Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2004 · 24 citations · 0 references
Natural SciencesAstronomyPhysicsAstrophysicsGamma-ray AstronomyOpticsDetector TechnologyGamma-ray Data AnalysisGamma-ray DetectionGamma-ray DetectorsGamma-ray InstrumentationGamma-ray TelescopesAngular ResolutionBalloon-borne Gamma-ray InstrumentsDetectorsGamma-ray Detector TechnologyGamma-ray Telescope DesignLens DesignSpace-based Gamma-ray TelescopesTelescopes
CLAIRE is a balloon-borne experiment dedicated to validating the concept of a diffraction gamma-ray lens. This new concept for high energy telescopes is very promising and could significantly increase sensitivity and angular resolution in nuclear astrophysics. CLAIRE's lens consists of 556 Ge-Si crystals, focusing 170 keV gamma-ray photons onto a 3x3 matrix of HPGe detectors, each detector element being only 1.4x1.4x4 cm<sup>3</sup>. On June 14 2001, CLAIRE was launched by the French Space Agency (CNES)from its balloon base at Gap in the French Alps and was recovered near the Atlantic ocean (500 km to the west) after about 5 hours at float altitude. Pointing accuracy and gondola stabilization allowed us to select 1<sup><i>h</i></sup>12' of "good time intervals" for the data analysis. During this time, 33 diffracted photons have been detected leading to a 3σ detection of the source. Additional measurements made on a ground based 205 meters long test range are also presented. The results of this latter experiment confirm those of the stratospheric flight.