Magnetospheric Current Sheets and Boundary Layers

磁层电流片和边界层

• 批准号: 9113664
• 负责人: Bengt Sonnerup
• 金额: $ 40.06万
• 依托单位: Dartmouth College
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-01-01 至 1995-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9113664&HistoricalAwards=false
• 关键词: Magnetospheric; Current; Sheets; Boundary; Layers

This ongoing research program is concerned with some of the physical processes and structures that occur in thin electrical current sheets and plasma boundary layers in the Earth's magnetosphere, with special emphasis on the magnetopause. This current sheet forms the outer boundary of the magnetosphere and separates it from the rapidly streaming solar wind. The proposed research is centered in three areas. The first of these is concerned with the development and testing of data-analysis methods for single-spacecraft data that can be used to examine the two-dimensional or three-dimensional structure of the magnetopause itself as well as the geometry of bulges, or deformations of the magnetopause, caused by magnetic flux connection across the current layer (so-called FTEs) or by dynamic-pressure pulses in the solar wind. The data to be used in this part of the study were obtained by the AMPTE/IRM spacecraft. The second area concerns the development of analytic and numerical models of one-dimensional current sheets representing so-called intermediate shocks which are dissipative and rotational discontinuities, which are nondissipative. Both of these types of magnetic and plasma structures have been proposed to represent the magnetopause during periods of magnetic field reconnection. The third area of study is the reconnection process itself and the manner in which it may be initiated and grow in the region near the subsolar magnetopause. Analytical theory, as well as numerical simulation methods will be employed.

这项正在进行的研究计划涉及地球磁层中薄电流片和等离子体边界层中发生的一些物理过程和结构，特别强调磁层顶。 该电流片形成了磁层的外边界，并将其与快速流动的太阳风分开。 拟议的研究集中在三个领域。 第一个涉及单航天器数据的数据分析方法的开发和测试，这些方法可用于检查磁层顶本身的二维或三维结构，以及由当前层的磁通量连接（所谓的 FTE）或太阳风中的动态压力脉冲引起的凸起的几何形状或磁层顶的变形。 这部分研究中使用的数据是由 AMPTE/IRM 航天器获得的。 第二个领域涉及代表所谓中间激波的一维电流片的分析和数值模型的开发，中间激波是耗散和旋转不连续性的，它们是非耗散的。 这两种类型的磁性和等离子体结构都被提议用来代表磁场重联期间的磁层顶。 研究的第三个领域是重联过程本身以及重联过程在太阳下磁层顶附近区域启动和生长的方式。 将采用分析理论以及数值模拟方法。