Richard Green
The WIYN SAC and Board assembled for their semi-annual meetings at Indiana University on October 22nd and 23rd. The theme was that the current level of base operations support of the Observatory is now at a successful equilibrium. That success is reflected in performance, reliability, and steady progress on new instrumentation. Continuing attention to the WIYN telescope system has produced a continuing improvement in delivered image quality (DIQ). While the median remains at an impressive 0.8", a DIQ of 0.6" or better is achieved 18% of the time. (For reference, the site-delivered median DIQ is ~0.66"). The 23 Hz oscillation of the secondary mirror support, that could elongate images by as much 0.2", has been completely eliminated by improvements to the damping. Another decrease to the local contribution to image distortion is attributable to improved uniformity of primary mirror temperature, by painstaking sector-by-sector recalibration, and tuning of the thermal control system. Finally, improvements to the focus algorithm and its ultimate automatic implementation will both improve the DIQ and save observational overhead.
Even more impressive is the year's average downtime statistic-—only 2.5% of time that could have been used for observation was lost to failure. This represents a full factor of two reduction from the previous year's value. The main factor is improved robustness in the complex telescope control software. The typical night-to-night figures are actually better yet, since the average was increased by two significant events during the year—a primary mirror support system failure and a required rework of the cable-wrap "maypole" on the azimuth axis.
Meanwhile, progress is being made on new instruments and upgrades. The Mini-Mosaic imager was successfully used in a shared-risk trial in mid-October, and is expected to be fully commissioned and routinely available by January. This imager contains two of the same SITe 2K×4K CCDs as in the NOAO Mosaic Imagers. It will provide larger field of view and better sampling at the imaging port. The WIYN Tip/Tilt Module has made steady progress as well, with most system trades complete and designs moving into the detail stage. Because we had an unfilled Mechanical Engineer position for almost six months, there has been some delay compared to the most optimistic schedule, but we still anticipate full-time use by 2001. In addition, the University of Wisconsin is moving forward with a Cassegrain instrument adapter, which will accommodate Densepak fiber cables without requiring removal of the imager. It should be ready in time to allow imaging while the Instrument Adapter System is off the telescope to be refitted for the WTTM in early 2001.
These improvements are the accomplishments of the many individuals invested in the success of WIYN. Charles Corson has assumed the job of Site Engineer and has been able to devote considerable time to the diagnosis and solution of issues such as the primary mirror thermal non-uniformity and focus. Although the dedicated software engineer, Jeff Lewis, left us earlier this year, Bob Marshall, Shelby Gott, and David Mills have stepped up to understand and substantially improve the control system. As always, the Consortium greatly appreciates the effective efforts of David Sawyer, the WIYN Operations Manager, backed up by Tony Abraham and the KPNO Engineering Team.
The origin of the enhanced effort is the decision by the WIYN Board to increase its annual commitment to the WIYN operations budget. That amount now includes 7.6 FTE of effort, raised from the 6.5 FTE called for in the original agreement, and an additional $100K for capital items and contract efforts. The direct translation of resources into improved performance has been gratifying to the whole Consortium.
Finally, I note a change in NOAO's representation to the WIYN Consortium. Bob Mathieu of the University of Wisconsin has stepped down as Chair of the SAC to become President of the Board. Abi Saha will replace him as SAC Chair. After more than 10 years of service, Caty Pilachowski has stepped down from her role as Board Secretary, to be replaced by Taft Armandroff. The Board noted its gratitude to Caty with the following resolution:
The WIYN Board of Directors, on behalf of the entire Consortium, expresses its gratitude and appreciation for the service contributions of Dr. Caty Pilachowski. Caty was one of the original WIYN negotiators, back in the days when all we had to go on was a mirror blank, some travel money, and dreams of a telescope. It was clear early on that Caty brought a hard-nosed perspective to our deliberations. Her tenure as Board member and Secretary from 1989 to 1999 has been an important contribution. With her departure, WIYN truly loses a major part of its institutional memory. Like the minutes of the preceding Board meetings, one of Caty's essential roles on the Board was to remind us of things we needed to remember, whether pleasant or not. Caty was one of WIYN's indispensable people, and she has left upon WIYN the imprint of her own unique blend of quiet delight and seriousness of purpose. Hopefully, the WIYN Consortium has become mature enough now to survive without her. To quote Caty's own words, although she will no longer be present at our meetings, we should think of her "instead, happily doing science with WIYN data." She has not left WIYN, she is using it!