Subject: 3.5-m Users Committee minutes 11/03/08

From: Bruce Gillespie

Submitted: Mon, 10 Nov 2008 22:34:28 -0700

Message number: 1117 (previous: 1116, next: 1118 up: Index)

             APO 3.5-m Users Committee Phonecon, 11/03/08

Attending:  Suzanne Hawley, Bruce Gillespie, Scott Anderson, Al  
Harper, Meredith Drosback (for Remy Indebetouw), Mark Klaene, Bill  
Ketzeback, John Bally, Rene Walterbos, and Michael Strauss

Absent: Jon Holtzman, Jon Fulbright

Minutes taken by Bruce Gillespie


User feedback, comments from institutional representatives:

Princeton (Michael Strauss) - Michael said that the PU users have been  
happy with their early experiences using TripleSpec.

Colorado (John Bally) - John is presently at APO hosting a CU student  
field trip.  Regarding NIC-FPS, he suggested that we should  
standardize the instrument's focus script by limiting Fowler sampling  
to 0 or 1 (to save time), and that bright stars should be used for  
focussing with a narrow-band filter (to minimize persistent image  
problems inherent to the detector).  The persistent images, which  
appear as negative relative signal, take a long time and many flushes  
to remove them.  Al Harper reported that he has recently looked at NIC- 
FPS images, and sees latent images as positive, too--he will send an  
example to John Bally.  Suzanne asked Mark to discuss the suggestion  
of standardizing NIC-FPS focussing procedures with the Observing  

Chicago (Al Harper) - Al had no further comments on user feedback.

NMSU (Rene Walterbos) - Rene reported that the spectrograph focus of  
DIS is recently noticeably worse than it has been earlier in the year;  
this is particularly detrimental to radial velocity measurements.   
Several weeks ago, Russet McMillan and Jon Holtzman recently adjusted  
the DIS focus, as we routinely do seasonally.  Mark said that Russet  
then rechecked the DIS focus yesterday, and found that it needed a  
significant readjustment that improved the resolution by a factor of  
~2.  This is surprising, and may be related to the recent spate of  
warm weather we have been having.  Suzanne said that DIS  
spectrographic focus should be properly maintained for all users, not  
just for programs requiring the best resolution.  She asked Mark to  
look into the feasibility of making a monthly check and adjustment of  
DIS spectrographic focus, rather than quarterly.

Washington (Scott Anderson) - Scott mentioned that Agile users are  
reporting frequent network disconnections, which interrupts the data  
reads in high-speed observing scripts.  During a disconnection, the  
software repeatedly tries to reconnect, which to the APO system looks  
like a hacking attack.  The APO software then denies the requests from  
the remote user, which exacerbates the situation.  As a temporary fix,  
Fritz Stauffer has adjusted the parameters for access denials, but a  
better solution will come when Agile is run under TUI; TUI will allow  
that data collection to continue during network disconnections.

Virginia (Meredith Drosback) - nothing to report.

Johns Hopkins (Jon Fulbright) - no report.


Discussion of telescope/instruments report - Klaene:

Mark summarized the report, noting the recent good weather and  
relatively trouble-free telescope and instrument performance.  There  
have been minor bugs in the software controlling the NA2 instrument  
rotator, and some of the motion-control parameters for the tertiary  
mirror have been tweaked.  The cranky DIS-blue ion pump is being  
watched, and we may choose to replace it during an upcoming spell of  
bad weather.  The recent work and repairs to TripleSpec have been  
completed, and the Agile move to the TR2 port is underway, although we  
have had some problems with motor torque with the new image rotator.   
The APOLLO lunar-ranging program has been running well, and the plan  
for next year's CIF projects is being finalized.


3.5-m Telescope, Instruments, and CIF Projects Highlights, 10/2/08  
through 10/28/08

                                Mark Klaene

0) Overview

Under mostly clear night skies, the telescope has been working quite  
well during the period.  Minor NA2 rotator problems have caused small  
losses in observing time.  The new boiler for lower dorm is complete  
and the new site-wide fire alarm system is receiving its final  

1) Telescope

New power supplies were installed to address the axial stepper motor  
noise and seemed to have helped, although occasional on-full-step- 
error's are still being seen.  The instrument rotator for the TR2 port  
is being installed this week, and tuning will be done on its servo  
loop once it is installed.  Axis controller software continues to be  
refined on the NA2 rotator axis.

We saw our first freeze for this season, which caused a problem with  
the DIS slitviewer shutter.  The system has since been winterized by  
installing insulation around the camera.  This shutter has shown cold  
temperature problems in previous years and replacement units do not  
seem to help, while the installation of thermal insulation seemed to  
fix the problem last year.

2) Instruments

The DIS-blue ion pump is occasionally running high and the dewar may  
need to be opened up in the future for servicing--spare ion pumps are  
now on site.  DIS-red and SPIcam are fully operational with no problems.

Echelle and NIC-FPS both continue to be operational with no problems.   
We are still waiting for UVa to design and build up a new NIC-FPS fan- 
out board that will hopefully address the residual readout noise.

TripleSpec warmup, gauge replacement and ion pump installation are now  
complete.  The instrument is cold and fully operational.

Agile is still available at NA2; it will be moved to the TR2 port once  
the new rotator is fully tested.  TUI integration for Agile  
continues.  Agile spares procurement and documentation updates are  
also in progress.

GFP is currently warm because it is not scheduled for observing until  
late November.

APOLLO remains operational with more record-breaking amounts of lunar- 
return photons.  A high-precision gravimeter (needed by APOLLO to  
determine the exact position of the telescope) is slated for arrival  
late in November, and plans are in progress to install it at the 3.5-m.

3) CIF projects

Planning for next year's CIF projects is well underway.  The principal  
projects are direct drives for Az and altitude axes, new axis  
controllers for az and alt, and cal lamp upgrades.


Calibration (Flat, Arc lamps) upgrades - group:

Suzanne said that as part of the CIF plan for next year, we are  
considering various improvements to the on-telescope calibration lamps  
system.  We would like to hear suggestions from the users.  Rene asked  
if one upgrade would be to get an arc lamp with more lines in the  
blue.  Suzanne said yes, and also for a flat-field source with more  
flux in the blue and ultraviolet.  Scott said that he asked and got no  
replies from the UW users.  In any case, Suzanne said that we will do  
something that improves the line density and flat-field flux in the  
blue, now that we have improved DIS sensitivity in that wavelength  
region.  She asked if anyone knew if better calibration sources were  
needed for NIC-FPS.  John Bally said that NIC-FPS users generally use  
OH emission in the night sky for calibration.  In closing the topic,  
Suzanne asked that users give us their suggestions for improving the  
calibration lamps system; this opportunity will only stay open over  
the next few months.


Autofocus status - Klaene:

Mark pointed out that autofocus has been a project worked on this past  
year.  Using the NA2 guider to sense changes in focus, the system has  
been prototyped and works reasonably well, but work is still needed to  
characterize and improve it.  Users can ask the Observing Specialists  
to turn the system on during their observing programs, and feedback is  
welcome.  Suzanne added that the principal use of the autofocus system  
is to keep targets in focus during DIS observations--we will need to  
implement autofocus differently for TripleSpec and SPIcam.  One  
consequence of the system is that it is OK to guide on field stars  
using autofocus.  We will soon have user information on autofocus on  
our web pages.


Communication with users during observing - Hawley:

Suzanne remarked that some users find the TUI message window  
inadequate for enabling easy communication with the Observing  
Specialists during remote observing runs.  Over the years, several  
Observing Specialists have opposed the introduction of a live A/V link  
to the control room, but it seems reasonable to consider the use of  
live audio, such as iChat or Skype, to facilitate user-ObsSpec voice  
communication.  Bill pointed out that the link might need to be muted  
most of the time, to avoid a dueling of the music played at the  
respective ends of the hookup.  The message window does have the  
advantage of being logged, but it could still be used for purposes  
requiring an archive record, and for instances of cut-and-paste  
communications.  Suzanne said that the site will look into  
implementing a trial version of live audio, probably Skype, between  
users and the 3.5-m's control room.


Future instrumentation (priorities for replacements, upgrades) - Hawley:

Suzanne announced that we will have an opportunity beginning in 2010  
to provide some financial support for the development of new and  
upgraded instrumentation for the 3.5-m telescope.  When the 2009 CIF  
projects are completed, instrumentation and their upgrades will be the  
higher priority for CIF funds.  Specifically, both the echelle and  
SPIcam are probably nearing the end of their useful lives in their  
current configuration, and both instruments have seen dwindling user  
demand in the past few years.  In order to get the next-generation  
instruments on the telescope, we need both user involvement and  
leadership--if someone in the ARC user community wants to step forward  
and take on the PI role of defining and developing new instrumentation  
for the telescope, funding can be made available.  Suzanne will take  
this proposal to the ARC Board of Governors in two weeks, and she  
would be interested in hearing any user feedback both before and after  
the Board meeting (slh at


3.5-m publications list update - Walterbos:

Rene compiles the list of new publications and theses based on 3.5-m  
data annually for the ARC Board meeting.  He asks that the Users  
Committee members remind their users to send him listings of all  
publication and theses from the period Oct. 07 through Oct. 08 ( 



[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:  Completed.

[new actions from last 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.

STATUS:  Discussed with Users Committee 11/3.


Next meeting: The next Users Committee phonecon will be on Monday, 8  
December, 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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