Studying the abundance of heavy nuclei produced in carbon therapy using Geant4 toolkit

Carbon-12 ion beams in the energy range of 100-450 MeV/u have excellent conditions for radiation-resistant and deep-seated tumors. At energies above 400 MeV/u, radiation is significantly affected by nuclear fragmentation processes of increasing depth. In this project, using the Geant4 toolkit, three physical models of Binary Intranuclear Cascade (BIC), Lige Intranuclear Cascade (INCL), and Quantum Molecular Dynamics (QMD) for heavy particles are defined in this toolkit. By examining the QMD model available in the Geant4 toolkit, the effects of heavy particles because of fragmentation of the nucleus by calculating the abundance of nuclei produced with an atomic number in the range 5>Z>1 (H, He, Li, Be and B particles) at different depths of the water phantom before and after the Bragg peak and the angular distribution of these particles have been investigated by this model. The particle abundance graph shows that particle production decreases with an increasing atomic number. H and He particles are the most abundant and their range is much broader than the range of primary carbon ions. Also, according to the angular distribution diagram, H and He particles have shown a much wider distribution. This is because they have the highest dose of deposition in the area outside the treatment field. Also, with increasing atomic numbers, the angular distribution decreases.