Simulation of Bragg Curves Produced by Protons, Alpha-Particles, and Carbon Ions in Water

Bragg curves for protons, alpha-particles, and carbon ions in water are calculated using the Geant4 software package. The calculation results, which are of interest for practical applications in proton and ion therapy, are compared with experimental data in terms of the reduced values of χ². The best result is obtained within the framework of the QBBC-opt_0 physical list, which is not optimized for medical applications. It is concluded that the accuracy of a patient’s radiation planning can be improved by developing alternative models of ionization of slow particles in biomaterials. A specific model is proposed, the development of which will help solve this problem.