Vortices at the magnetic equator generated by hybrid Alfvén resonant waves
Abstract
We performed threedimensional magnetohydrodynamic simulations of shear Alfvén waves in a full field line system with magnetosphereionosphere coupling and plasma nonuniformities. Feedback instability of the Alfvén resonant modes showed various nonlinear features under the field line cavities: (i) a secondary flow shear instability occurs at the magnetic equator, (ii) trapping of the ionospheric Alfvén resonant modes facilitates deformation of fieldaligned current structures, and (iii) hybrid Alfvén resonant modes grow to cause vortices and magnetic oscillations around the magnetic equator. Essential features in the initial brightening of auroral arc at substorm onsets could be explained by the dynamics of Alfvén resonant modes, which are the nature of the field line system responding to a background rapid change.
 Authors:
 National Institute of Polar Research, Midoricho 103, Tachikawa, Tokyo 1908518 (Japan)
 Publication Date:
 OSTI Identifier:
 22408009
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 1; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ALFVEN WAVES; COMPUTERIZED SIMULATION; DEFORMATION; EARTH MAGNETOSPHERE; EQUATOR; IONOSPHERE; MAGNETIC FIELDS; MAGNETOHYDRODYNAMICS; NONLINEAR PROBLEMS; OSCILLATIONS; PLASMA; RESONANCE; SHEAR; THREEDIMENSIONAL CALCULATIONS; VORTICES
Citation Formats
Hiraki, Yasutaka, Email: hiraki.yasutaka@nipr.ac.jp. Vortices at the magnetic equator generated by hybrid Alfvén resonant waves. United States: N. p., 2015.
Web. doi:10.1063/1.4905642.
Hiraki, Yasutaka, Email: hiraki.yasutaka@nipr.ac.jp. Vortices at the magnetic equator generated by hybrid Alfvén resonant waves. United States. doi:10.1063/1.4905642.
Hiraki, Yasutaka, Email: hiraki.yasutaka@nipr.ac.jp. 2015.
"Vortices at the magnetic equator generated by hybrid Alfvén resonant waves". United States.
doi:10.1063/1.4905642.
@article{osti_22408009,
title = {Vortices at the magnetic equator generated by hybrid Alfvén resonant waves},
author = {Hiraki, Yasutaka, Email: hiraki.yasutaka@nipr.ac.jp},
abstractNote = {We performed threedimensional magnetohydrodynamic simulations of shear Alfvén waves in a full field line system with magnetosphereionosphere coupling and plasma nonuniformities. Feedback instability of the Alfvén resonant modes showed various nonlinear features under the field line cavities: (i) a secondary flow shear instability occurs at the magnetic equator, (ii) trapping of the ionospheric Alfvén resonant modes facilitates deformation of fieldaligned current structures, and (iii) hybrid Alfvén resonant modes grow to cause vortices and magnetic oscillations around the magnetic equator. Essential features in the initial brightening of auroral arc at substorm onsets could be explained by the dynamics of Alfvén resonant modes, which are the nature of the field line system responding to a background rapid change.},
doi = {10.1063/1.4905642},
journal = {Physics of Plasmas},
number = 1,
volume = 22,
place = {United States},
year = 2015,
month = 1
}

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