GEM: Global Modeling of the Consequences of High-latitude Merging Processes at the Magnetopause

该项目将调查高纬度日侧磁层顶磁合并过程(重联)的大尺度特性和后果。它将研究高纬度重联对从太阳风到磁层的质量、能量和动量传输的贡献。特别是，调查的重点将是确定磁重联在维持和偶尔增厚低纬边界层方面所起的作用，以及它在向北行星际磁场期间向磁尾等离子体片提供等离子体方面的作用。磁流体动力学(MHD)模拟和大规模动力学(LSK)计算将被用来跟踪从太阳风到等离子体片的场和粒子。将使用现场测量和地面观测来初始化和验证MHD和LSK模拟。虽然调查将主要集中在受冲击的国际货币基金组织与高纬度地区的地磁场重新连接的时期，但也将调查在较低纬度发生的重新连接的情况。根据对ACE、CLUSTER、GEOTAIL、极地和WIND航天器的观测数据以及超级双极光雷达网(SuperDARN)国际高频雷达网的地面数据进行的协调分析，确定了一系列具体的模拟研究，以用于调查。这些研究的主题包括高纬度日侧磁层的大尺度结构和动力学、高纬度区域与磁层其他部分的连通性、高纬度区域的结构和动力学所涉及的大尺度动力学过程以及LLBL的形成和太阳风等离子体向等离子体片的输送。这项调查将对地球空间环境建模计划的全球互动(GI)运动的最终目标做出重大贡献。

This project will investigate the large-scale properties and consequences of magnetic merging processes (reconnection) at the high-latitude dayside magnetopause. It will examine the contribution of high-latitude reconnection to the transport of mass, energy, and momentum from the solar wind to the magnetosphere. In particular, the investigation will focus on determining the role played by magnetic reconnection in the maintenance and the occasional thickening of the low latitude boundary layer (LLBL), as well as its role in providing plasma to the magnetotail plasma sheet during periods of northward interplanetary magnetic field (IMF). Magnetohydrodynamic (MHD) simulations and large-scale kinetic (LSK) calculations will be employed to follow fields and particles from the solar wind to the plasma sheet. Both in-situ measurements and ground observations will be used to initialize and validate the MHD and LSK simulations. Although the investigation will primarily focus on periods in which the shocked IMF reconnects with the geomagnetic field at high latitudes, cases of reconnection occurring at lower latitudes will also be investigated. A series of specific simulation studies based on the coordinated analysis of observations from the ACE, CLUSTER, GEOTAIL, POLAR, and WIND spacecraft, as well as ground-based data from the Super Dual Auroral Radar Network (SuperDARN) international network of high-frequency radars, have been identified for use in the investigation. The subjects of these studies include the large-scale structure and dynamics of the high-latitude dayside magnetosphere, the connectivity of the high-latitude region with the rest of the magnetosphere, and the large-scale kinetic processes involved in the structure and dynamics of the high-latitude region as well as the formation of the LLBL and the transport of solar wind plasma to the plasma sheet. The investigation will represent a significant contribution to the ultimate objective of the Geospace Environment Modeling program's Global Interaction (GI) campaign.