空间质子辐射有效剂量测量的闪烁探测器理论设计

Theoretical design of a scintillation detector for space protons radiation effective dose measurements

有效剂量可解决航天员在空间飞行中所受质子辐射的危害比较与评价问题,在空间辐射危害评价中具有重要应用。为实现空间质子辐射有效剂量监测,针对空间各向同性质子辐射,利用蒙特卡罗程序设计了一种闪烁探测器。通过对探测器结构的特殊设计,在20-400 Me V能量范围内,各向同性质子在该探测器内沉积的能量与国际辐射防护委员会(International Commission on Radiological Protection,ICRP)116号报告提供的质子有效剂量基本成正比。通过探测质子沉积能量来监测质子辐射有效剂量,克服了直接测量有效剂量所存在的困难。对AP8MIN模型地球俘获带质子能谱与随机抽样质子辐射能谱,经数值计算,探测器给出的有效剂量与ICRP116号报告给出的有效剂量的相对偏差均小于±8%。

Background： Space protons radiation exposure is one of the most considerable concern in terms of radiation risk to astronauts during their occupational activities in space, and effective dose is important for the estimation of the radiation hazard. However, there is no technical way to monitor effective dose for space protons radiation until now. Purpose： This study aims to monitor the effective dose of space protons radiation to astronauts. Methods： Contraposing isotropic protons radiation in space, a scintillation detector was designed using Monte Carlo simulation program. By means of special design of the detector structure, the energy isotropic protons in the range of 20-400 MeV deposited in the detector is mostly proportional to the effective dose provided by International Commission on Radiological Protection （ICRP） report No.116. The effective dose is monitored by measuring the deposited energy. Results： For the proton energy spectra of AP8MIN model and random sampling, the relative deviation between the results of the ICRP report No. 116 and the detector is less than ±8% by numerical calculation. Conclusion： Theoretically, this detector can monitor the effective dose of space protons radiation to astronauts.