Effect of kinetic Alfven waves on electron transport in an ion-scale flux rope
Effect of kinetic Alfven waves on electron transport in an ion-scale flux rope
复制标题
动力学阿尔文波对离子级通量绳中电子传输的影响
DOI：
10.1088/0256-307x/35/11/119401
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发表时间：
2018
影响因子：
3.5
通讯作者：
Han Jinpeng
中科院分区：
文献类型：
--
作者：
Tang Binbin;Li Wenya;Wang Chi;Dai Lei;Han Jinpeng
磁层多尺度使命研究了地球磁层顶离子尺度通量绳中动力学阿尔文波（KAWs）引起的电子输运。在整个磁通绳中观察到约90俯仰角的明显电子脱落，其中确定了强烈的KAWs。KAWs可以通过波平行电场和磁镜力有效地捕获电子，使电子经历朗道共振并被输运到更多的场取向方向。从波分析，这是在良好的协议与直接的电子分布的俯仰角测量的被困电子的俯仰角范围估计。新形成的束状电子分布是不稳定的，并激发哨声波，在观察中发现。我们认为，KAWs可能是负责通过这种传输过程的等离子体耗尽内的磁通绳，从而负责形成一个典型的磁通绳。
At the Earth's magnetopause, the electron transport due to kinetic Alfvén waves (KAWs) is investigated in an ion-scale flux rope by the Magnetospheric Multiscale mission. Clear electron dropout around 90 pitch angle is observed throughout the flux rope, where intense KAWs are identified. The KAWs can effectively trap electrons by the wave parallel electric field and the magnetic mirror force, allowing electrons to undergo Landau resonance and be transported into more field-aligned directions. The pitch angle range for the trapped electrons is estimated from the wave analysis, which is in good agreement with direct pitch angle measurements of the electron distributions. The newly formed beam-like electron distribution is unstable and excites whistler waves, as revealed in the observations. We suggest that KAWs could be responsible for the plasma depletion inside a flux rope by this transport process, and thus be responsible for the formation of a typical flux rope.