X-ray multi-mirror mission - An overview

The X-ray Multi-Mirror Mission (XMM) is the second cornerstone mission of the ESA Horizon 2000 Science Programme. When launched in late 1999 it will provide a world-class Observatory facility for X-ray astronomers. This paper describes the overall concept of the mission, including the spacecraft bus, the instruments and the innovative replicated optics that produce images of better than 20 arcsecs Half Energy Width, and a total geometric collection area of more than 4500 cm(2). The observatory is unique in that it will provide simultaneously, high throughput non-dispersive spectroscopic imaging (EPIC instrument), medium resolution dispersive spectroscopy (Reflection Grating Spectrometer) and optical/UV imaging and timing from a co-aligned instrument (Optical Monitor). We describe some of the operational aspects and provide a brief description of the scientific potential of the payload.