Radiation dose analysis in the IR-IECF device: numerical analysis with geant4 simulation and experimental measurements

Abstract

This study presents a combined experimental and Geant4-based assessment of the radiation field and shielding performance of the Iranian Inertial Electrostatic Confinement fusion device (IR-IECF) operating in deuterium–deuterium (D–D) mode and producing 2.45 MeV neutrons. A detailed Geant4 model of the IR-IECF device, its surrounding borated-polyethylene shielding, and the relevant dosimetry locations was developed to calculate neutron and gamma dose distributions. Experimental gamma doses were measured using GR-200 (LiF:Mg,Cu,P) thermoluminescent dosimeters, whereas neutron ambient dose-equivalent rates were measured using a Berthold LB6411 rem counter. In the Geant4 model, neutron dose scoring was performed using LiF-based virtual dosimeters positioned at the corresponding monitoring locations, allowing the numerical results to be compared with the experimental neutron measurements. The simulated neutron and gamma dose values showed good agreement with the corresponding experimental data, supporting the reliability of the developed Geant4 model for radiation-field characterization. In addition, a dedicated secondary-particle scoring analysis was performed to characterize the secondary radiation generated during neutron transport. Electrons, protons, and photons were the dominant recorded secondary particles, while secondary neutrons accounted for approximately 1.69% of the recorded secondary tracks. Overall, the combined experimental and numerical approach provides a practical framework for radiation-field characterization and shielding assessment of IECF-based neutron sources.