空间重离子在水模体中剂量深度分布的蒙特卡罗模拟

Monte-Carlo Simulation of Space Heavy Ion Dose Depth Distribution in Water Phantom

利用蒙特卡罗方法模拟计算了56 GeV铁离子穿过简化空间飞行器中水模体的总剂量深度分布以及次级粒子剂量深度分布,统计了次级中子在水模体中的通量深度分布。计算结果表明:56 GeV铁离子穿过简化空间飞行器在水模体中产生较完整的布拉格曲线,并且次级核碎片对总剂量的贡献达到了58%,其次是初始入射的铁离子以及电子和质子,其他的粒子对总剂量贡献比例较小,可忽略不计。次级中子通量在布拉格峰值附近达到最大值。

Total and the different secondary particles dose depth distribution were estimated in the water phantom by Monte-Carlo simulation of the particle transportation when 56 GeV iron ion passed the simplified spacecraft. The secondary neutron flux depth distribution was also estimated in the water phantom. The results showed that: a Bragg curve was achieved for the total dose depth distribution in the water phantom; the secondary nuclear fragments had the largest contribution to the total dose,which was 58%,followed by the initial incident iron ion,electron and proton; other particles contributed a smaller proportion of the total dose which was negligible; the secondary neutron flux reached its maximum near the Bragg peak.