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arXiv · 1207.3329

Using ACIS on the Chandra X-ray Observatory as a particle radiation monitor II

C. E. Grant·P. G. Ford·M. W. Bautz·S. L. O'Dell
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Abstract

The Advanced CCD Imaging Spectrometer is an instrument on the Chandra X-ray Observatory. CCDs are vulnerable to radiation damage, particularly by soft protons in the radiation belts and solar storms. The Chandra team has implemented procedures to protect ACIS during high-radiation events including autonomous protection triggered by an on-board radiation monitor. Elevated temperatures have reduced the effectiveness of the on-board monitor. The ACIS team has developed an algorithm which uses data from the CCDs themselves to detect periods of high radiation and a flight software patch to apply this algorithm is currently active on-board the instrument. In this paper, we explore the ACIS response to particle radiation through comparisons to a number of external measures of the radiation environment. We hope to better understand the efficiency of the algorithm as a function of the flux and spectrum of the particles and the time-profile of the radiation event.

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C. E. Grant, P. G. Ford, M. W. Bautz, S. L. O'Dell. 2012-07-13. Using ACIS on the Chandra X-ray Observatory as a particle radiation monitor II. https://doi.org/10.1117/12.925467

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