GEM: The Entry of Ions into and Population of the Magnetosphere During Quiet Times

GEM：安静时期离子进入磁层和填充

• 批准号: 1003841
• 负责人: Vahe Peroomian
• 金额: $ 27.3万
• 依托单位: University of California-Los Angeles
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-08-01 至 2014-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1003841&HistoricalAwards=false
• 关键词: GEM; Entry; Ions; into; Population

This project will map the entry and subsequent transport of plasma into Earth's magnetosphere and magnetotail. The research will be conducted by tracing the paths taken by billions of ions originating in the solar wind and in the ionosphere. The particle tracing will be done using the time-dependent electric and magnetic fields calculated with a global magnetohydrodynamics (MHD) model of the magnetosphere. The MHD model will be driven by observed data (velocity, density, and the interplanetary magnetic field) from the solar wind. The project will address the following questions: 1. Where do the solar wind ions that reach the plasma sheet and the ring current enter the magnetosphere? 2. What is the role of the Kelvin-Helmholtz instability in ion access to the magnetosphere? 3. What is the cause of the observed dawn-dusk asymmetry in ion entry and ion distributions in the magnetotail? 4. What is the spatial distribution in the magnetotail of the ions originate from the ionosphere? And 5. What is the relative abundance of ionospheric and solar wind ions as a function of solar wind parameters?The project will concentrate on plasma entry during quiet magnetic conditions. Understanding the entry and distribution of ions during quiet times will provide a baseline for understanding how the system changes during magnetically disturbed times such as during magnetic storms. The transition from quiet to disturbed magnetic conditions is an important consideration in understanding space weather events.

该项目将绘制等离子体进入地球磁层和磁尾以及随后的传输情况。这项研究将通过追踪源自太阳风和电离层的数十亿离子的路径来进行。粒子追踪将利用磁层全球磁流体动力学模型计算的随时间变化的电场和磁场进行。 MHD模型将由来自太阳风的观测数据（速度、密度和行星际磁场）驱动。该项目将解决以下问题：1。到达等离子体片和环电流的太阳风离子在哪里进入磁层？ 2.开尔文-亥姆霍兹不稳定性在离子进入磁层中的作用是什么？ 3.在磁尾的离子进入和离子分布中观察到的黎明和黄昏不对称的原因是什么？ 4.起源于电离层的离子在磁尾的空间分布是什么？和5.电离层和太阳风离子的相对丰度是多少，作为太阳风参数的函数？该项目将专注于在安静的磁场条件下进入等离子体。 了解安静时期离子的进入和分布将为了解系统在磁干扰时期（如磁暴期间）如何变化提供基线。 从平静到扰动磁场条件的转变是了解空间气象事件的一个重要考虑因素。