We present a novel technique to analyze VDF, which allows to capture their fine structure including wave‐particles resonances. By applying the technique to magnetospheric multiscale (MMS) data, the simultaneous observation of characteristic three‐dimensional (3‐D) signatures in the electron velocity distribution function (VDF) and intense quasi‐monochromatic waves in the terrestrial magnetosheath is investigated. The intense wave packets are characterized and modeled analytically as quasi‐parallel circularly polarized whistler waves and applied to a test‐particle simulation in view of gaining insight into the signature of the wave‐particle resonances in velocity space. Both the Landau and the cyclotron resonances were evidenced in the test‐particle simulations. The location and general shape of the test‐particle signatures do account for the observations, but the finer details, such as the symmetry of the observed signatures, are not matched, indicating either the limits of the test‐particle approach or a more fundamental physical mechanism not yet grasped. Finally, it is shown that the energization of the electrons in this precise resonance case cannot be diagnosed using the moments of the distribution function, as done with the classical E · J “dissipation” estimate.

中文翻译：

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共振惠斯勒-电子相互作用：MMS观察与测试颗粒模拟

我们提出了一种分析VDF的新技术，该技术可以捕获VDF的精细结构，包括波粒共振。通过将该技术应用于磁层多尺度（MMS）数据，研究了同时观测电子速度分布函数（VDF）中的特征性三维（3D）签名和地面磁热的强烈准单色波的现象。为了深入了解速度空间中波粒共振的特征，将强波包表征为准平行圆极化惠斯勒波并进行分析建模，并将其应用于测试粒子模拟。测试粒子模拟证明了朗道共振和回旋加速器共振。测试粒子签名的位置和总体形状确实说明了观察结果，但是更细微的细节（例如观察到的签名的对称性）不匹配，表明测试粒子方法的局限性或更基本的物理意义机制尚未掌握。最后，证明了在这种精确的共振情况下，电子的通电无法使用分布函数的矩来诊断，就像经典的方法一样。E  ·  J “耗散”估计。