Distinct Electron Regions in 2D and 3D Collisionless Magnetic Reconnection

磁重联是一种重要的能量转换过程，可以脉冲释放储存的磁能，与太阳、磁层和实验室等离子体高度相关。粒子特性及其在无碰撞重连接扩散区的演化是一个很大程度上未知的领域，特别是在三维中。这项研究将结合数据分析、模拟和工程专业知识，利用多航天器任务Cluster的数据，在磁尾重联的离子扩散区域绘制出不同的电子区域，2D和3D PIC模拟将指导对Cluster数据的解释。项目进度：第一年将重建磁尾中簇重联事件的不同电子区域，并通过PIC模拟研究重联过程中电子分布函数的演变。在第二年，将使用2D PIC模拟和高分辨率簇EDI电子数据在重新连接过程中研究电子特性和动力学。在第三年，将在使用Cluster和PIC模拟数据的3D重联中确定关键能量转换位点周围的不同电子区域，包括磁null。该提案旨在理解空间等离子体中的非线性能量转换物理，该物理在太阳和天体物理以及实验室重连接中具有重要应用。所提出的研究是理解空间中重连层的耗散的关键。预期的新知识将进一步加深我们对动力学尺度等离子体过程如何与宏观现象（如磁层亚暴）耦合的理解。拟议调查的结果将在AGU会议和APS等离子体物理部门会议上传达给科学界。作为提议工作的一部分，研究结果将发表在评审期刊上。通过提出的项目获得的结果将被组织成一个关于磁尾重联的迷你课程。这门迷你课程将为大学预科学生（通过与哈莱姆儿童协会的合作）、大学本科生和研究生介绍磁层中关键的能量转换过程。该提案已提交给NSF-DoE等离子体科学与工程合作项目联合招标08-589。该奖项由数学和物理科学理事会物理部和地球科学理事会大气科学部联合资助

Magnetic reconnection is an important energy conversion process that can impulsively release stored magnetic energies, and is highly relevant to solar, magnetospheric, and laboratory plasmas. Particle characteristics and their evolution in the diffusion region of collisionless reconnection is a largely unknown area, especially in 3D. This research will combine data analysis, simulation, and engineering expertise to map out distinct electron regions within the ion diffusion region of magnetotail reconnection using data from the multi-spacecraft mission Cluster. 2D and 3D PIC simulations will guide the interpretation of Cluster data. The project schedule:In year 1, distinct electron regions for Cluster reconnection events in the magnetotail will be reconstructed and the evolution of electron distribution functions during the course of reconnection will be investigated by PIC simulations. In year 2, electron characteristics and dynamics will be studied within the evolving electron current sheet during reconnection using 2D PIC simulations and high-resolution Cluster EDI electron data.In year 3, distinct electron regions around key energy conversion sites will be identified, including magnetic nulls, in 3D reconnection using Cluster and PIC simulation data. This proposal seeks to understand the nonlinear energy conversion physics in space plasmas that has crucial applications to solar and astrophysical physics as well as laboratory reconnection. The proposed study is key to understanding dissapation in reconnection layers in space. The expected new knowledge will further our understanding of how kinetic-scale plasma processes couple to macroscopic phenomena such as magnetospheric substorms.Results from the proposed investigation will be communicated to the science community in AGU meetings, and APS Division of Plasma Physics meetings. As part of the proposed effort, the results will be published in refereed journals. The results obtained through the proposed project will be organized into a minicourse on reconnection in the magnetotail. The minicourse will serve as an introduction to a key energy conversion process in the magnetosphere for pre-college (through partnership of UNH with the Harlem Children Society), undergraduate and graduate students at UNH.This proposal was submitted to the NSF-DoE Partnership in Plasma Science and Engineering joint solicitation 08-589. This award is being funded jointly by the Division of Physics of the Mathematical and Physical Sciences Directorate and by Atmospheric Sciences Division of the Geosciences Directorate