Multi-layered shielding materials for high energy space radiation

One of the biggest challenges of the human spaceship in deep space is the harmful space radiation environment. In this paper, we present a multi-layered shielding approach, which reduces the radiation exposures from the trapped radiation, Solar Particle Events (SPE), and Galactic Cosmic Radiation (GCR). We have used shielding materials namely aluminum (Al), Polyethylene (PE), Hydrogen stored boron nitride, Water, Polybenzoxazine, Epoxy, Kevlar, Zylon, Polyetherimide, Polysulfone, Lithium Hydride (LiH), Liquid Methane, and Hydrogenated Graphite Nanofiber (HGNF) respectively. The dose equivalent (DE) for each shielding material is calculated using an On-line Tool for the Assessment of Radiation In Space (OLTARIS) and High Charge and Energy TRaNsport (HZETRN) for 2010 Solar minimum GCR. In addition, the dose equivalent for the first Al slab of 10 g/cm2 followed by a different combination of materials slabs of 90 g/cm2 is analyzed. In multi-layered analysis, we observed that Al + LiH is more effective than remaining shielding materials. In addition, combinations of hydrogen, boron, and nitrogen-rich materials slabs behind the Al slab are studied. In this analysis, the dose equivalent reduction per unit thickness is higher in the first hydrogen-rich material slab of a shield than over any of the other materials slabs. In Sandwich combinations, PE, LiH, Liquid Methane, and Hydrogen stored boron nitride sandwiched between Al. Al + LiH + Al showed better performance. In addition, the dose equivalent was compared between OLTARIS and HZETRN transport codes.