Design of a portable HPGe detector: Performance characterization in identification of medical radioisotopes

摘要

This paper describes the methodology to model a hand-held high purity germanium detector (HPGe) and its performance characteristics. MCNPX was used to model the detector and conduct the study. The detection efficiency and the performance characteristics of the detector were studied over an energy range of 50-550 keV, that covers the energy range of medical isotopes used in nuclear medicine. More specifically, the performance was compared between two common medical isotopes: ~(99m)Tc and ~(131)I. Detector efficiency was calculated for point sources, in air and tissue equivalent material. The maximum source distance at which the detector was able to capture a radiation signal was calculated.