空间辐射粒子致航天员辐射剂量的蒙特卡罗模拟计算

Monte Carlo simulations of radiation dose of astronauts caused by space radiation particles

空间辐射是航天员执行空间站飞行任务过程中面临的主要风险之一。空间辐射粒子组成复杂,能量范围广泛,研究空间辐射粒子能谱对航天员的辐射剂量能够更好地辅助研究空间辐射粒子效应,进一步完善航天员安全保护机制。采用山东高等技术研究院阿尔法磁谱仪(AMS)测量的空间辐射粒子能谱和ICRP成人男性体素模型,基于蒙特卡罗工具包Geant4构建“天和”核心舱等比例模型,完成了模拟计算空间辐射粒子能谱对核心舱内航天员的辐射剂量,并通过粒子能谱通量数据估算了航天员于近地轨道空间站长期飞行所受到的空间辐射剂量。结果表明,空间辐射163天后皮肤剂量吸收率达到2.22 mGy·d^(-1),空间辐射粒子谱中占比仅0.5%的高能重离子贡献了空间辐射剂量的14.6%。该研究对航天员长期飞行辐射剂量的模拟计算、航天员健康风险评估和高能重离子辐射生物效应具有一定指导和参考意义。

Space radiation is one of the main risks for astronauts during space station missions.Because of the complex composition of space radiation particles and the wide range of energy,the study of space radiation particle spectrum can better assist the effect study of space radiation particle on astronauts.Also,the astronaut safety protection mechanism will be further improved.The spatial radiation particle spectrum simulated by Shandong Institute of Advanced Technology and the voxel model of ICRP adult male were used,and an equal-scale model of the“Tianhe”core module was constructed based on the Monte Carto program Geant4.The space radiation dose to astronauts during long-term space station mission in Low Earth Orbit(LEO)was estimated based on the particle flux data.The results show that the skin dose rate reaches 2.22 mGy·d^(-1) after 163 days in the core module of the space station,and the high energy heavy ions,although only 0.5%in the space radiation particle spectrum,contribute 14.6%of the space radiation dose.This study has some reference significance for astronaut risk assessment and biological effects of high energy heavy ion radiation.