Focal plane detectors of a Laue lens telescope for nuclear astrophysics

Descripció del recurs: el 01 setembre 2012Gamma-ray astrophysics in the energy range of nuclear transitions (from a few hundred keV to a few MeV) has an extraordinary potential for understanding the evolving and violent Universe. In spite of the strong e orts accomplished by past and current instruments in order to perform observations in this energy range, an improvement in sensitivity over present technologies is needed to take full advantage of the scienti c potential contained in this energy range. In response to this desire, the gamma-ray lens concept based on Laue di raction was presented as a solid alternative. Its feasibility was demonstrated in the CLAIRE project, where ground and balloon-borne experiments with a Laue lens prototype were accomplished. The successful results of these and others R&D activities have pushed gamma-ray lens technology on the road towards a space mission. This work deals mainly with the focal plane detector of a Laue lens telescope, and the results of a long distance test performed with the gamma-ray lens CLAIRE are also presented. Our main research has evolved in the framework of two missions concept studies -GRI (2007) and DUAL (2010)- submitted to the ESA Calls for a Medium-size mission opportunity in the Cosmic Vision 2015-2025 programme. As far as the GRI mission is concerned, a focal plane detector con guration based on CdTe pixelated detectors is proposed, whilst development and testing of a detector prototype are accomplished. As for the DUAL mis- sion, simulations of the expected space radiation environment and the resulting detector activation are carried out in order to estimate the performances of the mission. Beyond the detector technology proposed in GRI and DUAL, a wide variety of technologies could be explored for the focal plane of a gamma-ray lens mission as well as for a stand-alone detector; a focal plane detector based on liquid xenon is also considered