没有离子合的电子磁连接在地球的流磁层中
T D Phan1, J P Eastwood2, M A Shay3
1Space Sciences Laboratory, University of California, Berkeley, CA, USA. phan@ssl.berkeley.edu.
Nature
|May 11, 2018
概括
科学家观察到地球磁层中的电子喷射, 在没有离子合的情况下,这种过程驱动小规模电流板中的流能量传输.
科学领域:
- 血物理
- 太空物理
- 天体物理学
背景情况:
- 磁再连接将磁能转化为粒子能量, 这对于空间和实验室等离子体至关重要.
- 标准模型描述了电子尺度扩散区域的重新连接,其次是离子喷射.
- 再连接在动力尺度上的流等离体能量消散中的作用是理论化的,但缺乏观测证据.
研究的目的:
- 在小规模的流等离体中研究磁再连接和等离子体喷射.
- 在地球的磁层中重新连接.
- 探索标准离子合喷射之外的替代重新连接模型.
主要方法:
- 在地观测地球乱磁层中的电子尺度电流板.
- 对磁场,电场和粒子能量化的分析.
- 观察与标准和替代重新连接模型的比较.
主要成果:
- 在电子尺度电流板中检测到分歧的双向超离子-阿尔弗尼克电子喷射.
- 观察到平行电场和增强的磁对粒子能量转换.
- 没有发现离子喷射或更广泛的离子级电流层,
结论:
- 这项研究提供了第一次在小规模乱等离子体中重新连接等离子体喷射的观察证据.
- 一种新的连接形式,由电子喷射驱动而没有离子合,被确定.
- 这种电子尺度的重新连接机制有助于空间等离子体中的流能量转移和消散.
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