The mirror module design for the cryogenic x-ray imaging spectrometer on-board ORIGIN

ORIGIN is a medium size high-energy mission concept submitted to ESA in response to the Cosmic Vision call issued on July 2010. The mission will investigate the evolution of the Universe by performing soft X-ray high resolution spectroscopic measurements of metals formed in different astrophysical environments, from the first population III stars at z > 7 to the present large scale structures.

The main instrument on-board ORIGIN will be a large format array of TES X-ray micro-calorimeters covering a FOV of 30' at the focal plane of a grazing incidence optical module with a focal length of 2.5 m and an angular resolution of 30" HEW at 1 keV. We present the optical module design which is based on hybrid technologies, namely Silicon Pore Optics for the outer section and Ni electro-forming for the inner section, and we present the expected performances based on test measurements and ray-tracing simulations.