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

磁场重联是一种重要的能量转换过程，它可以脉冲释放储存的磁能，与太阳、磁层和实验室等离子体密切相关。在无碰撞重联扩散区的粒子特性及其演化是一个很大程度上未知的领域，特别是在3D。这项研究将结合联合收割机数据分析，模拟和工程专业知识，利用多航天器使命集群的数据绘制出磁尾重联离子扩散区域内不同的电子区域。 2D和3D PIC模拟将指导聚类数据的解释。项目时间表：在第一年，将重建磁尾星团重联事件的不同电子区域，并将通过PIC模拟研究重联过程中电子分布函数的演变。在第二年，我们将利用2D PIC模拟和高分辨率的Cluster EDI电子数据，研究重联过程中电子流片内的电子特性和动力学。在第三年，我们将利用Cluster和PIC模拟数据，在3D重联中确定关键能量转换点周围的不同电子区域，包括磁零。该提案旨在了解空间等离子体中的非线性能量转换物理学，该物理学对太阳和天体物理学以及实验室重新连接具有重要应用。这项研究是理解空间重联层消失的关键。预期的新知识将进一步我们的动力学尺度等离子体过程如何耦合到宏观现象，如磁层亚暴的理解。从拟议的调查结果将在AGU会议上传达给科学界，等离子体物理会议的APS分部。作为拟议努力的一部分，结果将发表在参考期刊上。通过拟议项目获得的结果将编入关于磁尾重联的小型课程。微型课程将作为介绍磁层中的一个关键能量转换过程，供大学预科生（通过UNH与哈莱姆儿童协会的伙伴关系）、UNH的本科生和研究生使用。该奖项由数学和物理科学理事会物理司和地球科学理事会大气科学司共同资助

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