For large space missions maximizing the time spent observing science targets by minimizing overhead increases the scientific return of the mission. On the James Webb Space Telescope (JWST), the baseline mode of resetting the near infrared detectors is a pixel-by-pixel reset. For the Hawaii-2RG detectors this requires 10.5 seconds. Over the life of the mission, 2-3% of the total time is spent performing these resets. In this paper, we investigate using the much faster row-by- row reset mode of the Hawaii-2RG as an alternative. Resets in this mode can be performed in only 40 milliseconds allowing more time for science. We investigate how the changing of the reset modes affects: thermal stability of the detectors, total noise, and observed persistence after bright sources are observed. Overall, any negative side effects seem to be outweighed by the increase in the available exposure time for science during the lifetime of JWST.

Date Published: 28 August 2014
PDF: 9 pages
Proc. SPIE 9143, Space Telescopes and Instrumentation 2014: Optical, Infrared, and Millimeter Wave, 91433U (28 August 2014); doi: 10.1117/12.2059825

Published in SPIE Proceedings Vol. 9143:
Space Telescopes and Instrumentation 2014: Optical, Infrared, and Millimeter Wave
Jacobus M. Oschmann Jr.; Mark Clampin; Giovanni G. Fazio; Howard A. MacEwen, Editor(s)