[Previous] | [Session 12] | [Next]
E.J. O'Neil, G. Schneider, A.J. Ferro, W.P. Hubbard, M.I. Barg, E.B. Stobie, R.I. Thompson (Steward Obs., Univ. of Az.), Torsten Boeker, S.T. Holfeltz, L.D. Petro (STScI)
During Servicing Mission 3B for the Hubble Space Telescope, a reverse-Brayton cycle turbine cooler will be installed in conjunction with a new external radiator to recool the Near Infrared Camera Multi-Object Spectrometer's (NICMOS) MgCdTe focal plane arrays to operational temperatures of approximately 75K. The new NICMOS Cooling System (NCS) will circulate cold Neon gas through the cooling coils in the NICMOS cryostat (originally used to freeze out the now depleted solid Nitrogen cryogen). Today, NICMOS remains passively functional, and should return to full usability with all observing modes intact with the advent of the NCS. Here, we report on the expectations for the performance of NICMOS once integrated with and cooled by the NCS based on an extensive series of flight and ground experiments and our experience with flight spare detectors operated at these temperatures. We discuss the results from the shuttle-born HOST mission, laboratory experiments at the Steward Observatory NICMOS detector Laboratory emulating the on-orbit warm-up of the detectors, and system level and electro-magnetic susceptibility and interference tests at the Goddard Space Flight Center. From these, and our experience with the NICMOS both during its pre-launch testing and calibration, and on-orbit use during HST Cycle 7, we re-evaluate expectations for systemic read-noise, dark currents, thermal backgrounds, quantum efficiencies, and optical and mechanical stability of the instrument platform. We discuss the expected changes in these characteristics, with respect to HST Cycle 7, both in terms of established performance metrics and their effects on the formulation and conduction of effective observational strategies for conducting NICMOS science observations. This work is supported, in part, by NASA grant NAG5-3042 to the NICMOS Instrument Definition Team.
If you would like more information about this abstract, please follow the link to http://nicmosis.as.arizona.edu:8000/NCC_EMI_2000/EMI2000.html. This link was provided by the author. When you follow it, you will leave the Web site for this meeting; to return, you should use the Back comand on your browser.
The author(s) of this abstract have provided an email address for comments about the abstract: gschneider@as.arizona.edu