Magnetosphere response to high-speed solar wind streams: A comparison of weak and strong driving and the importance of extended periods of fast solar wind
Magnetosphere response to high-speed solar wind streams: A comparison of weak and strong driving and the importance of extended periods of fast solar wind
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DOI：
10.1029/2011ja017124
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发表时间：
2012-09
影响因子：
--
通讯作者：
M. Denton;J. Borovsky
中科院分区：
文献类型：
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作者：
M. Denton;J. Borovsky
在最近延长的太阳活动极小期(2006-2010年)期间，磁层对太阳风的反应受到了极大的关注。尽管按某些参数(如太阳黑子的数量)分类时，这一时期格外平静，但太阳风仍然包含影响地球磁层并造成地磁扰动的特征。重复的共转相互作用区(CIR)和相关的高速太阳风流(HSS)通常与太阳周期的衰退期有关，是最近太阳活动极小期太阳风的常规特征。在这里，我们比较和对比太阳风中的强HSS和弱HSS以及它们在地球磁层中的后续影响。我们发现等离子体层、离子和电子等离子体片以及外电子辐射带中的强HSS效应和弱HSS效应之间存在显著差异。外辐射带的密度-温度描述揭示了为什么在强HSS到达后辐射带通量返回到比强HSS之前更高的水平，以及为什么在弱HSS到达后辐射带通量返回到比弱HSS之前更低的水平。
Much attention has been focused on the reaction of the magnetosphere to the solar wind during the recent extended solar minimum (2006–2010). Although this period was exceptionally quiet when categorized by some parameters (e.g., the number of sunspots) the solar wind still contained features which impacted the Earth's magnetosphere and caused geomagnetic disturbances. Recurrent corotating interaction regions (CIRs) and associated high-speed solar wind streams (HSSs) are typically associated with the declining phase of the solar cycle and were a regular feature of the solar wind during the most recent solar minimum. Here we compare and contrast strong and weak HSSs in the solar wind and their subsequent effect within the Earth's magnetosphere. We find significant differences between strong and weak HSS effects in the plasmasphere, in the ion and electron plasma sheets, and in the outer electron radiation belt. A density-temperature description of the outer radiation belt is shown to shed light on why the radiation belt flux is observed to return at a higher level after the arrival of strong HSSs than before strong HSSs and why the flux is observed to return at a lower level after the arrival of weak HSSs than before weak HSSs.