Enhancements of lobe ion density and velocity associated with plasmoids
Enhancements of lobe ion density and velocity associated with plasmoids
复制标题
与等离子体团相关的叶离子密度和速度的增强
DOI：
10.1029/2001ja900086
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发表时间：
2001
影响因子：
--
通讯作者：
T. Mukai
中科院分区：
文献类型：
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作者：
H. Shirai;T. Takada;Y. Kamide;T. Mukai
GEOTAIL 航天器在遥远的磁尾 (∼100–200 RE) 中观察到叶离子密度和速度的间歇性增强。它们是在等离子体团通过后观察到的，伴随着 Bz 从南到北的双极变化，其极性与等离子体团或移动压缩区域观察到的极性相反。当 Bz 从南向北变化时（即当 Bz = 0 时），离子密度出现峰值。为了解释这些观察结果，提出了一个模型，其中磁尾在等离子体团后面收缩。有人认为，等离子体团形成后，近地中性线跟随等离子体团向后延伸。同一航天器观察到的等离子体团通过和离子增强之间的延迟约为 5-70 分钟，具体原因尚不清楚。
Intermittent enhancements of lobe ions in density and velocity were observed by the GEOTAIL spacecraft in the distant magnetotail (∼100–200 RE). They were observed after the passage of plasmoids, accompanying south-to-north bipolar variations in Bz, which are opposite in polarity to those observed with plasmoids or traveling compression regions. The peaks in the ion density occurred when Bz changed from south to north (i.e., when Bz = 0). To explain these observations, a model is presented in which the magnetotail shrinks behind a plasmoid. It is suggested that after the formation of a plasmoid the near-Earth neutral line runs tailward following the plasmoid. The delay between the plasmoid passage and the ion enhancement observed by the same spacecraft is ∼5–70 min, depending on as yet unknown reasons.