Apache Point Observatory 3.5m User's Committee Meeting January 11, 1999 Attending: Ed Turner, Jeff Brown, Bruce Gillespie, Chris Stubbs, Alan Uomoto, Rene Walterbos. Not attending: Ed Kibblewhite, Michael Strauss Agenda: Echelle status New 2ndary report Tertiary rotation project Top-end enhancements, wind shake? SDSS science synergy *************Echelle status************* Echelle commissioning proceeds with good progress and no very serious problems so far. Stellar spectra have been obtained, and many performance parameters of the instrument have been ascertained to first order (see Don York's message in apo35-general, dated 11 January 99). Work continues on instrument alignment and telescope collimation/pointing, and the remote interface is continuing to be wrung out. Science commissioning will continue through January and February, and user and engineering documentation will be delivered. We still expect the instrument will be available for scheduled science use by the general ARC community for the 2nd quarter. *************New 2ndary report************* Alan Uomoto: There has been little news in the past month, other than a delivery in January would be "difficult," and "possible" in February--we should use 31 January as the rough planning date for delivery. Alan is planning a trip to the Steward Observatory Mirror Lab in the near future, and the details of mirror acceptance and delivery need to be worked out. Jon Davis is designing, and having built, the necessary parts to mount the new mirror when it arrives or soon thereafter. *************Tertiary rotation project************* Chris Stubbs: The design is done and the fabrication is underway, expected complete by mid-February and installed on the telescope in late February. Need a 7-day shutdown which would pre-empt scheduled science with ~two-week warning. There followed some group discussion about permanently mounting other instruments on the telescope, once semi-automated tertiary rotation is completed. This will usually require a new rotator and guider, costing an estimated $50k per port. We will consider the budgetary angle on doing this, port by port, over the next few years. *************Top-end enhancements, wind shake?************* Ed Kibblewhite is heading up a design for major enhancements to the 2ndary support structures and top-end truss, as detailed in the previous Users' Committee minutes. No report available at this time. There are recent observer reports of significant wind shake, and the group wondered if something in the 2ndary support structures has come loose or broken. Jon Davis inspected the 2ndary mechanicals and found nothing amiss, apart from a loose bolt which he believes would not contribute to wind shake. The bolt was tightened and we are looking for further occurrences of the purported problem. *************SDSS science synergy************* Given the recent and dramatic examples of SDSS discovery science which is supplemented by follow-up 3.5-m observations, the group discussed the need to provide more formal and expeditious 3.5-m opportunities to SDSS researchers. Apart from the institutional conflicts, it was decided that the current ad hoc system of applying for 3.5-m time in the usual way is sufficient for now, and also that DD time could be requested to provide 3.5-m observations in support of SDSS on relatively short notice, when needed. A more formal mechanism for this is not foreseen as necessary, at least not anytime soon. **************************************** Last month's minutes are approved. --NOTE NEW TIME FOR NEXT MEETING-- Next meeting, Monday, February 8, 1999, 12:00 noon Eastern Time APO APO APO APO APO Apache Point Observatory 3.5m APO APO APO APO APO This is message 333 in the apo35-general archive. You can find APO the archive on http://www.astro.princeton.edu/APO/apo35-general/INDEX.html APO To join/leave the list, send mail to apo35-request@astro.princeton.edu APO To post a message, mail it to apo35-general@astro.princeton.edu APO APO APO APO APO APO APO APO APO APO APO APO APO APO APO APO APO