Linear theory for fast collisionless magnetic reconnection in the lower-hybrid frequency range

Journal Article · Sun May 15 04:00:00 EDT 2005 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.1900094· OSTI ID:20722046

Jovanovic, D; Shukla, P K ^[1]

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1. Institute of Physics, P.O. Box 57, 11001 Belgrade (Serbia and Montenegro)

A linear theory is presented for the interplay between the fast collisionless magnetic reconnection and the lower-hybrid waves that has been observed in recent computer simulations [J. F. Drake, M. Swisdak, C. Cattell et al., Science 299, 873 (2003)]. In plasma configurations with a strong guide field and anisotropic electron temperature, the electron dynamics is described within the framework of standard electron magnetohydrodynamic equations, accounting also for the effects of the electron polarization and ion motions in the presence of perpendicular electric fields. In the linear phase, we find two types of instabilities of a thin current sheet with steep edges, corresponding to its filamentation (or tearing) and bending. Using a surface-wave formalism for the perturbations whose wavelength is larger than the thickness of the current sheet, the corresponding growth rates are calculated as the contributions of singularities in the plasma dispersion function. These are governed by the electron inertia and the linear coupling of the reconnecting magnetic field with local plasma modes propagating in the perpendicular direction that are subject to the Buneman instability. The linear surface wave instability may be particularly important as a secondary instability, dissipating the thin current sheets that develop in the course of the fast reconnection in the shear-Alfven and kinetic-Alfven regimes, and providing the anomalous resistivity for the growth of magnetic islands beyond the shear-Alfven and kinetic-Alfven scales.

• OSTI ID: 20722046
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 5 Vol. 12; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ALFVEN WAVES
MAGNETIC ISLANDS
MAGNETIC RECONNECTION
MAGNETOHYDRODYNAMICS
PLASMA
PLASMA SURFACE WAVES
TEARING INSTABILITY