Computer simulation of an array of Ge detectors for γ-ray imaging

A new generation of instrumentation combining high energy and angular resolutions is required for gamma-ray line astronomy. The development of arrays of small germanium detectors provides the opportunity to use a Ge array as a position sensitive detector which, when coupled with a coded mask, may provide an answer to this necessity. We present an extensive Monte-Carlo simulation study of the influence of the array design on the efficiencies and the feasibility for its use as a position sensitive detector. We also discuss the possibility of using the intrinsic advantages of this type of array detector for the rejection of the beta decay induced background. Finally, as an example, the performance of a complete gamma-ray image: array, veto shield and surronding materials is presented. These results confirm the great promise of this kind of detector for future gamma ray missions.