太阳风终止冲击的介导由非热离子介导
R B Decker1, S M Krimigis, E C Roelof
1The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland 20723, USA. robert.decker@jhuapl.edu
Nature
|July 4, 2008
概括
太阳罩中的高能离子显著影响太阳风的终结冲击. 旅行者2号探测到的这些非热离子控制着冲击结构和能量转移.
科学领域:
- 空间物理 空间物理
- 太空物理学 太空物理学
- 等离子体物理学的物理学
背景情况:
- 太阳风终结冲击是太阳风等离子体减速的区域.
- 旅行者1号和2号航天器之前已经测量了太阳风和太阳层中的粒子.
- 这些粒子在冲击过渡物理学中的作用仍然不清楚.
研究的目的:
- 为了研究非热粒子对终结冲击和层动态的影响.
- 为了分析来自旅行者2号冲击穿越的等离子体和磁场数据.
主要方法:
- 利用了来自旅行者2号航天器的等离子体和磁场仪器数据.
- 分析的粒子强度测量,特别是低能离子 (>0.028 MeV).
- 将非热离子压力与热等离子体和磁场压力进行比较.
主要成果:
- 旅行者2号在终结冲击的两侧检测到高强度的非热离子和电子.
- 发现层中的非热离子压力与热等离子体和磁场压力相当或超过.
- 这些低能离子在终结冲击结构中起着至关重要的作用.
结论:
- 非热离子分布是终结冲击和层中的动态过程的关键.
- 这些离子的加速提取了太阳风的大量流动动能量的很大一部分.
- 这些发现澄清了能量粒子对终结冲击物理学的影响.
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