高度结构的缓慢太阳风从赤道冠状孔中出现
S D Bale1,2,3,4, S T Badman5,6, J W Bonnell5
1Space Sciences Laboratory, University of California, Berkeley, CA, USA. bale@berkeley.edu.
Nature
|December 6, 2019
概括
科学家使用帕克太阳探测器研究太阳风. 他们发现证据表明低度的冠状孔是缓慢的太阳风的关键来源,
科学领域:
- 太空物理学和太空物理
- 太阳物理
- 血物理
背景情况:
- 太阳风是来自太阳的等离子体流,
- 太阳风缓慢的起源及其加热机制仍然不确定.
- 在地球上之前的观测是混合和进化的太阳风, 掩盖源详情.
研究的目的:
- 调查太阳较近的缓慢太阳风的来源和特征.
- 确定太阳风加热和加速的机制.
主要方法:
- 使用帕克太阳探测器在36到54太阳半径的观测.
- 分析了磁场数据,等离子体流和波因廷流.
- 检查了微不稳定的等离子波测量.
主要成果:
- 观测到来自一个小赤道冠状孔的缓慢阿尔夫尼克太阳风.
- 检测到间歇性的磁场反转与等离子喷射和增强的波因廷流.
- 与等离子加热相关的电子和离子速度空间微不稳定性.
结论:
- 低度的冠状孔是缓慢的太阳风的重要来源.
- 在太阳风加热过程中,冲动式的能量化机制和微小的不稳定性起着至关重要的作用.
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