Optimization of Beam Scattering System for IFJ PAN Proton Radiotherapy Facility by Monte Carlo Simulations

The work is aimed at optimizing the 60 MeV proton beam spreading system at the IFJ PAN radiotherapy facility for the treatment of ocular melanoma tumors. Single scattering foil and double scattering foil systems have been investigated by Monte Carlo simulations. In the case of the single scattering foil system dose distributions were uniform to within ± 1 % over a 4-cm-diameter region, whereas in the case of the double scattering foil system the same uniformity was achieved in a region up to 3.6 cm in diameter, but its efficiency of dose rates was 5.7 times better. Since the total thickness of foils in the single and the double foil systems was equivalent, in both cases the energy loss of protons was approximately the same.