Evaluation of the photon emission in an accelerator-driven 14-MeV fusion neutron source

Abstract This study presents a comprehensive analytical evaluation of the photon background components arising in a 14-MeV accelerator-driven fusion neutron source. The analysis accounts for photons generated by accelerated ions interacting with a representative target, as well as those originating directly from fusion reactions and from secondary fusion products. In particular, a mixed deuterium/tritium ion beam at 300 keV is considered under two representative scenarios: 1) a pure monatomic deuterium/tritium beam in a 50/50 ratio and 2) a deuterium/tritium beam (50/50) comprising varying proportions of monatomic, diatomic and triatomic species of both isotopes. To ensure realistic modeling, the analytical calculations, based on the theoretical framework of the particle-induced X-ray emission, incorporate the physical parameters of the ion source currently being developed for the SORGENTINA-RF facility. The analytical findings are further validated through Monte Carlo simulations performed with the GEANT4 toolkit. The results of this work are essential for the precise characterization of the radiation environment during neutron flux measurements and for the effective management of radiation protection in fusion neutron facilities.