Asymmetry and thermal effects due to parallel motion of electrons in collisionless magnetic reconnection

Journal Article · Fri Nov 01 04:00:00 EST 1996 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.871573· OSTI ID:388939

Tanaka, M ^[1]

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1. Research Laboratory of Electronics and Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

Fast collisionless reconnection of magnetic flux loops by the macro-particle simulation code shows significant asymmetry of the plasma flow under an ambient toroidal magnetic field. The parallel motion of electrons induced by the reconnection electric field is found to produce large density and toroidal magnetic field inhomogeneities of a quadrupole shape, {delta}{ital n}/{ital n}{sub 0}{approximately}0.3, unlike the {ital m}=1 mode. The divergence of the plasma flow is locally not identical to zero with each species, {bold {nabla}}{bold {center_dot}}{ital V}{sup ({ital s})}{ne}0 ({ital s}={ital e},{ital i}), due to the electron spatial movement along the magnetic field. This internal structure results in a thick current layer and enhances the reconnection process. A plasmoid that impedes magnetic reconnection is created when the parallel mass diffusivity of electrons arising from their thermal motion is suppressed (the fluid limit). The reconnection rate becomes a smoothly increasing function of the ion mass and an inverse of the toroidal magnetic field, the latter of which being due to the compressional effect. The rate is drastically reduced when the ion Larmor radius far exceeds the ion skin depth. {copyright} {ital 1996 American Institute of Physics.}

• OSTI ID: 388939
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 11 Vol. 3; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
COLLISIONLESS PLASMA
COMPUTERIZED SIMULATION
EARTH MAGNETOSPHERE
LARMOR RADIUS
MAGNETIC FLUX
MAGNETIC RECONNECTION
PLASMA SIMULATION
PLASMOIDS