Production rates of cosmogenic helium‐3, neon‐21, and neon‐22 in ordinary chondrites and the lunar surface
Production rates of cosmogenic helium‐3, neon‐21, and neon‐22 in ordinary chondrites and the lunar surface
复制标题
普通球粒陨石和月球表面宇宙成因氦 3、氖 21 和氖 22 的生产率
DOI：
10.1111/j.1945-5100.2001.tb01906.x
复制
发表时间：
2001
期刊：
影响因子：
--
通讯作者：
R. Reedy
中科院分区：
文献类型：
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作者：
J. Masarik;K. Nishiizumi;R. Reedy
摘要-生产的3 He，21 Ne，和22 Ne在各种大小的流星体和在月球表面进行了调查。LAHET代码系统是一个计算宇宙射线粒子通量的纯物理模型，用于模拟宇宙射线粒子与地外物质的相互作用。我们讨论了屏蔽参数22 Ne/21 Ne的深度和尺寸依赖性，该参数用于重建大气层前的尺寸，深度和暴露历史。22 Ne/21 Ne的比值随着深度或大气层前的尺寸增加而减小，但在非常大的物体中则随着深度增加。22 Ne/21 Ne比率随深度增加，这意味着在某些大型物体中，这一比率并不能很好地反映屏蔽情况。计算了~ 3 He/~（21）Ne与~（22）Ne/~（21）Ne的关系，并讨论了与伯尔尼线的差别。
Abstract— The production of 3He, 21Ne, and 22Ne in meteoroids of various sizes and in the lunar surface was investigated. The LAHET code system, a purely physical model for calculating cosmic‐ray particle fluxes, was used to simulate cosmic‐ray particle interactions with extraterrestrial matter. We discuss the depth and size dependence of the shielding parameter 22Ne/21Ne, which is used for reconstruction of pre‐atmospheric sizes, depth, and exposure histories. The 22Ne/21Ne ratio decreases with increasing depth or pre‐atmospheric size but then increases with depth in very large objects. This increase with depth in the 22Ne/21Ne ratio means that this ratio is a poor indicator of shielding in some large objects. The dependence of 3He/21Ne as function of 22Ne/21Ne was also calculated, and differences between the calculations and the Bern line are discussed.