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Measurements with the Chandra X-Ray Observatory's flight contamination monitor

R. F. Elsner·J. J. Kolodziejczak·S. L. O'Dell·D. A. Swartz·A. F. Tennant·M. C. Weisskopf
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Abstract

NASA's Chandra X-ray Observatory includes a Flight Contamination Monitor (FCM), a system of 16 radioactive calibration sources mounted to the inside of the Observatory's forward contamination cover. The purpose of the FCM is to verify the ground-to-orbit transfer of the Chandra flux scale, through comparison of data acquired during the ground calibration with those obtained in orbit, immediately prior to opening the Observatory's sun-shade door. Here we report results of these measurements, which place limits on the change in mirror--detector system response and, hence, on any accumulation of molecular contamination on the mirrors' iridium-coated surfaces.

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R. F. Elsner, J. J. Kolodziejczak, S. L. O'Dell, D. A. Swartz, A. F. Tennant, M. C. Weisskopf. 2000-04-11. Measurements with the Chandra X-Ray Observatory's flight contamination monitor. https://doi.org/10.1117/12.391600

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