Dyer C S, Truscott P R, Evans H, Sims A J, Hammond N, Comber C
Space and Communications Department, Defence Research Agency, Farnborough, UK.
Adv Space Res. 1996;17(2):53-8. doi: 10.1016/0273-1177(95)00512-d.
Secondary radiations produced by the interactions of primary cosmic rays and trapped protons with spacecraft materials and detectors provides an important, and sometimes dominant, radiation environment for sensitive scientific instruments and biological systems. In this paper the success of a number of calculations in predicting a variety of effects will be examined. The calculation techniques include Monte Carlo transport codes and semi-empirical fragmentation calculations. Observations are based on flights of the Cosmic Radiation Environment and Activation Monitor at a number of inclinations and altitudes on Space Shuttle. The Shuttle experiments included an active cosmic-ray detector as well as metal activation foils and passive detector crystals of sodium iodide which were counted for induced radioactivity soon after return to earth. Results show that cosmic-ray secondaries increase the fluxes of particles of linear energy transfer less than 200 MeV/(gm cm-2), while the activation of the crystals is enhanced by about a factor of three due to secondary neutrons. Detailed spectra of induced radioactivity resulting from spallation products have been obtained. More than a hundred significant radioactive nuclides are included in the calculation and overall close agreement with the observations is obtained.
初级宇宙射线和捕获质子与航天器材料及探测器相互作用产生的次级辐射，为灵敏的科学仪器和生物系统提供了一个重要且有时占主导地位的辐射环境。本文将考察一些计算在预测各种效应方面的成功情况。计算技术包括蒙特卡罗输运代码和半经验碎片计算。观测基于搭载宇宙辐射环境与活化监测器的航天飞机在多个倾角和高度的飞行。航天飞机实验包括一个有源宇宙射线探测器以及金属活化箔和碘化钠被动探测器晶体，在返回地球后不久对其进行诱导放射性计数。结果表明，宇宙射线次级粒子增加了线能量转移小于200 MeV/(gm cm-2)的粒子通量，而晶体的活化因次级中子而增强了约三倍。已获得散裂产物产生的诱导放射性的详细能谱。计算中包含了一百多种重要的放射性核素，总体上与观测结果吻合良好。
