Apache Point Observatory 3.5m User's Committee Meeting February 7, 2000 Attending: Jeff Brown, Jeff Morgan, Rene Walterbos, Ed Turner, Michael Strauss, Bruce Gillespie, Chris Stubbs, Alan Uomoto Absent: Lew Hobbs Agenda: Performance of the optics Status of the guider Observing Specialists Miscellaneous ******************Performance of the Optics************************ Jeff Morgan: The telescope optics are currently capable of routinely delivering seeing of 0.52". There is a sag of the secondary support structure as function of altitude, a bit worse than specs. This induces a coma error of 0.1". We have a plan to correct this sag, so we should soon get 0.45" images (to the extent that the atmosphere gives us such good conditions). At that point, we will be dominated by astigmatism. This is due to mounting problems with the primary, which have been around for a long time (but we're only now properly sensitive to it, due to the new secondary). There may also be damage to one of the flex pivots on the secondary support (which may cause the increased wind-shake problems seen recently). If we can get rid of this problem, we'll have a telescope whose optics can deliver 0.24" images, which is close to the original design spec of the telescope. There are still dynamical problems with the mounts, so the telescope can deliver this kind of image for only a short time (a few seconds). Having said this, people have been seeing truly wonderful seeing in recent weeks, as good as 0.6" in moderately long exposures in the near-IR. **************************The guider******************************* The camera on the autoguider has gone down (see apo35-general #412). With DIS you can guide off the slit viewer manually. But there is no guider capability at the moment with SPICAM or GRIM. There was a glycol leak in the camera head onto the electronics. It was sent back to the manufacturer's twice. When it was first sent back, there were problems with the full-well depth and charge transfer. They haven't yet found the problem, although Jeff thinks the problem is just some improper voltage settings. They will give us some relevant numbers of voltage measurements "as soon as possible". We won't get the camera back before the end of the week, and perhaps somewhat later than that. **************************Observing Specialists*********************** Personnel: We're sad to learn that Karen Loomis has tendered her resignation. We've offered a job again to Camron Hastings, who has accepted. He will start again on 1 April. Eddie Bergeron will come back for two weeks in March to help the current observing specialists and bridge the gap until Camron starts. The 3.5m User's Committee wishes to express its enthusiasm for the tremendous service Karen has given to the observatory over these many years, its regret that she will no longer be working with us, and its best wishes for the new directions she is taking her life. **********************Miscellaneous******************************* Goddard InSb camera: Bernie Rauscher, who was one of the PI's on GRIM, is now at STScI, and is getting involved in this new instrument. There is also a possibility that Goddard may be doing some significant upgrades, including possible Integral Field Unit capabilities and possible automation of such things as filter changes. There was a recent event when an observer called less than 24 hours before their night, saying, "Oh, I've got another observing run on another telescope at the same time; could you please observe the following targets for me?" Please do not assume that the observing specialists are free at a moment's notice to do service observing! We will do service observing for compelling reasons, decided on well beforehand. Even better is to set up scientific collaborations between collaboration astronomers and observing specialists. Work is on-going on the design of the new top-end, with discussions between Stubbs and Kibblewhite underway. Walterbos: A fellow from Rio de Janeiro, Marcos Nunos, with electronics and optics experience, is interested in coming to UW to work on the DIS upgrade, for something like three months. His salary would be covered from his job in Brazil; we would pay for his local expenses (food and lodging). We have both web-based schedules, and hardcopy faxed schedules. We have decided to go entirely with the web-based schedule; let Ed Turner know if this causes any trouble. Postscript files would still be available to download and generate local hardcopies, as they are now. Turner is generating a slight update to the observing request form to clarify which DIS gratings, filters, slits, etc., people actually need. We discussed whether people who have not observed on the telescope for many years should still be considered certified for observing remotely. We have no policy in place of a "statute of limitations", but perhaps should consider one. We discussed this issue, but came to no specific conclusion. Gillespie: We're thinking about the telescope schedule for the rest of the year. At this writing, we don't anticipate any major shutdowns during calendar year 2000. In particular, there will be no shutdown for realuminizing. No corrections to last month's meeting minutes. The next meeting will be held on March 13 at 11:30 AM East Coast Time. APO APO APO APO APO Apache Point Observatory 3.5m APO APO APO APO APO This is message 413 in the apo35-general archive. 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