please contact us if you would  
like more information on the current system and possible upgrades.   
But in order to proceed, we need user feedback; Suzanne asked for an  
action item.

ACTION: The Users Committee representatives are to ask their  
respective users for suggestions on improving the calibration lamp  
system on the telescope, e.g., flux, wavelength distribution, emission- 
line calibration, etc., and report at the next meeting.


CIF plans for next year - Hawley, Klaene:

The major CIF project for next year is the direct-drive replacement  
for the alt and az telescope axes.  There may be time and resources  
for other smaller projects (e.g., cal lamps, as above) and minor  
upgrades.  Suzanne encourages the Users Committee members to talk with  
their users about telescope and instrument upgrades.  There is some  
"opportunity space" here, particularly for instrumentation upgrades.


Science highlights due - Hawley:

For those institutions that have not submitted their annual science  
highlights to Suzanne and Bruce, the window for acceptance is rapidly  



[open from previous months]:

ACTION:  Committee members should send one or two science highlights  
from the telescope users from their institutions to Suzanne (slh at and Bruce (gillespi at not later  
than 1 October for use in the Annual Report to the ARC Board of  
Governors meeting in November.

STATUS:  A few institutions have not yet turned in their highlights.

[new actions from this month]:

ACTION: The Users Committee representatives are to ask their  
respective users for suggestions on improving the calibration lamp  
system on the telescope, e.g., flux, wavelength distribution, emission- 
line calibration, etc., and report at the next meeting.


Next meeting:

The next Users Committee phonecon will be on Monday, 3 November, 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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