Low‐energy (<100 eV) ion pitch angle distributions in the magnetosphere by ISEE 1
Low‐energy (<100 eV) ion pitch angle distributions in the magnetosphere by ISEE 1
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ISEE 1 磁层中低能（<100 eV）离子螺距角分布
DOI：
10.1029/ja088ia09p06944
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发表时间：
1983
影响因子：
--
通讯作者：
C. Chappell
中科院分区：
文献类型：
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作者：
T. Nagai;J. E. Johnson;C. Chappell
对来自 ISEE 1 等离子体成分实验的低能（<100 eV）离子数据进行统计检查，以研究磁层所有局部时间（L = 3-10）的俯仰角分布。这里使用的数据集中的俯仰角分布可以分为七种类型；然而，主要有四种类型，即各向同性分布、双向场对齐分布、单向场对齐分布和低通量。由非常低能量（通常<10 eV）离子组成的各向同性分布是内部区域的一个持久特征。经常观察到它伴随着损失锥状结构。由暖离子 (⩾10 eV) 组成的双向场对齐分布是白天外侧的持续特征，并且在夜晚一侧的各向同性分布区域之外可见。值得注意的是，损失锥状结构也是午间区域此类分布的共同特征。在外侧的夜侧，由暖离子组成的单向场对齐分布是主要特征，但在某些情况下，仅观察到低通量（没有明显的通量）。根据这些结果和其他结果讨论了不同区域的离子“来源”。
Low-energy (<100 eV) ion data from the plasma composition experiment on ISEE 1 are examined statistically to study pitch angle distributions in all local times of the magnetosphere (L = 3–10). The pitch angle distributions in the data set used here can be classified into seven types; however, there are four major types, i.e., isotropic distribution, bi-directional field-aligned distribution, unidirectional field-aligned distribution, and low flux. The isotropic distribution that consists of very low energy (typically <10 eV) ions is a persistent feature in the inner region. It is frequently observed with an accompanying loss cone-like structure. The bi-directional field-aligned distribution consisting of warm ions (⩾10 eV) is a persistent feature on the outer dayside and it is seen just outside the isotropic distribution region of the nightside. It is noted that the loss cone-like structure is also a common feature of this type of distribution in the noon sector. On the outer nightside the unidirectional field-aligned distribution consisting of warm ions is the dominant signature, but in some cases only the low flux (no appreciable flux) is observed. The ‘sources’ of ions in various regions are discussed on the basis of these results and others.