Electron Bernstein waves driven by electron crescents near the electron diffusion region
Electron Bernstein waves driven by electron crescents near the electron diffusion region
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DOI：
10.1038/s41467-019-13920-w
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发表时间：
2020-01
影响因子：
16.6
通讯作者：
Weijin Li;Weijin Li;Weijin Li;D. Graham;Y. Khotyaintsev;A. Vaivads;Mats André;Kyoung-Ik Min;Kaijun Liu;B. B. Tang-B.;Chunmiao Wang;K. Fujimoto;C. Norgren;S. Toledo‐Redondo;S. Toledo‐Redondo;P. Lindqvist;R. Ergun;R. Torbert;A. Rager;A. Rager;J. Dorelli;D. Gershman;D. Gershman;B. Giles;B. Lavraud;F. Plaschke;W. Magnes;O. Contel;C. Russell;J. Burch
中科院分区：
文献类型：
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作者：
Weijin Li;Weijin Li;Weijin Li;D. Graham;Y. Khotyaintsev;A. Vaivads;Mats André;Kyoung-Ik Min;Kaijun Liu;B. B. Tang-B.;Chunmiao Wang;K. Fujimoto;C. Norgren;S. Toledo‐Redondo;S. Toledo‐Redondo;P. Lindqvist;R. Ergun;R. Torbert;A. Rager;A. Rager;J. Dorelli;D. Gershman;D. Gershman;B. Giles;B. Lavraud;F. Plaschke;W. Magnes;O. Contel;C. Russell;J. Burch
磁层多尺度（MMS）航天器在地球磁层顶遇到不对称磁重联的电子扩散区（EDR）。 EDR 的特点是中性线两侧的电子速度分布呈陀螺变化。 EDR 内及其附近的磁重联会产生各种类型的等离子体波。在这里，我们报告了霍尔电流反转的电子尺度边界处的大振幅电子伯恩斯坦波（EBW）。流出电子的有限回旋半径效应产生新月形渐转电子分布，从而驱动电子束。 EBW 向中央 EDR 传播。 EBW 的幅度足够大，足以使 EDR 周围的电子热化和扩散。 EBW 有助于 EDR 附近霍尔电流反转的电子尺度边界的交叉场扩散。
The Magnetospheric Multiscale (MMS) spacecraft encounter an electron diffusion region (EDR) of asymmetric magnetic reconnection at Earth’s magnetopause. The EDR is characterized by agyrotropic electron velocity distributions on both sides of the neutral line. Various types of plasma waves are produced by the magnetic reconnection in and near the EDR. Here we report large-amplitude electron Bernstein waves (EBWs) at the electron-scale boundary of the Hall current reversal. The finite gyroradius effect of the outflow electrons generates the crescent-shaped agyrotropic electron distributions, which drive the EBWs. The EBWs propagate toward the central EDR. The amplitude of the EBWs is sufficiently large to thermalize and diffuse electrons around the EDR. The EBWs contribute to the cross-field diffusion of the electron-scale boundary of the Hall current reversal near the EDR.