GEANT4 Target Simulations for Low Energy Medical Applications

The GEANT4 code offers an extensive set of hadronic models for various projectiles and energy ranges. These models include theoretical, parameterized and, for low energy neutrons, data driven models. Theoretical or semi-empirical models sometimes cannot reproduce experimental data at low energies(<100MeV), especially for low Z elements, and therefore recent GEANT4 developments included a new particle\hp package which uses evaluated nuclear databases for proton interactions below 200 MeV. These recent developments have been used to study target designs for low energy proton accelerators, as replacements of research reactors, for medical applications. Presented in this paper are results of benchmarking of these new models for a range of targets, from lithium neutron production targets to molybdenum isotope production targets, with experimental data. Also included is a discussion of the most promising target designs that have currently been studied.