Enhancement of the Jovian Magnetospheric Plasma Circulation Caused by the Change in Plasma Supply From the Satellite Io
Enhancement of the Jovian Magnetospheric Plasma Circulation Caused by the Change in Plasma Supply From the Satellite Io
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卫星Io等离子体供应变化引起的木星磁层等离子体环流增强
DOI：
10.1029/2018ja025316
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发表时间：
2018
期刊：
影响因子：
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通讯作者：
Sakanoi T.
中科院分区：
文献类型：
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作者：
Tsuchiya F.;Yoshioka K.;Kimura T.;Koga R.;Murakami G.;Yamazaki A.;Kagitani M.;Tao C.;Suzuki F.;Hikida R.;Yoshikawa I.;Kasaba Y.;Kita H.;Misawa H.;Sakanoi T.
最内侧的伽利略卫星，木卫一，为木星的磁层提供了大量的火山气体。木星的快速旋转和向外输送的电离气体是形成一个巨大的旋转主导磁层的原因。来自卫星的等离子体供应在描述木星磁层的特性方面起着关键作用。事实上，在2015年初，使用从Hisaki卫星上的极紫外光谱仪获得的木卫一等离子体环的连续数据集，发现了由木卫一火山爆发引起的内磁层等离子体种群的显着变化。木卫一等离子体环径向分布的时间演化表明，从木星通过8 RJ向外输送的等离子体增强了约2个月（从2015年1月底到4月初）。在此期间，强烈的短暂极光增亮-代表磁层外部的瞬时能量释放-经常发生。短暂的极光增亮伴随着等离子体环中离子亮度的明确零星增强，表明能量从磁层外部快速向内传输，从而增强了内磁层中的热电子数量。这显然表明，内磁层中等离子体源的变化影响了旋转主导磁层中质量和能量的大尺度径向循环。
The innermost Galilean satellite, Io, supplies a large amount of volcanic gasses to the Jovian magnetosphere. The fast rotation of Jupiter and the outward transport of ionized gasses are responsible for forming a huge and rotationally dominant magnetosphere. The plasma supply from the satellite has a key role in the characterization of the Jovian magnetosphere. In fact, significant variations of the plasma population in the inner magnetosphere caused by the volcanic eruptions in Io were found in early 2015, using a continuous data set of the Io plasma torus obtained from an extreme ultraviolet spectroscope onboard the Hisaki satellite. The time evolution of the Io plasma torus radial distribution showed that the outward transport of plasma through 8RJfrom Jupiter was enhanced for approximately 2 months (from the end of January to the beginning of April 2015). Intense short‐lived auroral brightenings––which represent transient energy releases in the outer part of the magnetosphere—occurred frequently during this period. The short‐lived auroral brightenings accompanied well‐defined sporadic enhancements of the ion brightness in the plasma torus, indicating a rapid inward transport of energy from the outer part of the magnetosphere and the resultant enhancement of hot electron population in the inner magnetosphere. This evidently shows that the change in a plasma source in the inner magnetosphere affects a large‐scale radial circulation of mass and energy in a rotationally dominant magnetosphere.