Efficiency of segmented HPGe γ-ray detectors: design criteria for pulse shape analysis

The problems of the reconstruction of the trajectory of γ-rays and of the identification of their interaction points in segmented HpGe detectors are discussed in view of their importance in the design of the next generation of detector arrays for γ-ray spectroscopy studies. In fact, the level of tracking of the γ-ray interactions in the medium controls the overall detection efficiency. Tracking algorithms taking into accounts the detection segmentation together with the pulse shape analysis have been developed making use of the GEANT simulation package. The present work focuses on two main points. One is how to disentangle the pulse shape analysis effects and investigate their possibilities, the other is the study of the consequences that different types of segmentation have on the overall efficiency. Two geometries have been chosen, that of a single cylindrical detector and a spherical shell