Gamma spectrum and coincidence summation simulations with Geant4 in the analysis of radionuclide using BEGe detector

A Geant4 application has been developed to simulate the gamma spectrum of a BEGe detector. The summation effects were encompassed for both random and true coincidences through a time-based approach. The application well reproduces the typical spectral features such as full energy peaks, escape peaks, summation peaks and Compton/backscatter continuum. The simulated gamma response is consistent with empirical data within 3%, while simulations of the X-ray and baseline regions are valid within a 10% deviation.