不同屏蔽材料对空间100 MeV质子防护效果分析

Analysis of Shielding Ability of Different Materials for 100 MeV Proton Incident

为了研究地球空间辐射环境中高能质子的屏蔽问题,使用基于蒙特卡罗方法的Geant4软件模拟了100 MeV质子入射相同面密度的Al、PE、水三种屏蔽材料,通过分析射线穿过屏蔽材料后在水模体中的深度剂量分布、屏蔽材料内的能量沉积、屏蔽材料产生的次级粒子能谱,对不同面密度下三种材料的质子屏蔽效果进行了对比分析。结果表明:Al、PE、水三种屏蔽材料中,使用PE屏蔽材料比Al屏蔽材料节省27.29%的重量即可实现对100 MeV质子的有效屏蔽,水屏蔽材料比Al材料节省22.46%的屏蔽材料重量;面密度为6.48 g/cm^2PE材料对100 MeV质子的屏蔽能力比同等面密度下Al材料增加59.23%;等效Al厚度为27 mm时,PE屏蔽比Al屏蔽能力增加达到最大值82.96%。

In order to study the shielding of high-energy protons in the geospace radiation environment,Geant4 software which is based on Monte Carlo method was used to simulate the 100 MeV protons incident in three kinds of shielding materials including Al,PE and water with the same areal density.The shielding abilities of different shielding materials were compared by analyzing the depth dose distribution in the water,the energy deposition in the shielding material,and the secondary particle spectrum produced by the shielding material.The results showed that among the three shielding materials,PE used 27.29%less weight than that of the Al,while water saved 22.46%weight than that of the Al.The shielding ability of PE with a surface density of 6.48 g/cm2 was 59.23%higher than that of Al with the same surface density.The shielding ability of PE increased to 82.96%as compared with Al when the equivalent Al thickness was 27 mm.