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一个磁性重新连接X线延伸超过390地球半径在太阳风的太阳风
T D Phan1, J T Gosling, M S Davis
1Space Sciences Laboratory, University of California, Berkeley, California 94720, USA. phan@ssl.berkeley.edu
Nature
|January 13, 2006
概括
磁再连接对于能量转换至关重要,它被证明是一个大规模的过程,并不是固有的不齐. 这一发现挑战了以前关于太空环境中的磁重新连接的假设.
科学领域:
- 血物理学的等离子体物理学
- 太空物理空间物理学
- 天体物理学 天体物理学
背景情况:
- 磁再连接将磁能转化为粒子能量,在各种自然和实验室环境中至关重要.
- 磁力重新连接的规模 (不完整或扩展) 仍然是一个关键的未解答问题.
- 在地球磁层的观测表明局部的,不一致的重新连接.
研究的目的:
- 为了研究磁再连接的基本尺度.
- 为了确定重新连接是否本质上是不稳定的,还是大规模的现象.
- 了解磁再连接发生的条件.
主要方法:
- 利用三艘航天器的观测数据来分析磁再连接期间的加速流.
- 检查了嵌入太阳风流中的电流板中的重新连接事件.
- 分析了28个不同的重新连接事件以确定统计学意义.
主要成果:
- 观察到一个重新连接的X线延伸至少390地球半径 (2.5 x 10^6公里).
- 有证据表明,磁再连接基本上是一个大规模的过程.
- 再连接可以在近乎稳定的状态下发生,即使没有外部驱动流.
结论:
- 磁再连接主要是一个大规模的过程,与一些磁层观测相反.
- 地球磁层的不稳定重新连接很可能是由于边界条件,而不是内在特性.
- 再连接可以几乎稳定地运行,独立于外部流动力学.
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