NICMOS Temperature Monitoring
نویسندگان
چکیده
The NICMOS detectors are sensitive to the operating temperature. During the Cycle 7 era, NICMOS was cooled through cryogenic solid nitrogen. This resulted in an operating temperature varying from 61K to 62.5K before the nitrogen was exhausted. Using the new NICMOS Cooling System (NCS), the nominal temperature is significantly more stable, but at a higher temperature, 77.15 K. The stability of the dewar temperature is maintained through manual changes to the NCS temperature set-point. The achieved thermal stability is ∼0.1K. We describe the temperature history, the NICMOS temperature dependencies and remaining temperature fluctuations.
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