Observational evidence of electron pitch angle scattering driven by ECH waves
Observational evidence of electron pitch angle scattering driven by ECH waves
复制标题
DOI：
10.1002/2014gl061927
复制
发表时间：
2014-11
影响因子：
5.2
通讯作者：
S. Kurita;Y. Miyoshi;C. Cully;V. Angelopoulos;O. Contel;M. Hikishima;H. Misawa
中科院分区：
文献类型：
--
作者：
S. Kurita;Y. Miyoshi;C. Cully;V. Angelopoulos;O. Contel;M. Hikishima;H. Misawa
利用从亚暴期间事件时间历史和大尺度相互作用中获得的等离子体波和电子数据，我们在速度分布函数（VDF）中显示了由静电回旋谐波（ECH）驱动的电子俯仰角散射的特征。哨声模式波的扩散曲线被用作代理，以识别由于波粒相互作用而引起的VDF变化。我们确认，VDF的形状以及符合哨声模式波的扩散曲线时，单独的哨声模式合唱是活跃的。另一方面，我们发现的VDF的形状偏离扩散曲线在低的俯仰角时，ECH波是活跃的合唱波失活。这一结果为ECH波引起的电子俯仰角散射提供了观测支持，并表明ECH波有助于产生漫射极光。
Using the plasma wave and electron data obtained from Time History of Events and Macroscale Interactions during Substorms, we show a signature of electron pitch angle scattering driven by Electrostatic Cyclotron Harmonic (ECH) waves in the velocity distribution function (VDF). The diffusion curve of whistler mode waves is used as a proxy to identify changes in VDFs due to wave‐particle interactions. We confirm that the shape of the VDF well agrees with the diffusion curve of whistler mode waves when whistler mode chorus alone is active. On the other hand, we find that the shape of the VDF deviates from the diffusion curves at low pitch angles when ECH waves are active following the inactivation of chorus waves. The result is observational support for electron pitch angle scattering caused by ECH waves and suggests that ECH waves can contribute to generation of diffuse auroras.