Comparison of dose localization properties of carbon and proton beams

New charged particle accelerators for radiotherapy applications are currently being discussed and designed. Thus, the question of which particle beams are optimal for specific clinical applications needs to be investigated. Dose localization plays an important role in treatment. Theoretical considerations based on multiple scattering theories indicate that carbon beams have better dose localization properties than proton beams because heavier charged particles scatter less than lighter ones. We have measured dose distributions produced by narrowly collimated carbon and proton beams using an identical experimental setup thus allowing a direct comparison. 3 figs