Efficiency of segmented HPGe detectors: Design criteria for pulse shape analysis

The problems with reconstructing the trajectory of gamma -rays and identify ing their interaction points in segmented coaxial HPGe detectors are discus sed here in view of their importance in the design of the next generation o f detector arrays for gamma -ray spectroscopy Studies. fn fact, the trackin g quality of the gamma -ray interactions in the medium controls the overall detection efficiency. This paper focuses on two main points. One is the st udy of how the tracking reconstruction efficiency is affected by the abilit y of disentangle multiple interactions per segment. The other is the study of the consequences that different types of segmentation have on the overal l efficiency. Two geometries have been chosen: that of a single cylindrical detector and that of a spherical shell.