We report global dayside observation of Pc4–5 wave at the late recovery phase of a magnetic storm from seven satellites. Oscillations lasted for 15 hr and revealed the wave appearance before the substorm onset. The continuous observation showed that substorm injections did not affect the wave behavior, and all the wave parameters change was caused by magnetospheric plasma recovery after a magnetic storm. The wave was identified as a second harmonic poloidal Alfvén wave propagating westward with a high azimuthal wave number (|m| ∼ 210) and coupled with 100 keV protons through the drift-bounce resonance. A large radial gradient of phase space density was an energy source for the wave.

中文翻译：

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亚暴前持久极向超低频波的多航天器观测

我们报告了来自七颗卫星的磁暴后期恢复阶段 Pc4-5 波的全球日侧观测。振荡持续了 15 小时，并揭示了亚暴开始前的波浪外观。连续观测表明，亚暴注入并未影响波浪行为，所有波浪参数的变化都是由磁暴后磁层等离子体恢复引起的。该波被确定为向西传播的二次谐波极向阿尔芬波，具有高方位波数 (| m | ∼ 210)，并通过漂移反弹共振与 100 keV 质子耦合。相空间密度的大径向梯度是波的能量来源。