Effectiveness of Multi-Layered Radiation Shields Constructed from Polyethylene and Metal Hydrides Using HZETRN and OLTARIS for Space Applications

VV, Sreedevi; Lalwani, Kavita

doi:10.22034/jsst.2025.1520

Effectiveness of Multi-Layered Radiation Shields Constructed from Polyethylene and Metal Hydrides Using HZETRN and OLTARIS for Space Applications

Document Type : Original Research Paper

Authors

Sreedevi VV

Kavita Lalwani

Department of Physics, Malaviya National Institute of Technology Jaipur, India

10.22034/jsst.2025.1520

Abstract

A major challenge for extended human spaceflights in deep space is the dangerous exposure to space radiation. These high-energy particles pose significant risks to astronaut health. To mitigate these risks, effective radiation shielding is essential. In previous studies, aluminium has been used as a multilayer shielding material in GCR (Galactic Cosmic Rays) space radiation environment with high dose equivalent. Because of aluminium's secondary particle production, the overall effective dose equivalent for astronauts behind an aluminium shield is higher than for more advanced shielding materials. To further reduce the dose equivalent, the shielding effectiveness of various metal hydrides in GCR free space environment is investigated using HZETRN2015 (High charge (Z) & Energy TRaNsport) and OLTARIS (On-Line Tool for the Assessment of Radiation In Space) in this work. Metal hydride materials are chosen because of their capacity to store hydrogen. Among these materials, lithium hydride has demonstrated superior effectiveness as a radiation shield. Given this, the potential of a multilayer shield composed of polyethylene and lithium hydride is also being explored considering the tensile strength certain varieties of polyethylene like UHMWPE (Ultra High Molecular Weight Poly-Ethylene) can provide. In multilayer shielding, different materials can target different types of radiation, providing more comprehensive protection. The results from HZETRN2015 and OLTARIS transport codes are compared and found in agreement.

Keywords

Space Radiation

Metal Hydrides

Polyethylene

HZETRN

OLTARIS

Subjects

Measuring the effectiveness of radiation on space systems

Article Title Persian

Effectiveness of Multi-Layered Radiation Shields Constructed from Polyethylene and Metal Hydrides Using HZETRN and OLTARIS for Space Applications

Authors Persian

سری‌دِوی وی. وی

کاویتا لالوانی

گروه فیزیک، دانشکاه ملی فناوری مالاویا جیپور،هند

Abstract Persian

A major challenge for extended human spaceflight in deep space is the hazardous exposure to space radiation, which consists of high-energy particles that pose significant risks to astronaut health. Effective radiation shielding is essential to mitigate these risks. This study optimizes the shielding performance of a multi-layered structure composed of polyethylene and metal hydrides for space applications. Using two simulation tools: HZETRN and OLTARIS, developed by NASA, we model these structures and evaluate dose equivalent in a Galactic Cosmic Ray (GCR) free-space radiation environment, which is the primary and major contributor to radiation exposure for long-duration space missions. Among the materials studied, lithium hydride exhibits the highest shielding effectiveness. The results on the dose equivalent are compared with aluminum, a conventional shielding material, revealing that the multi-layered structure constructed from polyethylene and lithium hydride provides a 54.9% improvement in shielding effectiveness while maintaining structural stability. Additionally, the dose equivalent contribution of different radiation particles (protons, alpha particles, and heavy ions) and their flux are analyzed for further validation across both tools. Our results highlight the effectiveness of multi-layered shielding in reducing dose equivalent while maintaining structural stability, making it a viable solution for deep-space missions.

Keywords Persian

Space radiation

Metal hydrides

Polyethylene

HZETRN

OLTARIS

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