Evaluation of shielding materials against galactic cosmic rays for protecting astronauts

Exposure to Galactic Cosmic Rays (GCR) presents significant health risks to astronauts during long-duration deep space missions. Although existing studies have examined dose and particle energy spectra under GCR exposure scenarios, there is still a lack of studies covering various shielding quantities, especially regarding the self-shielding transmission characteristics of the human body. In this study, we used Monte Carlo simulations with the PHITS codes, coupled with the ICRP male reference phantom, to evaluate the performance of shielding materials against GCR. We comprehensively analyzed several physical quantities, including organ dose equivalent, absorbed dose, effective dose equivalent, and the flux and dose of secondary particles. Our findings analyzed the body's self-shielding effect and proton dose buildup effect. This study provides systematic data that offers valuable insights into astronaut safety during deep space exploration.