Biomedical Engineering, University of Florida, Gainesville, FL 32611, USA. NASA Johnson Space Center, Houston, TX 77058, USA.
Phys Med Biol. 2013 Oct 21;58(20):7183-207. doi: 10.1088/0031-9155/58/20/7183. Epub 2013 Sep 24.
NASA currently uses one-dimensional deterministic transport to generate values of the organ dose equivalent needed to calculate stochastic radiation risk following crew space exposures. In this study, organ absorbed doses and dose equivalents are calculated for 50th percentile male and female astronaut phantoms using both the NASA High Charge and Energy Transport Code to perform one-dimensional deterministic transport and the Particle and Heavy Ion Transport Code System to perform three-dimensional Monte Carlo transport. Two measures of radiation risk, effective dose and risk of exposure-induced death (REID) are calculated using the organ dose equivalents resulting from the two methods of radiation transport. For the space radiation environments and simplified shielding configurations considered, small differences (<8%) in the effective dose and REID are found. However, for the galactic cosmic ray (GCR) boundary condition, compensating errors are observed, indicating that comparisons between the integral measurements of complex radiation environments and code calculations can be misleading. Code-to-code benchmarks allow for the comparison of differential quantities, such as secondary particle differential fluence, to provide insight into differences observed in integral quantities for particular components of the GCR spectrum.
美国国家航空航天局（NASA）目前使用一维确定性传输来生成在机组人员暴露于空间辐射后计算随机辐射风险所需的器官剂量当量值。在这项研究中，使用 NASA 高电荷和能量传输代码进行一维确定性传输，并使用粒子和重离子传输代码系统进行三维蒙特卡罗传输，为 50%男性和女性宇航员模型计算器官吸收剂量和剂量当量。使用两种辐射传输方法得出的器官剂量当量计算两种辐射风险度量，有效剂量和暴露诱导死亡风险（REID）。对于所考虑的空间辐射环境和简化的屏蔽配置，发现有效剂量和 REID 的差异较小（<8%）。然而，对于银河宇宙射线（GCR）边界条件，观察到补偿误差，这表明复杂辐射环境的积分测量与代码计算之间的比较可能会产生误导。代码间基准允许比较微分量，例如次级粒子微分通量，以深入了解 GCR 光谱特定分量的积分量中观察到的差异。
