The two Van Allen Probes simultaneously recorded a coherently modulated quasiperiodic (QP) emission that persisted for 3 h. The magnetic field pulsation at the locations of the two satellites showed a substantial difference, and their frequencies were close to but did not exactly match the repetition frequency of QP emissions for most of the time, suggesting that those coherent QP emissions probably originated from a common source, which then propagated over a broad area in the magnetosphere. The QP emissions were amplified by local anisotropic electron distributions, and their large‐scale amplitudes were modulated by the plasma density. A novel observation of this event is that chorus waves at frequencies above QP emissions exhibit a strong correlation with QP emissions. Those chorus waves intensified when the QP emissions reach their peak frequency. This indicates that embryonic QP emissions may be critical for its own intensification as well as chorus waves under certain circumstances. A Low‐Earth‐Orbit POES satellite observed enhanced energetic electron precipitation in conjunction with the Van Allen Probes, providing direct evidence that QP emissions precipitate energetic electrons into the atmosphere. This scenario is quantitatively confirmed by our quasilinear diffusion simulation results.

中文翻译：

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准周期发射强度及其对高能电子沉淀的多点观测

两个Van Allen探针同时记录了相干调制的拟周期性（QP）发射，该发射持续了3 h。两颗卫星所处位置的磁场脉动显示出很大的差异，并且它们的频率在大多数时间内接近但与QP发射的重复频率不完全匹配，这表明这些相干的QP发射可能源自共同的源，然后在磁层的广阔区域传播。QP发射被局部各向异性电子分布放大，其大幅度振幅受到等离子体密度的调节。对这一事件的新颖观察是，高于QP发射频率的合唱波与QP发射具有很强的相关性。当QP发射达到峰值频率时，这些合唱波会增强。这表明在某些情况下，胚胎QP排放可能对其自身的强化以及合唱波至关重要。低地球轨道POES卫星与Van Allen探针一起观测到高能电子沉淀增强，这提供了直接的证据证明QP发射将高能电子沉淀到大气中。我们的准线性扩散模拟结果定量地证实了这种情况。提供了直接的证据证明QP排放将高能电子沉淀到大气中。我们的准线性扩散模拟结果定量地证实了这种情况。提供了直接的证据证明QP排放将高能电子沉淀到大气中。我们的准线性扩散模拟结果定量地证实了这种情况。