Optimisation of a hybrid photoneutron source in a linear accelerator using GEANT4 and MCNPX Monte Carlo codes

Radiotherapy is important for treating oral cancer in advanced stages. Boron neutron capture therapy represents a unique modality in which neutron beams penetrate into the tissue within an epithermal range. Different methods are available for neutron production, and in this study, we used an electron accelerator. A photoneutron source based on three different energy values (10, 25, and 50 MeV) of a linear accelerator electron beam was designed using GEANT4 (GEometry ANd Tracking) and MCNPX (Monte Carlo N-Particle eXtended) simulation codes. The results indicate that a hybrid photoneutron source introduced tungsten and uranium with BeO. The statistical uncertainties in all simulations were less than 0.3 and 0.07% for MCNPX and the standard electromagnetic physics packages of GEANT4, respectively. Various cross-sectional and stopping-power data and different physics simulations produced different distributions.