In this study we investigate two distinct loss mechanisms responsible for the rapid dropouts of radiation belt electrons by assimilating data from Van Allen Probes A and B and Geostationary Operational Environmental Satellites (GOES) 13 and 15 into a 3‐D diffusion model. In particular, we examine the respective contribution of electromagnetic ion cyclotron (EMIC) wave scattering and magnetopause shadowing for values of the first adiabatic invariant μ ranging from 300 to 3,000 MeV G⁻¹. We inspect the innovation vector and perform a statistical analysis to quantitatively assess the effect of both processes as a function of various geomagnetic indices, solar wind parameters, and radial distance from the Earth. Our results are in agreement with previous studies that demonstrated the energy dependence of these two mechanisms. We show that EMIC wave scattering tends to dominate loss at lower L shells, and it may amount to between 10%/hr and 30%/hr of the maximum value of phase space density (PSD) over all L shells for fixed first and second adiabatic invariants. On the other hand, magnetopause shadowing is found to deplete electrons across all energies, mostly at higher L shells, resulting in loss from 50%/hr to 70%/hr of the maximum PSD. Nevertheless, during times of enhanced geomagnetic activity, both processes can operate beyond such location and encompass the entire outer radiation belt.

中文翻译：

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通过数据同化量化EMIC波散射和外电子辐射带中的磁更年期阴影效应

在这项研究中，我们通过将Van Allen探针A和B以及地球静止运行环境卫星（GOES）13和15的数据吸收到3D扩散模型中，研究了造成辐射带电子快速消失的两种不同的损失机制。特别是，我们检查了第一绝热不变量μ的值（从300到3,000 MeV G ^-1）的电磁离子回旋加速器（EMIC）波散射和磁更年期阴影的各自贡献。。我们检查创新载体并进行统计分析，以定量评估这两个过程的影响，这些过程是各种地磁指数，太阳风参数以及与地球的径向距离的函数。我们的结果与以前的研究一致，后者证明了这两种机制的能量依赖性。我们表明，EMIC波散射趋向于在较低的L壳层上占主导地位，对于固定的第一和第二个壳层，其在所有L壳层上的相空间密度（PSD）最大值的总和可能在10％/ hr到30％/ hr之间绝热不变量。另一方面，发现更年期阴影会耗尽所有能量上的电子，主要是在较高的L下壳，导致最大PSD损失从50％/小时到70％/小时。然而，在地磁活动增强的时期，这两个过程都可以在该位置之外进行操作，并覆盖整个外部辐射带。