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Title: Dissipation in magnetic reconnection with a guide magnetic field

Abstract

A combination of numerical simulation results and analytical theory is applied to the problem of magnetic reconnection in a guide magnetic field. An investigation of electron distribution functions within the electron diffusion region leads to a picture of mixing of particles with different acceleration histories on electron Larmor scales. Based on an apparent average loss of accelerated particles by field-aligned and ExB transport, it is proposed that the role of the reconnection electric field is to replenish this loss by acceleration of particles that enter the electron diffusion region. Analytic theory is employed to verify this model, and an equation is derived, which balances the average electric field force density by a diffusion term applied to the electron momentum density. The diffusion coefficient contains explicitly the electron Larmor spatial scale and a poloidal transport time scale.

Authors:
 [1]
  1. NASA Goddard Space Flight Center, Greenbelt, Maryland 20771 (United States)
Publication Date:
OSTI Identifier:
20860424
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 13; Journal Issue: 12; Other Information: DOI: 10.1063/1.2403784; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ACCELERATION; COMPUTERIZED SIMULATION; DIFFUSION; DISTRIBUTION FUNCTIONS; ELECTRIC FIELDS; ELECTROMAGNETIC FIELDS; ELECTRONS; MAGNETIC FIELDS; MAGNETIC RECONNECTION; MAGNETOHYDRODYNAMICS; NUMERICAL ANALYSIS; PLASMA; PLASMA DENSITY; PLASMA SIMULATION; RADIATION TRANSPORT

Citation Formats

Hesse, Michael. Dissipation in magnetic reconnection with a guide magnetic field. United States: N. p., 2006. Web. doi:10.1063/1.2403784.
Hesse, Michael. Dissipation in magnetic reconnection with a guide magnetic field. United States. doi:10.1063/1.2403784.
Hesse, Michael. Fri . "Dissipation in magnetic reconnection with a guide magnetic field". United States. doi:10.1063/1.2403784.
@article{osti_20860424,
title = {Dissipation in magnetic reconnection with a guide magnetic field},
author = {Hesse, Michael},
abstractNote = {A combination of numerical simulation results and analytical theory is applied to the problem of magnetic reconnection in a guide magnetic field. An investigation of electron distribution functions within the electron diffusion region leads to a picture of mixing of particles with different acceleration histories on electron Larmor scales. Based on an apparent average loss of accelerated particles by field-aligned and ExB transport, it is proposed that the role of the reconnection electric field is to replenish this loss by acceleration of particles that enter the electron diffusion region. Analytic theory is employed to verify this model, and an equation is derived, which balances the average electric field force density by a diffusion term applied to the electron momentum density. The diffusion coefficient contains explicitly the electron Larmor spatial scale and a poloidal transport time scale.},
doi = {10.1063/1.2403784},
journal = {Physics of Plasmas},
number = 12,
volume = 13,
place = {United States},
year = {Fri Dec 15 00:00:00 EST 2006},
month = {Fri Dec 15 00:00:00 EST 2006}
}
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