冠状孔的日常边界波动:原因和后果
I Ugarte-Urra1, Y-M Wang1, K Muglach2,3
1Space Science Division, Naval Research Laboratory, Washington, DC 20375 USA.
概括
冠状孔的边界每天都会因超颗粒对流和磁再连接而变化,从而影响变量缓慢的太阳风. 这些动态变化会影响太阳风的速度和密度测量.
科学领域:
- 太阳物理 太阳物理
- 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:
- 冠状孔是太阳冠状的开放磁场线的区域.
- 它们的边界是动态的,可以迅速变化.
- 了解这些变化对于太阳风预测至关重要.
研究的目的:
- 为了调查冠状孔边界波动的原因.
- 为了确定这些波动对缓慢的太阳风的影响.
主要方法:
- 来自SDO和STEREO航天器的极紫外线 (EUV) 图像的分析.
- 边界变化与超颗粒对流和磁活动的相关性.
- 与光球磁场的无电流提取结果进行比较.
主要成果:
- 冠状孔边界每天都会在几个超级颗粒的尺度上发生变化,由对流和磁重新连接驱动.
- 由于交换机重新连接,边界位移可以超过超颗粒大小.
- 这些波动是缓慢的太阳风变化的主要驱动因素.
结论:
- 超颗粒对流和磁重新连接是冠状孔边界动态的关键驱动因素.
- 观察到的边界变化直接解释了缓慢的太阳风速度和密度的变化.
- 突发的冠状孔形成可以通过互换重新连接而发生,而不会出现流量.
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