Optical testing of XMM flight model mirror module I and II at the vertical EUV/X facility

The x-ray multi-mirror mission is one of the four 'cornerstone' projects in the ESA Long-Term Programme for Space Science. The image quality of two complete flight telescopes has been evaluated in a facility whose vertical optical axis minimizes deformation induced by gravity. The specimens illuminated by an EUV (58.4 nm) collimated beam allows the measurement of the point spread function, and the effective area across the field of view. Additionally, an x- ray pencil beam (1.5 and 8 keV) was used to measure the reflectivity on selected shells. The optical performance of the two first XMM flight telescopes was assessed during an environmental test campaign. The impact of the the thermal and vibration tests is presented and the performance of the two telescopes are compared.