Dependence of the depth-dose distributions and ranges of proton beams in water medium on Geant4 parameters

The aim of this work is to investigate the influence of the Geant4 parameters on the range and the depth-dose distribution (Bragg curve) of proton beams with incident energies of 90, 150 and 230 MeV injected upon a water medium, using the Geant4 simulation package. The simulated Bragg peak ranges and the depth-dose profiles have been compared with the ones obtained from the National Institute of Standards and Technology and the experiments, respectively. It has been seen that the Geant4 parameters, such as the step size and production cuts, under study have non-negligible effects on the range and the depth-dose distribution of incident proton energies of interest, especially at 150 and 230 MeV.