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ACIS CCD Sensitivity to Ionizing and Non-Ionizing Radiation

Preliminary radiation damage tests of ACIS front illuminated CCDs have been performed with two types of ionizing radiation sources. The Fe-55 X-ray source is expected to produce damage in the oxide layer and bulk oxide interface causing increased surface dark current and flat band voltage shifts. Because of the anticipated exceptional focusing of the HRMA this type of test is pertinent to the issue of overexposure and "burn-in" caused by bright X-ray sources. The high energy proton beam at the Harvard Cyclotron represents a class of radiation that primarily cause damage through collisions with silicon atoms. This displacement damage can result in trapping centers resulting in increased CTI and bulk dark current.



 

Please address comments and questions to Dr. John Nousek ( nousek@astro.psu.edu )