Calibration Access and Data Handbook

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Generation from In-Orbit Data

The degradation correction coefficients have been calculated by a linear fitting to the measured counts (coincidence loss corrected) of the stars BPM 16274, Hz 2 and GD 153 observed periodically since the beginning of the mission. The fit is done for each filter as a function of the MJD of observation, using the data of all stars. These stars are observed once per year (BPM 16274 twice) to monitor the variation of sensitivity.

Michael Smith 2011-09-20