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

University Of New Hampshire, Durham NH

Investigators

Abstract

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