面向空间高能重离子与辐射屏蔽材料的反应截面地基研究
Groundbased Research on Cross Sections of Radiation Shielding Material with High Energy Heavyion
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摘要: 空间辐射尤其是高能重离子辐射可造成生物机体的严重损伤， 所以对高能重离子进行恰当的辐射屏蔽， 成为实现载人航天的关键性因素之一。 研究表明， 由于高能重离子与不同屏蔽材料发生相互作用， 所产生的核碎片等次级粒子， 直接影响空间辐射屏蔽材料的屏蔽性能研究和屏蔽结构设计。 介绍了太空辐射的分类与组成， 综述了国际地基辐射屏蔽材料与实验现状。 根据文献中的地基实验数据， 重点描述了被动式屏蔽方法： 以相近能量多种重离子， 不同能量的56Fe和28Si重离子分别与C， H， Al和Cu材料相互作用的总反应截面和碎片产生截面， 并结合510 MeV/u 56Fe与不同厚度CH2相互作用产生的碎片通量分布、 碎片平均LET分布和不同厚度CH2的单位入射离子剂量减少量等方面， 系统讨论分析了C， H， Al， Cu和CH2等常用空间辐射屏蔽材料的屏蔽性能。 Cosmic radiation， particularly the highenergy heavyion radiation， may cause serious injury on living organism. Therefore， it is one of critical restriction factor in Manned Spaceflight. Studies show that highenergy heavy ions interacting with the shielding materials can produce numerous kinds of fragments and secondaries. These particles have a direct impact on evaluation of shielding properties of different shielding materials， the optimal shielding structure design and lowdose evaluation after shielding materials. From perspectives of divisions of cosmic rays and passive shielding methods， this paper introduces the groundbased research of shielding materials. The passive shielding method was discussed, based on the experimental data of the total cross sections and fragment（production） cross sections of the aspects of different heavy ions with approximately same energy and 56Fe， 28Si heavy ions with different energies on H， C， CH2， Al and Cu radiation shielding materials. In addition， the fragment fluency distribution， the average LET distribution and the dose reduction per particle of 510 MeV/u 56Fe in different depth of CH2 material were also discussed.Abstract: Cosmic radiation， particularly the highenergy heavyion radiation， may cause serious injury on living organism. Therefore， it is one of critical restriction factor in Manned Spaceflight. Studies show that highenergy heavy ions interacting with the shielding materials can produce numerous kinds of fragments and secondaries. These particles have a direct impact on evaluation of shielding properties of different shielding materials， the optimal shielding structure design and lowdose evaluation after shielding materials. From perspectives of divisions of cosmic rays and passive shielding methods， this paper introduces the groundbased research of shielding materials. The passive shielding method was discussed, based on the experimental data of the total cross sections and fragment（production） cross sections of the aspects of different heavy ions with approximately same energy and 56Fe， 28Si heavy ions with different energies on H， C， CH2， Al and Cu radiation shielding materials. In addition， the fragment fluency distribution， the average LET distribution and the dose reduction per particle of 510 MeV/u 56Fe in different depth of CH2 material were also discussed.
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