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还有许多问题。这些粒子在太阳耀斑和日冕物质抛射等爆炸事件发生后流入地磁环境。粒子可能会被困在地磁场中，这些粒子的能量以及地球空间环境，包括电流系统，都会影响它们穿透的距离。该博士后奖学金支持该主题的研究，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。除了支持一名早期职业科学家之外，该项目还包括创建一个空间天气演示，该演示将用于教育推广活动。一个全面的基于观测的建模方法将被用来提供统计上的见解，哪些过程会影响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，并由至少两颗卫星测量。使用多航天器的方法，观测结果将同时在各种径向距离、能量和磁地方时范围内进行检查。利用在内磁层观测到的太阳质子的东西向通量各向异性，可以测量近赤道地区的粒子截止点。他们将把原位测量的能量和方向相关截止点与通过使用粒子跟踪模型计算的地磁截止点进行比较。利用Tsyganenko 2005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。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

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.