Evidence for micrometeroid damage in the pn-CCD camera system aboard XMM-Newton

Abstract

The mirror systems of the X-ray observatory XMM-Newton were designed to image X-rays up to 15 keV by grazing incidence reflection onto a focal plane, equipped with Charge Coupled Devices (CCDs). In orbit #156 we have observed a sudden increase of about 35 "bright" pixels spread over 15 cm2 in the pn-CCD camera system. The amount of locally generated leakage current cannot be explained by ionizing particles. We suggest that a micrometeroid scattered under a small angle off the X-ray telescope mirror surface finally reached the focal plane detector and produced the damage.