质子剂量微分谱预估空间辐射剂量

利用M on te C arlo方法结合小体积元人体模型对航天员空间质子辐射剂量进行估算。使用核磁共振全身扫描图像,通过识别组织器官,再利用参考人数据,建立由4mm×4mm×4mm小体积元组成的人体模型。该人体模型包括23种辐射敏感器官,并用查找表技术压缩模型数据。使用GEANT 4 M on te C arlo程序包,结合该模型,计算得到各个组织器官单能质子入射下的微分剂量估计谱库。对空间质子微分注量谱和微分剂量能谱积分,得到空间辐射剂量估计值。估算出1972年8月太阳质子事件的皮肤当量剂量为9 256 cSv,与文献值9 350 cSv相近,验证了算法的可行性。

Dose assessment for space radiation using a proton differential dose spectrum

A Monte Carlo method using a voxel-based human model was used to evaluate radiation doses for astronauts.The model used cubic voxels 4 mm on each side using magnetic resonance imaging.The model was segmented into 23 radiosensitive anatomic regions and compressed using a look-up table.The doses in each organ and tissue due to incident monoenergy protons were calculated using the GEANT4 Monte Carlo code combined with this model.The human dose assessment for space radiation was obtained from the proton differential spectrum and the integral of the differential dose energy spectrum.The results for the skin equivalent dose for the Aug.1972 solar particle event is 9 256 cSv which agrees well with the accepted value of 9 350 cSv in other references.