The Kelvin‐Helmholtz Instability (KHI) is thought to be an important driver of mass and momentum transfer from the solar wind to the Earth's magnetosphere. We present observations from NASA's Magnetospheric Multiscale mission of ion acoustic‐like waves associated with turbulence during the KHI interval on 8 September 2015. These parallel electrostatic waves are nonlinear, can have amplitudes in excess of 100 mV/m, and may be associated with a field‐aligned potential drop. We perform a survey of all vortices in the 8 September 2015 event, investigating the occurrence of electrostatic waves below the ion plasma frequency. We find that they tend to occur in the turbulent region in the middle of the KHI vortices, independent of the presence of compressed or intermittent currents. This suggests that the waves occur in the presence of plasma mixing in the vortex region and that they may play a part in the overall turbulent dissipation process.

中文翻译：

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与开尔文-亥姆霍兹不稳定性的湍流等离子体混合相关的平行静电波

开尔文-亥姆霍兹不稳定性（KHI）被认为是质量和动量从太阳风传递到地球磁层的重要驱动力。我们从2015年9月8日KHI间隔期间的NASA的磁层多尺度任务中获取与湍流相关的离子声波的观测结果。这些平行的静电波是非线性的，幅度可能超过100 mV / m，并且可能与磁场对准的电位降。我们对2015年9月8日事件中的所有漩涡进行了调查，调查了低于离子等离子体频率的静电波的发生。我们发现，它们倾向于出现在KHI涡旋中部的湍流区域中，而与压缩或间歇性电流的存在无关。