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Title: Suppression of collisionless magnetic reconnection in asymmetric current sheets

Abstract

Using fully kinetic simulations, we study the suppression of asymmetric reconnection in the limit where the diamagnetic drift speed ≫ Alfvén speed and the magnetic shear angle is moderate. We demonstrate that the slippage between electrons and the magnetic flux mitigates the suppression and can even result in fast reconnection that lacks one of the outflow jets. Through comparing a case where the diamagnetic drift is supported by the temperature gradient with a companion case that has a density gradient instead, we identify a robust suppression mechanism. The drift of the x-line is slowed down locally by the asymmetric nature of the x-line, and then the x-line is run over and swallowed by the faster-moving following flux.

Authors:
;  [1]
  1. NASA-Goddard Space Flight Center, Greenbelt, Maryland 20771 (United States)
Publication Date:
OSTI Identifier:
22598929
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 23; Journal Issue: 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ASYMMETRY; COMPARATIVE EVALUATIONS; DENSITY; ELECTRONS; INHIBITION; MAGNETIC FLUX; MAGNETIC RECONNECTION; SHEAR; SHEETS; SIMULATION; TEMPERATURE GRADIENTS; VELOCITY

Citation Formats

Liu, Yi-Hsin, and Hesse, Michael. Suppression of collisionless magnetic reconnection in asymmetric current sheets. United States: N. p., 2016. Web. doi:10.1063/1.4954818.
Liu, Yi-Hsin, & Hesse, Michael. Suppression of collisionless magnetic reconnection in asymmetric current sheets. United States. doi:10.1063/1.4954818.
Liu, Yi-Hsin, and Hesse, Michael. 2016. "Suppression of collisionless magnetic reconnection in asymmetric current sheets". United States. doi:10.1063/1.4954818.
@article{osti_22598929,
title = {Suppression of collisionless magnetic reconnection in asymmetric current sheets},
author = {Liu, Yi-Hsin and Hesse, Michael},
abstractNote = {Using fully kinetic simulations, we study the suppression of asymmetric reconnection in the limit where the diamagnetic drift speed ≫ Alfvén speed and the magnetic shear angle is moderate. We demonstrate that the slippage between electrons and the magnetic flux mitigates the suppression and can even result in fast reconnection that lacks one of the outflow jets. Through comparing a case where the diamagnetic drift is supported by the temperature gradient with a companion case that has a density gradient instead, we identify a robust suppression mechanism. The drift of the x-line is slowed down locally by the asymmetric nature of the x-line, and then the x-line is run over and swallowed by the faster-moving following flux.},
doi = {10.1063/1.4954818},
journal = {Physics of Plasmas},
number = 6,
volume = 23,
place = {United States},
year = 2016,
month = 6
}
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