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Title: Computer studies on powerful magnetic energy conversion by the spontaneous fast reconnection mechanism

Abstract

On the basis of the spontaneous reconnection model, computer simulations study the physical mechanism by which magnetic energy, initially stored in a current sheet system, is released into plasma energies. For the uniform resistivity model, the Sweet--Parker mechanism is eventually set up with the diffusion region becoming longer with time. It is the Ohmic heating {eta}{bold J}{sup 2} in the diffusion region that plays the dominant role in releasing the magnetic energy. Attached to the diffusion region, a long plasmoid is formed and propagates like a large-amplitude Alfven pulse, where the generator and motor effects are canceled along the plasmoid boundary. For the anomalous resistivity model, the fast reconnection mechanism is eventually set up with the diffusion region remaining to be localized near an X neutral point. It is the powerful motor effect [{bold u}{center_dot}({bold J}{times}{bold B}){gt}0] along the slow shock layers that drastically releases the stored magnetic energy. A large-scale plasmoid distinctly swells, so that the ambient magnetic fields are compressed (by the generator effect), and the enhanced magnetic energy is then reduced by the strong motor effect in the backward half of the plasmoid. The slow shocks extend with time from near the X point, leading to amore » drastic catastrophe for the overall magnetic field system. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.« less

Authors:
 [1]
  1. Department of Computer Science, Faculty of Engineering Ehime University, Matsuyama 790 (Japan)
Publication Date:
OSTI Identifier:
165979
Resource Type:
Journal Article
Journal Name:
Physics of Plasmas
Additional Journal Information:
Journal Volume: 2; Journal Issue: 2; Other Information: PBD: Feb 1995
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION; MAGNETIC RECONNECTION; ENERGY CONVERSION; PLASMOIDS; DIFFUSION; SHOCK WAVES; SOLAR FLARES; EARTH MAGNETOSPHERE; MAGNETOHYDRODYNAMICS; PLASMA SIMULATION; MAGNETIC REYNOLDS NUMBER

Citation Formats

Ugai, M. Computer studies on powerful magnetic energy conversion by the spontaneous fast reconnection mechanism. United States: N. p., 1995. Web. doi:10.1063/1.870965.
Ugai, M. Computer studies on powerful magnetic energy conversion by the spontaneous fast reconnection mechanism. United States. https://doi.org/10.1063/1.870965
Ugai, M. Wed . "Computer studies on powerful magnetic energy conversion by the spontaneous fast reconnection mechanism". United States. https://doi.org/10.1063/1.870965.
@article{osti_165979,
title = {Computer studies on powerful magnetic energy conversion by the spontaneous fast reconnection mechanism},
author = {Ugai, M},
abstractNote = {On the basis of the spontaneous reconnection model, computer simulations study the physical mechanism by which magnetic energy, initially stored in a current sheet system, is released into plasma energies. For the uniform resistivity model, the Sweet--Parker mechanism is eventually set up with the diffusion region becoming longer with time. It is the Ohmic heating {eta}{bold J}{sup 2} in the diffusion region that plays the dominant role in releasing the magnetic energy. Attached to the diffusion region, a long plasmoid is formed and propagates like a large-amplitude Alfven pulse, where the generator and motor effects are canceled along the plasmoid boundary. For the anomalous resistivity model, the fast reconnection mechanism is eventually set up with the diffusion region remaining to be localized near an X neutral point. It is the powerful motor effect [{bold u}{center_dot}({bold J}{times}{bold B}){gt}0] along the slow shock layers that drastically releases the stored magnetic energy. A large-scale plasmoid distinctly swells, so that the ambient magnetic fields are compressed (by the generator effect), and the enhanced magnetic energy is then reduced by the strong motor effect in the backward half of the plasmoid. The slow shocks extend with time from near the X point, leading to a drastic catastrophe for the overall magnetic field system. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.},
doi = {10.1063/1.870965},
url = {https://www.osti.gov/biblio/165979}, journal = {Physics of Plasmas},
number = 2,
volume = 2,
place = {United States},
year = {1995},
month = {2}
}