Science highlights, calibration, and performance of EPIC on Newton-XMM: the MOS cameras.

EPIC, on the Newton Observatory, comprises three CCD cameras that provide spectroscopic imaging over the band 0.1-12 keV, with full coverage of the 30' diameter field of view of the three telescopes. The combination of bandwidth, throughput, and spectral resolution, has produced many interesting observations in more than two years of operation. These range from stars, normal, and neutron, SNR & Pulsars, via galaxies, to clusters of galaxies and the most distant quasars. Some of the latest results will be presented. A few days' operation on orbit provides more instrument performance data that can be gathered in the most thorough ground calibration, and many new facets of the instrument performance become evident in orbit. The high throughput of the Newton telescopes provides images and spectra of high statistical precision. This puts an additional burden on the calibration, and there has been much progress by the EPIC team in defining a precise and accurate calibration at the few percent level. The EPIC MOS CCDs perform well in orbit and show considerable radiation hardness against soft protons, due to their peculiar architecture. The degradation of spectral resolution, due to radiation damage, is dominated by hard solar flare protons. At present, this is within the predicted limits and the good spectral performance of EPIC is maintained.