In this study we examine the ability of protons of solar origin to access the near‐equatorial inner magnetosphere. Here we examine four distinct solar proton events from 20–200 MeV, concurrent with both quiet time and storm time conditions using proton data from the ACE satellite in the solar wind upstream of Earth and data from the Relativistic Electron Proton Telescope (REPT) instrument aboard Van Allen Probes. We examine the direct flux correspondence between interplanetary space and the inner magnetosphere. Small substructures in interplanetary space are observable in the REPT flux profiles, which can penetrate down to L values of ≤4. Furthermore, there are orbit‐to‐orbit variations in the west‐to‐east anisotropic flux ratios. The anisotropic flux ratios are used as a proxy for cutoff energies and display cutoff variations with L shell and energy. The dependence of the anisotropic flux ratio on Dst values is shown. The results paint a picture of highly dynamic spatial and temporal proton cutoff rigidities in the near‐equatorial inner magnetosphere.

中文翻译：

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太阳能质子进入近赤道内磁层的途径

在这项研究中，我们研究了太阳起源的质子进入赤道内部磁层的能力。在这里，我们使用来自地球上游太阳风中ACE卫星的质子数据和来自相对论电子质子望远镜（REPT）的数据，研究了20-200 MeV的四个不同的太阳质子事件，同时还涉及了安静时间和风暴时间情况。 Van Allen Probes。我们研究了行星际空间与内部磁层之间的直接通量对应关系。在REPT通量剖面中可以观察到行星际空间中的小子结构，这些子结构可以向下渗透到≤的L值4.此外，西向东各向异性通量比在轨道间也有变化。各向异性通量比用作截止能量的代理，并显示截止壳随L壳和能量的变化。示出了各向异性通量比对Dst值的依赖性。结果描绘了近赤道内磁层中高度动态的空间和时间质子截止刚度。