Inertial electrostatic confinement fusion (IECF) devices generate a mixed radiation field consisting of 2.45 MeV D–D neutrons and secondary gamma rays, which requires carefully optimized shielding for safe laboratory operation. In this study, the IR-IECF device was modeled using Geant4 based on its as-built geometry, and neutron–gamma dose rates were evaluated at predefined locations assuming an isotropic D–D neutron source. A source-to-inner-shield distance of 150 cm was selected to represent the actual laboratory installation. Candidate shielding materials—including polyethylene, borated polyethylene, lead, tungsten, standard concrete, and borated concrete—were evaluated using transmitted dose reduction and tenth-value layer (TVL) metrics. The results indicate that borated polyethylene provides the most effective attenuation of fast neutrons, while high-Z materials such as lead show superior performance in reducing the gamma component. Based on these results, a multilayer shielding configuration is recommended, consisting of an inner hydrogenous/borated layer for neutron moderation and capture, combined with an outer gamma-attenuating layer. The proposed approach provides a practical Geant4-based framework for shielding material selection and thickness optimization for IR-IECF systems in laboratory-scale deployments. • Neutron–gamma shielding performance of an IR IECF neutron source was systematically evaluated using Geant4 Monte Carlo simulations. • Dose attenuation was quantified for a 2.45 MeV D–D neutron spectrum at a fixed 150 cm source–detector distance. • TVL-based metrics were employed to rank candidate shielding materials under identical geometrical conditions. • 10% borated polyethylene exhibits the minimum neutron TVL, indicating superior fast neutron attenuation efficiency. • Optimized multilayer shields combining borated polyethylene and lead achieve the lowest combined neutron–gamma dose.
Pour et al. (Fri,) studied this question.