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

该项目将绘制等离子体进入地球磁层和磁尾的情况以及随后的传输情况。这项研究将通过追踪起源于太阳风和电离层的数十亿离子的路径来进行。粒子追踪将使用由磁层的全球磁流体动力学(MHD)模型计算的随时间变化的电场和磁场来完成。MHD模型将由太阳风的观测数据(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.观测到的离子进入和磁尾中离子分布的黎明-黄昏不对称的原因是什么？4.来自电离层的离子在磁尾的空间分布是什么？电离层离子和太阳风离子的相对丰度与太阳风参数的关系如何？该项目将集中在静磁条件下的等离子体进入。了解静止期离子的进入和分布将为理解系统在磁扰动期(如磁暴期间)的变化提供基线。在理解空间气象事件时，从静磁条件到扰动磁力条件的转变是一个重要的考虑因素。

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.