GEANT4 & GAMOS — A particle implementation of high energy simulation toolkit to oncology therapy

Monte-Carlo simulation is an essential tool that assists in the design of new medical imaging devices; optimize the treatment planning in dose estimation to control tumors in oncology therapy. Geant4 and GAMOS (Geant4 based Application for Medicine Oriented Simulations) implements the optimized radiotherapy external beam application, the propagation through an accelerator geometry and the calculation of the dose in voxel phantoms. This paper gives an overview of the physical processes involved along with detailed description of the design and implementation to medical physics in Geant4 and GAMOS toolkits. We have calculated the dose deposition of a passive proton beam of 60 to 240 MeV in a human phantom geometry. The resulting Bragg peak, range, penumbra width has been calculated and verified with results of other groups. The applications of these systems in fields of nuclear fragmentation for carbon ion therapy, nuclear imaging and hadrontherapy for in vivo dose monitoring are also discussed.