GEM: Integration of Plasma Sheet Bubbles into Modeling of the Inner Magnetosphere

GEM：将等离子体片状气泡集成到内部磁层建模中

• 批准号: 1938599
• 负责人: William Cramer
• 金额: $ 41.48万
• 依托单位: University of New Hampshire
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-12-15 至 2024-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1938599&HistoricalAwards=false
• 关键词: GEM; Integration; Plasma; Sheet; Bubbles

Space weather results from changes in the solar wind and how it impacts the near-Earth space environment. Plasma injections from the outer region of the magnetosphere (known as the magnetotail) bring relativistic particles into the inner regions of the magnetosphere. Understanding this process is important for building predictive models of space weather – to predict, for instance, levels of radiation and relativistic particles that can damage spacecraft, provide health risks to astronauts, disrupt radio communications, and cause power grid blackouts. The results of this project have direct applications in space weather models, and will thus contribute to the goals set out in the National Space Weather Action Plan. A newly-coupled global magnetosphere-inner magnetosphere model (OpenGGCM-CIMI) will be used to investigate the integration of plasma sheet injections into the inner magnetosphere region. The work will focus on the transient injections associated with regions of low flux tube entropy known as bubbles. The new model will provide novel capabilities for the analysis of plasma sheet injections, including: (1) the ability to track plasma sheet injections from birth in the plasma sheet to dissolution into the inner magnetosphere, (2) the preservation of pitch angle distribution information to track the position and evolution of the injection, and (3) the inclusion of the entire inner magnetosphere particle energy spectrum and most loss processes (to provide realistic behavior). Satellite data will be used to validate model results. Data from the Van Allen Probes will be used to identify and characterize injections in the ring current region. Data from other spacecraft (THEMIS, GOES, Cluster, and MMS) will be used to analyze these bubble-driven flows in the plasma sheet region. Where possible, conjunctions of spacecraft will be used to connect the observations.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.

空间天气是太阳风变化及其如何影响近地空间环境的结果。等离子体从磁层的外部区域（称为磁尾）注入，将相对论性粒子带入磁层的内部区域。了解这一过程对于建立空间天气预测模型非常重要-例如，预测可能损坏航天器的辐射和相对论粒子的水平，给宇航员带来健康风险，中断无线电通信，并导致电网停电。该项目的成果可直接应用于空间气象模型，因此将有助于实现《国家空间气象行动计划》所列目标。一个新的全球磁层-内磁层耦合模型（OpenGGCM-CIMI）将被用来研究等离子体片注入到内磁层区域的整合。这项工作将集中在瞬态注入与低通量管熵称为气泡的区域。新模型将为等离子体片注入分析提供新的功能，包括：（1）跟踪等离子体片注入从等离子体片中的诞生到溶解到内磁层中的能力，（2）保存俯仰角分布信息以跟踪注入的位置和演变，以及（3）包括整个内磁层粒子能谱和大多数损失过程（以提供真实的行为）。卫星数据将用于验证模型结果。来自货车艾伦探针的数据将用于识别和表征环电流区域中的注入。来自其他航天器（THEMIS，GOES，Cluster和MMS）的数据将用于分析等离子体片区域中的气泡驱动流。在可能的情况下，将使用航天器的连接来连接观测结果。该奖项反映了NSF的法定使命，并被认为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来支持。