Radiation Shielding and Activation Analyses for Neutron Activation Measurement Facility at Advanced Radiation Technology Institute, Jeongup

Background: Experiments to measure the neutron activation cross-section using the 30 MeV cyclotron at Advanced Radiation Technology Institute are planned. Neutrons, generated during experiments, will activate the devices and affect the surrounding area of the facility. Therefore, analyses were conducted to confirm the radiation shielding of the facility and investigate the effects of neutron radiation.Materials and Methods: Two devices were installed for neutron activation cross-section measurements: a beam energy measurement device and a neutron generator. Monte Carlo simulation was used to investigate the effect of neutrons produced by the neutron generator on the facility and its surroundings.Results and Discussion: Dose rate distribution inside and around the facility during beam irradiation (BI) was investigated for the radiation shielding analysis. Furthermore, the dose rates at key locations around the facility were calculated and compared to the public or occupational dose limits. The activation analysis involves calculating major nuclide activities. Additionally, the dose rates that workers would receive after 30-minute and 1-hour BI were computed.Conclusion: The dose rate in the surrounding area of the facility is <0.5 μSv·hr−1, which is lower than the public dose limit. Accessing the facility takes 5 hours after the beam off for 1-hour BI and 3 hours after the beam off for 30-minute BI.