52: Assessment and improvements of Geant4 models in the context of prompt-gamma hadrontherapy monitoring

Purpose: The utilization of protons and carbon ions for radiotherapy purposes provides high conformity and increased biological effectiveness. In order to fully benefit from the advantages, a precise beam range monitoring in real time is vital. The detection of prompt gammas with a collimated scintillating detector makes it possible to locate the Bragg peak position during proton or carbon ion irradiation. Accurate Monte Carlo simulations are essential both for the further development of an optimized detection array and for the accurate estimation of the applicability of the system in clinical conditions. Purpose of the current work is to assess and improve the performance of the Geant4 toolkit in the description of currently available prompt-gamma data.