Modelling therapeutical 3He beams

At present various sites around the world use beams of swift protons or carbon ions for radiotherapy. The success of the GSI C radiotherapy pilot project has triggered the planning and/or construction of numerous clinical ion facilities in Germany (Heidelberg, Marburg, Berlin) and Europe (CNAO, MedAustron, Etoile). These sites will use carbon ions and also protons as their prime modalities. There are, however, physical and radiobiological reasons to inspect other light ion species for their potential therapeutical advantages. In particular helium ions undergo less lateral scattering than protons and less nuclear fragmentation than carbon. Consequently, the HIT facility was designed to also offer helium beams as an option, which means that eventually physical and radiobiological models must be as patient-ready as they are now for C.