Enhancing shielding efficiency against galactic cosmic radiation: Secondary neutron optimization

Abstract

The objective of this study is to simulate shielding effectiveness against galactic cosmic rays, focusing on secondary neutrons. The simulation uses a combination of aluminum and poly-ethylene materials. A Monte Carlo simulation was conducted, with the particle and heavy ion transport code system - PHITS. The shielding effectiveness of aluminum and polyethylene was compared. The flux spectra of secondary emissions from the rear surface of the slab shielding were computed. Results indicate that secondary neutrons are mainly generated when galactic cosmic ray protons interact with shielding material. The proposed layered configuration suggests that placing the polyethylene layer on the inner side of the shielding structure significantly improves the overall performance of aluminum. Polyethylene efficiently moderates and reduces secondary neutrons. This improvement in shielding contributes meaningfully to the protection of astronauts and onboard electronic equipment during long-duration deep space missions , where galactic radiation is more intense and prolonged.