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Infrared Group News: Something Old, Something New...(1Jun93) Something Borrowed, Something Blue (from KPNO, NOAO Newsletter No. 34, 1 June 1993) This is a general update on goings-on in the infrared program over the last several months, and our program plan into fall 1993. In detector R&D, 256 x 256 InSb arrays from Santa Barbara Research Center have been turned on and extensively characterized in laboratory test dewars. A fully operational "science grade" device has been installed and used at the telescope in the Cryogenic Optical Bench. As part of this exercise, a peculiarity in the noise pattern of the device was traced to low level contaminants introduced during post-manufacture storage by the vendor; working closely with SBRC, this was verified and a reliable cure found, which lowered the overall noise level measurably. The R&D team has also turned on a NICMOS 3 HgCdTe array and delivered it to the telescope in IRIM, as noted above. The instrumentation program continues to benefit directly from detector efforts. Following the reappearance of IRIM with its new 256 x 256 array, its former 58 x 62 InSb array was relocated to the spectrometer CRSP. This device is better behaved than CRSP's previous array and has led to performance improvements. The SBRC InSb procurement produced a second 256 x 256 array with enough operable area to be of interest for CRSP, and this device will be installed in late summer. It will deliver 135 rows spatially and a full 256 pixels spectrally. Both CRSP and IRIM are being upgraded with new electronics to run in a workstation environment, familiar to users of SQIID. This will get them off the aging 11/73 systems, which are fast approaching oblivion, and provide much greater power and flexibility for data acquisition and real time analysis. Regarding projects in progress, the electronics upgrade project is called WILDFIRE and will ultimately produce units for five instruments and three telescopes in all. Its first telescope implementation will be in late April at the 1.3-m. Fall 1993 will see the installation and testing of WILDFIRE at all telescopes with facility IR instruments, a not inconsiderable exercise. The high resolution grating spectrometer Phoenix is well along in detailed design, and we will begin to cut metal in May. The major optical components have all been contracted out as well. The Cryogenic Optical Bench, a second generation IR camera emphasizing a great variety of spatial and spectral filtering modes, has been to the telescope most recently with a 256 x 256 SBRC InSb array. This instrument has had some difficulties, including a redesign of a portion of the optics to suppress ghosting. Problems remaining are mostly in achieving acceptably precise control of mechanical moving parts. Following upcoming observing runs to exercise it in high background modes with WILDFIRE, we will do an extensive disassembly this fall to address mechanical issues. We expect it to be available for general use in spring 1994. SQIID, COB, and Phoenix all use closed-cycle cooler systems in place of liquid cryogens. The 1.3-m and 4-m have both been plumbed and commissioned with SQIID, and the 2.1-m is scheduled for cooler installation this fall. Finally, "something blue": the venerable single-channel InSb photometer Blue Toad has been retired from the active instrument list. It went out with a (scientific) bang, a successful observation of a stellar occultation by Uranus in mid-April. As a side benefit, we now know the latitude, longitude, and elevation of the 2.1-m to within a few meters courtesy of NASA and the GPS satellite network. Ron Probst for the IR Group
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