Graham D B, Khotyaintsev Yu V, Vaivads A, Norgren C, André M, Webster J M, Burch J L, Lindqvist P-A, Ergun R E, Torbert R B, Paterson W R, Gershman D J, Giles B L, Magnes W, Russell C T
Swedish Institute of Space Physics, Uppsala SE-75121, Sweden.
Department of Physics and Astronomy, Uppsala University, Uppsala SE-75121, Sweden.
Phys Rev Lett. 2017 Jul 14;119(2):025101. doi: 10.1103/PhysRevLett.119.025101. Epub 2017 Jul 13.
During a magnetopause crossing the Magnetospheric Multiscale spacecraft encountered an electron diffusion region (EDR) of asymmetric reconnection. The EDR is characterized by agyrotropic beam and crescent electron distributions perpendicular to the magnetic field. Intense upper-hybrid (UH) waves are found at the boundary between the EDR and magnetosheath inflow region. The UH waves are generated by the agyrotropic electron beams. The UH waves are sufficiently large to contribute to electron diffusion and scattering, and are a potential source of radio emission near the EDR. These results provide observational evidence of wave-particle interactions at an EDR, and suggest that waves play an important role in determining the electron dynamics.
在磁层顶穿越期间，磁层多尺度航天器遇到了不对称重联的电子扩散区（EDR）。该EDR的特征是存在非旋电子束以及垂直于磁场的新月形电子分布。在EDR与磁鞘流入区域的边界处发现了强烈的上混杂（UH）波。这些UH波由非旋电子束产生。UH波足够强大，可促成电子扩散和散射，并且是EDR附近无线电发射的潜在来源。这些结果提供了EDR处波粒相互作用的观测证据，并表明波在确定电子动力学方面起着重要作用。
