AGS-PRF: An Observational-based Modeling Approach for Solar Energetic Particle Access to the Equatorial Inner Magnetosphere

关于太阳高能粒子（SEP）如何与地磁场相互作用，仍然存在许多问题。这些粒子在爆炸性事件之后流入地磁环境，例如耀斑和来自太阳的日冕物质抛射。粒子可能被困在地磁场中，这些粒子的能量以及地球空间环境，包括当前系统，影响它们穿透的距离。这个博士后奖学金支持这一主题的研究，这对于了解空间天气对卫星等敏感系统的影响非常重要，这些系统可能会被SEP损坏。除了支持早期的职业科学家，该项目包括创建一个空间天气演示，将用于教育推广events.A全面的基于观测的建模方法将被用来提供统计的见解，什么过程影响SEP进入地磁场。该研究利用了20个太阳高能粒子事件，这些事件发生在2013年1月至2017年12月的一系列风暴和非风暴条件下，并且至少用两颗卫星进行测量。使用多航天器方法，将同时在各种径向距离、能量和一系列磁当地时间上对观测结果进行检查。利用在内磁层观测到的太阳质子的东西向通量各向异性，有可能测量近赤道区域的粒子截止。他们将把现场测量的能量和方向相关截止值与通过使用粒子跟踪模型计算的地磁截止值进行比较。使用Tsyganenko 2005年的粒子追踪模型，他们将确定哪些电流系统有助于抑制地磁截止。该奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

Many questions remain about how solar energetic particles (SEPs) interact with the geomagnetic field. These particles stream into the geomagnetic environment following explosive events, such as flares and coronal mass ejections from the Sun. Particles may become trapped in the geomagnetic field and the energy of these particles as well as the geospace environment, including current systems, affect how far they penetrate. This postdoctoral fellowship supports research on this topic, which is important to understanding space weather impacts to sensitive systems like satellites, which can be damaged by SEPs. In addition to supporting an early career scientist, this project includes the creation of a space weather demonstration that will be used in educational outreach events.A comprehensive observational-based modeling approach will be employed to provide statistical insights into what processes affect SEP access into the geomagnetic field. The study utilizes 20 solar energetic particle events, which occur during a range of storm and non-storm conditions, from January 2013-December 2017, and which are measured with at least two satellites. Using a multi-spacecraft approach, the observations will be examined at a wide variety of radial distances, energies, and at a range of magnetic local times simultaneously. Utilizing the east-west directional flux anisotropy for solar protons observed in the inner-magnetosphere it is possible to measure particle cutoffs in the near-equatorial region. They will compare the energy and directional dependent cutoffs measured in-situ to the geomagnetic cutoffs calculated via the use of particle tracking models. Using the Tsyganenko 2005 particle tracing model they will determine which current systems contribute to suppressed geomagnetic cutoffs.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.