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WIYN Project Report (1Mar96) (from KPNO, NOAO Newsletter No. 45, March 1996) The WIYN Project, the entity formed to construct and commission the WIYN Observatory, continues to march steadily towards a formal conclusion sometime during spring 1996. Residual Project responsibilities include completing delivery of the Instrument Adaptor Sub-system (IAS), conducting an Operations Readiness Review (ORR), and completing a variety of Project close-out tasks. IAS installation and commissioning has been mostly completed. The IAS has been in regular use since September 1995. Only one significant problem has been uncovered during IAS commissioning: the stages used to position the guide probe assemblies "stall" when run at too high a speed. Currently, the allowable probe speeds are a factor of 4-8 times slower than our original goal. This has the obvious effect of decreasing observing efficiency when acquiring new guide stars, although at worst the increased overhead is several minutes. As we did not see this problem when lab testing the IAS, we are trying to diagnose why this is a problem on the telescope, so it can be rectified and the probe speed increased to our original goal. Remaining IAS delivery tasks include installation of the Comparison Lamp Assembly (CLA) and Atmospheric Dispersion Corrector (ADC) lenses and associated control software. Mechanical work on the CLA is completed, but completion of the electrical work has been delayed by the electrical work needed to rectify the secondary limit switch situation. CLA installation and testing should be completed by 1 March 1996. The ADC lenses, originally scheduled for delivery in July 1995, has been delivered in early February 1996. Despite the delivery delay, testing during fabrication suggests that the lenses will be very good. After the lenses are delivered and acceptance tested, they must still be AR-coated, bonded, and installed in their cells, a process requiring several weeks. We hope to install these lenses and test the ADC on-site in early April 1996. This would officially complete delivery of the IAS by the Project. Additional IAS related tasks include implementation of a more efficient, semi-automated wavefront measurement and active optics update process, and implementation of closed-loop focus correction (based on a simple Shack-Hartmann scheme). The IAS already contains all the hardware needed for these tasks. Completion of the more efficient wavefront/AO update pipeline is straightforward and should be done by 1 April 1996. A more efficient pipeline would save at least 30-45 mins every night WIYN is operating. The planned closed-loop focus correction scheme, on the other hand, is more experimental in nature and thus its delivery schedule is uncertain. These tasks will be completed by some combination of Project and Operations resources. The ORR rationale was discussed in the December 1995 NOAO Newsletter No. 44 and will not be repeated here. The ORR was held 1-3 February 1996 in Tucson at NOAO Headquarters. Project close-out activities include organizing and storing Project documentation, transitioning management responsibilities from the Project to the Site Manager, and closing out the financial books. All this should be completed by 1 April 1996, subject to the review and approval of the ORR outcome by the WIYN Board on 1 March 1996. Dave Silva
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