Alfvén wave propagation and dissipation   in a 3D-structured 
 compressible plasma

Abstract. Recent observations from the THEMIS mission have focused attention on the timing of events in the magnetotail during magnetospheric substorms and other periods of geomagnetic activity. Standard models of substorms have generally emphasized convective flows as the major source of energy and momentum transport; however, Alfvén wave propagation can also be an important transport mechanism. The propagation of Alfvén waves and the related field-aligned currents are studied by means of ideal MHD simulation of the tail. Perturbations of the cross-tail current can lead to the generation of such waves, and the resulting propagation both through the tail and along the plasma sheet boundary layer can lead to enhanced transport. Implications of this wave propagation on the interpretation of results from the THEMIS mission will be discussed.

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Frequency-dependent Alfvén-wave Propagation in the Solar Wind: Onset and Suppression of Parametric Decay Instability

The Astrophysical Journal ◽

10.3847/1538-4357/aac218 ◽

2018 ◽

Vol 860 (1) ◽

pp. 17 ◽

Cited By ~ 15

Author(s):

Munehito Shoda ◽

Takaaki Yokoyama ◽

Takeru K. Suzuki

Keyword(s):

Solar Wind ◽

Wave Propagation ◽

Alfven Wave ◽

Frequency Dependent ◽

Decay Instability ◽

Parametric Decay ◽

Parametric Decay Instability

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Fast Alfven wave propagation in a deuterium-hydrogen Tokamak plasma

Plasma Physics and Controlled Fusion ◽

10.1088/0741-3335/29/1/008 ◽

1987 ◽

Vol 29 (1) ◽

pp. 93-103 ◽

Cited By ~ 6

Author(s):

H Akiyama ◽

K L Wong ◽

J Gahl ◽

M Kristiansen ◽

M Hagler

Keyword(s):

Wave Propagation ◽

Alfven Wave ◽

Tokamak Plasma

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Effect of double layers on magnetosphere–ionosphere coupling

Laser and Particle Beams ◽

10.1017/s0263034600002822 ◽

1987 ◽

Vol 5 (2) ◽

pp. 351-366 ◽

Cited By ~ 31

Author(s):

Robert L. Lysak ◽

Mary K. Hudson

Keyword(s):

Wave Propagation ◽

Electric Field ◽

Double Layer ◽

Large Scale ◽

Debye Length ◽

Plasma Temperature ◽

Auroral Zone ◽

Alfven Wave ◽

Scale Model ◽

Double Layers

The earth's auroral zone contains dynamic processes occurring on scales from the length of an auroral zone field line (about 10RE) which characterizes Alfven wave propagation to the scale of microscopic processes which occur over a few Debye lengths (less than 1 km). These processes interact in a time-dependent fashion since the current carried by the Alfven waves can excite microscopic turbulence which can in turn provide dissipation of the Alfven wave energy. This review will first describe the dynamic aspects of auroral current structures with emphasis on consequences for models of microscopic turbulence. In the second part of the paper a number of models of microscopic turbulence will be introduced into a large scale model of Alfven wave propagation to determine the effect of various models on the overall structure of auroral currents. In particular, we will compare the effect of a double layer electric field which scales with the plasma temperature and Debye length with the effect of anomalous resistivity due to electrostatic ion cyclotron turbulence in which the electric field scales with the magnetic field strength. It is found that the double layer model is less diffusive than the resistive model leading to the possibility of narrow, intense current structures.

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