Monte Carlo EGS5 simulationsof High Purity Germanium (HPGe) detector

High Purity Germanium (HPGe) radiation detectors are widely used for the gamma ray spectroscopy due to their best energy resolution. However, the detector response including Absolute Full Energy Peak (AFEP) efficiency, photo-fraction, Compton-to-photo ratio, etc., depends on the different physical parameters. The main advantage of Monte Carlo simulations lies in the fact that we can separately study the effect of different physical parameters. In this study, we present simulation results of the HPGe detector using Electron Gamma Showers 5 (EGS5) code and compare the simulation results with the already published data. A difference of about 5% was observed when compared with MCNP simulation and experimental results. Finally, optimum value of the Lead shield thickness was determined to be 5 cm for collimator diameter of 12 mm for different energies of interest.