The Evolution of the Plasma Sheet Ion Composition: Storms and Recoveries
The Evolution of the Plasma Sheet Ion Composition: Storms and Recoveries
复制标题
等离子体片离子成分的演变：风暴与恢复
DOI：
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发表时间：
2017
期刊：
影响因子：
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通讯作者：
H. Spence
中科院分区：
文献类型：
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作者：
M. Denton;M. Thomsen;G. Reeves;B. Larsen;M. Henderson;V. Jordanova;P. Fernandes;R. Friedel;R. Skoug;H. Funsten;E. MacDonald;H. Spence
离子等离子体片（~几百eV至~几十keV）通常由H+离子主导。在这里，在单个事件期间以及在54个平静到风暴事件和21个活跃到平静事件期间，对等离子体片内的离子组成的变化进行了探索。来自货车艾伦探测卫星上HOPE（氦、氧、质子、电子）仪器的离子组成数据提供了等离子体片中H+、O+和He+离子通量的特殊空间分辨率和时间分辨率。H+被证明是在平静到风暴过渡的等离子体片中的主导离子。然而，在延长的平静间隔期间，每个离子的能通量以准线性方式变化。重离子（O+和He+）在电荷交换反应导致H+比O+或He+损失更快的时期变得越来越重要。结果证实了先前的研究，表明等离子体片的离子组成可以在很大程度上理解（和预测）在平静间隔期间，从知识（a）在平静条件开始时先前注入的等离子体的组成和（B）使用简单的漂移物理模型结合电荷交换损失的计算。
The ion plasma sheet (~few hundred eV to ~few tens keV) is usually dominated by H+ ions. Here changes in ion composition within the plasma sheet are explored both during individual events and statistically during 54 calm‐to‐storm events and during 21 active‐to‐calm events. Ion composition data from the HOPE (Helium, Oxygen, Proton, Electron) instruments onboard Van Allen Probes satellites provide exceptional spatial resolution and temporal resolution of the H+, O+, and He+ ion fluxes in the plasma sheet. H+ is shown to be the dominant ion in the plasma sheet in the calm‐to‐storm transition. However, the energy‐flux of each ion changes in a quasi‐linear manner during extended calm intervals. Heavy ions (O+ and He+) become increasingly important during such periods as charge‐exchange reactions result in faster loss for H+ than for O+ or He+. Results confirm previous investigations showing that the ion composition of the plasma sheet can be largely understood (and predicted) during calm intervals from knowledge of (a) the composition of previously injected plasma at the onset of calm conditions and (b) use of simple drift‐physics models combined with calculations of charge‐exchange losses.
影响因子：
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作者：
M. Denton;J. Borovsky
通讯作者：
M. Denton;J. Borovsky