Comparison of various models of Monte Carlo geant 4 code in simulations of prompt gamma production

In this paper, results of simulations of the gamma-ray production in reactions with 70 MeV protons in a target of PMMA are presented. The data obtained by means of two versions of Geant 4 software, 9.3 and 10.01, have shown significant differences in the gamma-ray spectra. The comparison between the calculated spectra and the measured ones has been carried out. The tested versions do not give satisfactory agreement with the experimental result. The reason of the performed verification was the planned application of this simulation toolkit for the preparation of in vivo dosimetry based on the prompt gamma-ray measurements for the proton therapy.