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4.5.4 Radiation Damage Modeling

Radiation damage in flight is expected to degrade the CTI performance of the CCD chips with time. Fig. 4.18-4.20 illustrate the predicted effect on a simulated astronomical spectrum with emission lines. The radiation damage estimate is based on a 95% worst case limit over five years, on data for a radiation model done by SAIC for NASA Headquarters. Fig. 4.18 shows an undamaged chip. The next two cases show the predicted spectrum for shields of 8 cm and 4 cm thicknesses.

John Nousek