Radiation belt electrons have a complicated relationship with geomagnetic activity. We select electron measurements from 7 years of DEMETER and 6 years of Van Allen Probes data during geomagnetic storms to conduct statistical analysis focusing on the correlation between electron flux and Dst index. We report, for the first time, an upper limit of electron fluxes observed by both satellites throughout the inner and outer belts across a wide energy range from ∼100s keV to multi‐MeV. The upper flux limit is determined at different L's and energies, for example, 1.9 × 10⁷/cm²‐s‐sr‐MeV at 470 keV at L = 1.5 and 3.6 × 10⁵/cm²‐s‐sr‐MeV at 3.4 MeV at L = 4 (Van Allen Probes). We present the energy spectra of the electron flux upper limit at different L shells and find the measured upper flux limit to be at least three times higher than the predicted flux from the AE8/AE9 models, although the spectral shape is remarkably similar. We show that the average flux with an applied time lag is better correlated with the Dst index and that the time lag optimizing the correlation coefficient is larger at lower L and at higher energies. These findings present the underlying challenges to model the dynamic variation of relativistic electrons in the inner magnetosphere and are important information for space weather considerations.

中文翻译：

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辐射带中观察到的电子通量的上限

辐射带电子与地磁活动有复杂的关系。我们从地磁暴期间7年的DEMETER和6年的Van Allen Probes数据中选择电子测量值，以便进行统计分析，重点是电子通量和Dst指数之间的相关性。我们首次报告了在从约100s keV到多MeV的宽能量范围内，两颗卫星在整个内，外带观测到的电子通量的上限。通量上限是根据不同的L和能量确定的，例如，在L  = 1.5时的470 keV时为1.9×10 ⁷ / cm ² -s-sr-MeV和3.6×10 ⁵ / cm ² -s- sr-MeV MeV在3.4 MeV在L = 4（范艾伦探针）。我们给出了不同L壳层的电子通量上限的能谱，并发现测得的通量上限至少比AE8 / AE9模型的预测通量高三倍，尽管光谱形状非常相似。我们表明，具有一定时滞的平均通量与Dst指数具有更好的相关性，并且优化相关系数的时滞在较低的L和较高的能量下较大。这些发现为模拟相对磁电子在内部磁层中的动态变化提出了潜在的挑战，并且是考虑空间天气的重要信息。