Pixel detectors for x-ray imaging spectroscopy in space

Abstract

Pixelated semiconductor detectors for X-ray imagingspectroscopy are foreseen as key components of the payload ofvarious future space missions exploring the x-ray sky. Located onthe platform of the new Spectrum-Roentgen-Gamma satellite, theeROSITA (extended Roentgen Survey with an Imaging Telescope Array)instrument will perform an imaging all-sky survey up to an X-rayenergy of 10 keV with unprecedented spectral and angular resolution.The instrument will consist of seven parallel oriented mirrormodules each having its own pnCCD camera in the focus. The satelliteborn X-ray observatory SIMBOL-X will be the first mission to useformation-flying techniques to implement an X-ray telescope with anunprecedented focal length of around 20 m. The detectorinstrumentation consists of separate high- and low energy detectors,a monolithic 128 × 128 DEPFET macropixel array and a pixellatedCdZTe detector respectively, making energy band between 0.5 to 80keV accessible. A similar concept is proposed for the nextgeneration X-ray observatory IXO. Finally, the MIXS (Mercury ImagingX-ray Spectrometer) instrument on the European Mercury explorationmission BepiColombo will use DEPFET macropixel arrays together witha small X-ray telescope to perform a spatially resolved planetaryXRF analysis of Mercury's crust. Here, the mission concepts andtheir scientific targets are briefly discussed, and the resultingrequirements on the detector devices together with theimplementation strategies are shown.