New Geant4 electromagnetic physics developments for ion therapy applications

We have developed simulation codes to handle electromagnetic process in Geant4 in an attempt to improve the accuracy of dose calculations for ion radiotherapy. Geant4 is a Monte Carlo simulation toolkit for simulating the passage of particles through matter, and capable of handling all physics processes including electromagnetic, hadronic and nucleus-nucleus interactions which are indispensable to calculate three-dimensional dose distributions in ion therapy. In this work we report the recent progress for Geant4 models for ions and new validation results, which were obtained for depth-dose distributions of carbon ions incident on water against experimental measurements. We found simulations to reproduce the experimental data fairly well. (author)