Subject: Minutes of June 8, 1998 User's Committee Meeting

From: strauss@astro.Princeton.EDU

Submitted: Tue, 9 Jun 1998 09:36:41 -0400 (EDT)

Message number: 282 (previous: 281, next: 283 up: Index)

	Apache Point Observatory 3.5m User's Committee Meeting
****************April 8, 1998**********************

Attending: Michael Strauss, Bruce Gillespie, Ed Turner, Jeff Brown,
Chris Stubbs, Alan Uomoto

Missing: Rene Walterbos, Ed Kibblewhite

  Status of secondary polishing
  Recent visitor instruments
  Tertiary rotation
  Recruitment status
  Status of Echelle
  The night from hell

  *********Status of Secondary*****
Uomoto: The secondary is leaving Swales with its polishing cell on
Friday; arriving in Tucson w/ polishing cell on Monday, June 15.
Schedule for starting polishing not yet clear.   But we are holding
our place in the queue. The schedule is for them to finish polishing
6-18 months after they receive the mirror. 
  There has been a delay of shipping, on request of Steward, just
because they didn't have floor space for it yet.  They say they are ready
for it now.
  There is some concern about our being ready to integrate the finished mirror
into the telescope, could be in early 1999.  We need some planning for
this, possibly including the ability to do tip-tilt at 10 Hz or so.

  ***********Recent Visitor Instruments***********
  Stubbs: Bruce Woodgate et al at Goddard has built a Fabry-Perot
imaging instrument.  This instrument has been on the telescope in the
past; it has returned to APO, and had its first recent run on the
telescope.  Integrated well with telescope.  Camera system looks a lot
like SPICAM (2048^2 SITE chip, although only the central 1K^2 is
illuminated).  The front-end F-P filter is somewhat more complicated.
The idea is that this instrument will live at APO (although
occasionally traveling to other telescopes).  Resolution is 350 km/s
at H alpha, which is fairly broad as F-P's go; we could imagine buying
some more narrow etalons in the future.  It is sufficiently
idiosyncratic that you really need to collaborate with the Goddard
folks to use it; we'll see what happens down the line. There is as yet
no manual for this instrument, and is not yet very user-friendly (and
definitely not usable remotely yet!).  It also requires of order 3-4
hours of calibrating per day (mostly daytime), etc.  But people are
excited about it.

Uomoto: We are thinking about building an imaging instrument with a
ramp filter; not nearly as narrow as a F-P, but it would have quite a
bit higher throughput.

Gillespie: An 1-5 micron imaging 1K^2 Aladdin array is coming to the
mountain for commissioning, built by Sean Casey now at Moffet, but most
recently at GSFC.  He is collaborating with Kibblewhite (who may be
interested in using this with ChAOS).

*************Rotation of Tertiary Mirror**************
Stubbs: Stubbs et al. have started detailed planning and design for
this.  Should be much more robust and repeatable than the current
system; the pointing model is found to vary quite a bit when one
returns to nominally the same place.  Initial implementation will be
manual, not automatic.  More work to allow this to happen at any
altitude at the telescope.  Timescale is something like 6 months to
get this going.  The spec we're shooting for: 5 minutes to rotate from
one instrument gathering photons to the next.

Gillespie: Camron Hasting has been engaged to work as an observing
specialist this summer; he has already successfully solo'd for several
nights. We might think about doing this in the future as well; having
people come in every summer to give the full-time observing specialist
to have a break.
  We have enough people to cover us until the shutdown, but are
continuing to recruit to have full contingent of permanent Observing
Specialist staff by August (i.e., three FTEs).

Turner: Much communication between APO and Chicago.  The original plan
was to ship the instrument in mid-June; this will not happen.
Delivery of second half of July is probably realistic.  They will come
out the week of June 22 to plan the arrival of the instrument in detail.

Brown: They say that the instrument will not be available for general
users in the 3rd quarter, as they will still be in commissioning.

  *************The night from hell****************
There was a night a week or so ago when *everything* went wrong (see
With heroic effort, the next night was fine, but Gillespie said that we
don't have a clear idea of what all went wrong; a night to remind us
that we still have some poorly understood telecommunication instabilities
in the system that occasionally become manifest and recover without
clearly understood intervention.

  Last month's minutes are approved.

  Next meeting, Monday, July 13, 12:30 PM

APO APO APO APO APO  Apache Point Observatory 3.5m  APO APO APO
APO  This is message 282 in the apo35-general archive. You can find
APO  the archive on
APO  To join/leave the list, send mail to
APO  To post a message, mail it to