磁层牙振荡是由电离层外流引起的
O J Brambles1, W Lotko, B Zhang
1Thayer School of Engineering, Dartmouth College, Hanover, NH, USA. ojbrambles@dartmouth.edu
概括
地球的磁层表现出牙振荡,由太阳风相互作用驱动. 离子体O ((+) 流出是关键,喷射等离子体并导致磁场变化.
科学领域:
- 空间物理 空间物理
- 地质物理学 地质物理学
- 等离子体物理学的物理学
背景情况:
- 地球的磁层表现出周期性的牙振荡.
- 这些振荡是行星规模的,每2-4小时发生一次.
- 太阳风-磁层-离子层 (SW-M-I) 相互作用为这些振荡提供动力.
研究的目的:
- 研究电离层O ((+) 流出在产生牙振荡中的作用.
- 了解这些事件期间驱动磁层动态的机制.
主要方法:
- 利用地球空间的全球模拟.
- 分析了电离层O ((+) 流出对内磁层的影响.
主要成果:
- 电离层O ((+) 流出被确定为牙振荡的发生器.
- 流出的离子增加了压力,分散了夜边的磁场.
- 超过外流值会导致等离子体喷射和磁场双极化.
结论:
- 离子体O(+) 流出对于牙振荡产生至关重要.
- SW-M-I相互作用强度控制出流流动和振荡周期.
- 磁层动力学在半稳定对流和动态喷射事件之间发生变化.
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