CAREER: Collisionless Magnetic Reconnection in the Earth's Magnetosphere

等离子体中的磁重联无处不在，发生在实验室等离子体设备、地球磁层、日光层、太阳和天体物理等离子体中。该项目将主要致力于了解地球磁层中的磁场重联，但对这一过程的基本物理理解将对等离子体研究的许多领域产生影响。这个项目解决的主要问题是：(1)磁重联总是突发性的和时间相关的吗？是否存在长时间保持稳定的磁重联的情况？(2)磁重联如何给地球磁层中的粒子提供能量？与岛屿收缩相关的费米过程是否发挥了关键作用？这个费米过程的特征是什么？在什么磁层参数下它是活跃的？(3)在更真实的几何形状中适用于磁层重联的重联的特征和性质是什么？磁层叶密度极低和日侧磁层顶的不对称流入条件如何影响重联信号和重联速率？围绕日侧磁层中的3D磁零点和隔离线的内在3D重联的本质是什么？霍尔物理学是否从根本上改变了这种3D重联的性质？这些问题将通过广泛的数值模拟来研究，使用双流体、混合和全粒子模拟，并实施新的边界条件，如开放边界。该项目还将测试一种名为“无方程投影积分”(EFPI)的新的多尺度模拟技术的有效性，该技术有可能对磁重联研究产生革命性的影响，允许进行仍包括重要动力学物理的超大规模模拟。教育计划是该项目的重要组成部分，其重点是吸引和留住学生进入空间物理领域。为了提高学生的兴趣，有面向高中生和本科生的外展计划，在本科生和研究生层面开设新的空间物理课程，并通过一个统一的网站更好地宣传特拉华大学(UDELL)的空间物理计划。为了增加学生的兴趣和留存，教育和研究活动相结合，将高中、本科生和研究生纳入研究计划。每周一次的小组会议和导师培训将被用来创建一个“导师脚手架”，在这个脚手架上，年纪大的学生帮助培训和指导年轻的学生。将通过向少数族裔学生提供暑期高中研究体验来促进代表不足群体的参与。最后，将通过收集关于参加Udel空间物理计划的学生的教育和职业选择的统计数据来评估教育活动的影响。

Magnetic reconnection in plasmas is ubiquitous and occurs in laboratory plasma devices, in Earth's magnetosphere, in the heliosphere, on the sun and in astrophysical plasmas. This project will be primarily oriented toward understanding magnetic reconnection in Earth's magnetosphere, but the fundamental, physical understanding of the process will have impacts on many areas of plasma research. The primary questions addressed by this project are: (1) Is magnetic reconnection always bursty and time dependent? Are there situations in which magnetic reconnection can be steady for long periods of time? (2) How does magnetic reconnection energize particles in the Earth's magnetosphere? Does a Fermi process associated with contracting islands play a critical role? What are the signatures expected from this Fermi process, and under what magnetospheric parameters is it active? (3) what are the signatures and properties of reconnection in more realistic geometries applicable to magnetospheric reconnection? How are the signatures and rate of reconnection affected by extremely low density in the magnetospheric lobes and asymmetric inflow conditions at the dayside magnetopause? What is the nature of inherently 3D reconnection around 3D magnetic nulls and separator lines in the dayside magnetosphere? Does Hall physics fundamentally modify the nature of this 3D reconnection? These questions will be studied with a broad range of numerical simulations, using two-fluid, hybrid, and full particle simulations, and implementing new boundary conditions such as open boundaries. The project will also test the effectiveness of a novel multiscale simulation technique called, "Equation Free Projective Integration" (EFPI) which has the potential to have a transformative effect on magnetic reconnection studies, allowing extremely large scale simulations which still include important kinetic physics. The education plan that forms an important part of the project is focused on attracting and retaining students into the field of space physics. To increase student interest, there are outreach programs to high school students and undergraduates, new space physics courses at the undergraduate and graduate level, and better visibility of the University of Delaware (UDEL) space physics program through a unified web site. In order to increase student interest and retention, education and research activities are integrated by including high school, undergraduate, and graduate students in the research program. Weekly group meetings and mentor training will be used to create a "scaffolding of mentoring," whereby older students help to train and mentor younger ones. The participation of underrepresented groups will be promoted by providing the summer high school research experience to a minority student. Finally, the impact of the educational activities will be evaluated by collecting statistics on the education and career choices of students who participate in the UDEL space physics program.