全球范围的连贯调制辐射带电子损失的辐射带电子损失来自于等离子体球 hiss
A W Breneman1, A Halford2, R Millan2
1School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA.
Nature
|July 1, 2015
概括
地球辐射带中的电子损失是由等离子体圈的声引起的. 这项研究直接观察了这些损失,揭示了与等离子体密度和磁场波动相关的快速大变化.
科学领域:
- 空间物理 空间物理
- 等离子体物理学的物理学
- 地质物理学 地质物理学
背景情况:
- 地球辐射带中的电子损失,特别是在等离子圈内,长期以来一直被认为是与等离子圈的相互作用造成的.
- 这一过程对于在地磁风暴后恢复辐射带结构至关重要.
- 之前的观测证实了长期电子损失率,但缺乏对时间和空间动态的直接验证.
研究的目的:
- 直接验证由等离子球升起引起的辐射带中电子损失的时间和空间动态.
- 调查电子损失事件与等离子球的特征之间的关系.
- 了解等离子体密度和磁场调制对这些损失动态的影响.
主要方法:
- 同时测量辐射带电子损失和等离子体升高.
- 观测bremsstrahlung X射线由 hiss-scattered电子产生影响大气中的X射线.
- 分析与等离子体密度和磁场变化相关的电子损失动态.
主要成果:
- 直接观察结构化的辐射带电子损失与等离子体升高相关.
- 电子损失动态在短时间尺度 (1-20分钟) 上显示出显著的变化 (高达数量级).
- 观察到电子损失和 hiss 动态之间的近全球范围的连贯性,这是意想不到的.
结论:
- 这项研究提供了直接的证据,将等离子体声与辐射带中的快速,结构化的电子损失联系起来.
- 等离子体密度和磁场的快速调制显著影响了电子损失动态.
- 在损失动态中发现的全球范围的连贯性可能会影响活动期间的短期辐射带演变.
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