GEM: Simulation Studies of Plasma Redistribution in the Ionosphere and Plasma Supply to the Magnetosphere in Geomagnetic Active Periods

GEM：地磁活跃期电离层等离子体重新分布和磁层等离子体供应的模拟研究

• 批准号: 1702134
• 负责人: Jiannan Tu
• 金额: $ 27.9万
• 依托单位: University of Massachusetts Lowell
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-01 至 2020-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1702134&HistoricalAwards=false
• 关键词: GEM; Simulation; Studies; Plasma; Redistribution

This project is focused on investigating how changes in the structure of the upper levels of the atmosphere can lead to changes in the plasma flowing out into the outer space. During periods of significant space weather the circulation of plasma in the upper atmosphere can be dramatically changed, resulting in high density regions flowing over the polar cap that can lead to enhanced outflow of plasma flowing out along magnetic field lines into outer space. These changes can impact radio communications through the ionosphere and may cause significant errors in positions derived from satellite based navigation systems. The investigators will address this important topic through the development of a numerical model. This model will be able to address how the outflow plasma relates to these density enhancements. Success in modeling these interactions could potentially lead to improved numerical models for forecasting space weather. In addition, this investigation will support training of a graduate student in computer programming and data analysis techniques. A major focus of this investigation will be simulation studies of plasma redistribution associated with the storm enhanced density (SED) and its possible counterpart plasmaspheric plume, polar cap tongues and patches, and enhanced ion outflow associated with such plasma redistribution during geomagnetic active times. The objective of the proposed studies is to expand the Dynamic Fluid Kinetic (DyFK) model to simultaneously follow multiple drifting individual flux tubes for simulating global plasma transport; to quantitatively understand physical processes that cause plasma redistribution and ion outflow; to provide quantitative measure of global ion outflow fluxes of multiple species necessary to understand effects of ionospheric plasma supply on the magnetospheric dynamics.

该项目的重点是研究大气层上层结构的变化如何导致流入外层空间的等离子体发生变化。 在显著的空间天气期间，高层大气中的等离子体的循环可以显著地改变，导致高密度区域流过极冠，这可以导致等离子体沿着沿着磁场线流出到外层空间中的增强的流出。 这些变化可能影响通过电离层的无线电通信，并可能导致基于卫星的导航系统得出的位置出现重大误差。 研究人员将通过开发一个数值模型来解决这一重要问题。 这个模型将能够解决如何流出等离子体与这些密度增强。 对这些相互作用进行建模的成功可能会改进预测空间天气的数值模型。 此外，这项调查将支持培训一名计算机编程和数据分析技术的研究生。本次调查的一个主要重点将是等离子体再分布与风暴增强密度（SED）和其可能的对应plasmaspheric羽流，极地帽舌和补丁，和增强的离子外流与这种等离子体再分布在地磁活跃时间的模拟研究。拟议研究的目标是扩展动态流体动力学（DyFK）模型，以同时跟踪多个漂移的单个通量管，模拟全球等离子体传输;定量了解导致等离子体重新分布和离子外流的物理过程;提供了解电离层等离子体供应对磁层动力学影响所需的多种全球离子外流通量的定量测量。

项目成果

On the Momentum Transfer From Polar to Equatorial Ionosphere

• DOI: 10.1029/2019ja026760
• 发表时间: 2019-07
• 期刊: Journal of Geophysical Research: Space Physics
• 作者: J. Tu;P. Song

Parallel propagation and damping of electromagnetic waves in a partially ionized plasma with multiple species

多物质部分电离等离子体中电磁波的并行传播和阻尼

• DOI: 10.1063/1.5053119
• 发表时间: 2018
• 期刊: Physics of Plasmas
• 影响因子: 2.2
• 作者: Huang, Yifan;Tu, Jiannan;Song, Paul
• 通讯作者: Song, Paul