在日膜过渡区域中没有 меридионального等离子体流
Robert B Decker1, Stamatios M Krimigis, Edmond C Roelof
1Applied Physics Laboratory, The Johns Hopkins University, Laurel, Maryland 20723, USA. robert.decker@jhuapl.edu
Nature
|September 8, 2012
概括
旅行者1号探测到接近零的辐射等离子流在日光,与模拟相矛盾. 衡量午线流的测量也显示了与零一致的速度,表明超出太阳风影响之外的意想不到的等离子体行为.
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.
背景情况:
- 旅行者1号进入了日层,这是太阳风终结冲击之外的加热等离子体区域.
- 模拟预测,日表层等离子体将沿日间流向午线流动,将太阳和星际等离子体分开.
研究的目的:
- 用旅行者1号的数据调查日光的等离子体流动力学.
- 为了测试血偏移在日间暂停时的理论预测.
主要方法:
- 分析了旅行者1号在两年时间内的等离子体流速数据.
- 利用航天器的重新定位,使低能量带电粒子仪器能够测量午线流.
主要成果:
- 观察到到2010年4月,辐射等离子体流的速度逐渐减慢至接近零的速度.
- 测量了+3±11公里/秒的午线流速,统计学上与零一致.
结论:
- 旅行者1号的数据挑战了现有的太阳层等离子体流动模型.
- 观察到的接近零的午线流量表明,在日间断处的相互作用与之前预期的不同.
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