Solar Wind - Magnetosphere - Ionosphere Coupling

太阳风-磁层-电离层耦合

• 批准号: 9503423
• 负责人: George Siscoe
• 金额: --
• 依托单位: Trustees of Boston University
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-07-15 至 1999-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9503423&HistoricalAwards=false
• 关键词: Solar; Wind; Magnetosphere; Ionosphere; Coupling

The proposed research program is directed at determining the global geometry of the open magnetosphere and its connection to the ionosphere. The program will build on much of the proposing team's prior work as well as related work of others. Four programmatic elements are: 1. analyses of IMP 8 plasma and field data to specify and document the open geometry of the tail; 2. comparisons of these results with global MHD simulations to test simulation applicability and to extend the description of the open geometry to the full magnetosphere; 3. comparisons of both observational and simulation results with appropriately constructed, multi-component superposition models to elucidate the magnetic topology of the open geometry at higher resolution than obtainable with the MHD model; and 4. extend the LLBL-ionosphere coupling model of Siscoe, Lotko, Sonnerup, and Maynard to incorporate the new geometry. A focusing objective for the stated program, to determine the global open geometry of the magnetosphere, is to ascertain explicitly the 3- dimensional geometry of the topological separatrices of the magnetic field, of which there might be several sets of distinct topological types. This will be done for various orientations of the interplanetary magnetic field (IMF), including northward, which perhaps poses the greatest challenge. Locating these topological features relative to the geometry of the main structural elements of the magnetosphere will bear directly on answers to the following questions: Where are the sites of magnetic reconnection at the magnetopause and in the tail? How do they fit within the global geometry? What is the geometrical distribution of the open and closed regions on the 3-D magnetospheric boundary: The answer to this last question bears directly on the question of the spatial relationships between the dayside cusp, the low-latitude boundary layer (LLBL), and the plasma mantle, and on the question of whether the LLBL is open or closed.

拟议的研究方案旨在确定开放磁层的全球几何形状及其与电离层的联系。该计划将建立在大部分建议团队的先前工作以及其他人的相关工作。四个方案要素是：1。分析IMP 8等离子体和场数据，以指定和记录尾部的开放几何形状; 2.将这些结果与全球MHD模拟进行比较，以测试模拟的适用性，并将开放几何的描述扩展到整个磁层; 3.将观测和模拟结果与适当构造的多分量叠加模型进行比较，以比MHD模型更高的分辨率阐明开放几何的磁拓扑结构;以及4.扩展Siscoe，Lotko，Sonnerup和Maynard的LLBL-电离层耦合模型，以纳入新的几何形状。所述方案的一个重点目标是确定磁层的全球开放几何，明确地确定磁场的拓扑分界线的三维几何，其中可能有几组不同的拓扑类型。这将针对行星际磁场（IMF）的各种方向进行，包括可能构成最大挑战的北向。定位这些相对于磁层的主要结构元素的几何拓扑特征将直接影响到以下问题的答案：磁重联在磁层顶和尾部的网站在哪里？它们如何适应全球几何？3-D磁层边界上开放和封闭区域的几何分布是什么：最后一个问题的答案直接关系到向阳面尖点、低纬边界层（LLBL）和等离子体地幔之间的空间关系，以及LLBL是开放还是封闭的问题。