Three-dimensional stability of solitary shear kinetic Alfvén waves in a low-beta plasma

1989 ◽  
Vol 41 (1) ◽  
pp. 171-184 ◽  
Author(s):  
K. P. Das ◽  
L. P. J. Kamp ◽  
F. W. Sluijter
Keyword(s):  
Growth Rate ◽  
Dimensional Stability ◽  
Three Dimensional ◽  
Alfven Waves ◽  
Magnetized Plasma ◽  
Alfvén Waves ◽  
Ion Acoustic Solitons ◽  
The Stability ◽  
External Uniform Magnetic Field ◽  
Kinetic Alfvén Waves

The three-dimensional stability of solitary shear kinetic Alfvén waves in a low-β plasma is investigated by the method of Zakharov & Rubenchik (1974). It is found that there is no instability if the direction of perturbation falls within a certain region of space. The growth rate of the instability for the unstable region is determined. This growth rate is found to decrease with increasing angle between the direction of propagation of the solitary wave and the direction of the external uniform magnetic field. A particular case of the present analysis gives results on the stability of ion-acoustic solitons in a magnetized plasma.

Three-dimensional stability of solitary kinetic Alfvé waves and ion-acoustic waves

1994 ◽  
Vol 51 (1) ◽  
pp. 95-111 ◽  
Author(s):  
G. Ghosh ◽  
K. P. Das
Keyword(s):  
Dimensional Stability ◽  
Acoustic Waves ◽  
Three Dimensional ◽  
Perturbation Expansion ◽  
Alfven Waves ◽  
Alfvén Waves ◽  
Ion Acoustic Waves ◽  
Linear Dispersion ◽  
Ion Acoustic ◽  
Kinetic Alfvén Waves

Starting from a set of equations that lead to a linear dispersion relation coupling kinetic Alfvén waves and ion-acoustic waves, three-dimensional KdV equations are derived for these waves. These equations are then used to investigate the three-dimensional stability of solitary kinetic Alfvén waves and ion-acoustic waves by the small-k perturbation expansion method of Rowlands and Infeld. For kinetic Alfvén waves it is found that there is instability if the direction of the plane-wave perturbation lies inside a cone, and the growth rate of the instability attains a maximum when the direction of the perturbation lies in the plane containing the external magnetic field and the direction of propagation of the solitary wave.

Kinetic Alfvén waves in an inhomogeneous anisotropic magnetoplasma in the presence of an inhomogeneous electric field: particle aspect analysis

2000 ◽  
Vol 63 (4) ◽  
pp. 311-328 ◽  
Author(s):  
A. BARONIA ◽  
M. S. TIWARI
Keyword(s):  
Growth Rate ◽  
Dispersion Relation ◽  
Electric Field ◽  
Alfven Waves ◽  
Alfven Wave ◽  
Larmor Radius ◽  
Alfvén Waves ◽  
Temperature Anisotropy ◽  
Inhomogeneous Electric Field ◽  
Kinetic Alfvén Waves

Kinetic Alfvén waves in the presence of an inhomogeneous electric field applied perpendicular to the ambient magnetic field in an anisotropic, inhomogeneous magnetoplasma are investigated. The particle aspect approach is adopted to investigate the trajectories of charged particles in the electromagnetic field of a kinetic Alfvén wave. Expressions are found for the field-aligned current, the perpendicular current, the dispersion relation and the particle energies. The growth rate of the wave is obtained by an energy- conservation method. It is predicted that plasma density inhomogeneity is the main source of instability, and an enhancement of the growth rate by electric field inhomogeneity and temperature anisotropy is found. The dispersion relation and growth rate involve the finite-Larmor-radius effect, electron inertia and the temperature anisotropy of the magnetoplasma. The applicability of the investigation to the auroral acceleration region is discussed.

scholarly journals Kinetic Alfvén waves in three-dimensional magnetic reconnection

2016 ◽  
Vol 121 (7) ◽  
pp. 6526-6548 ◽  
Author(s):  
Ji Liang ◽  
Yu Lin ◽  
Jay R. Johnson ◽  
Xueyi Wang ◽  
Zheng-Xiong Wang
Keyword(s):  
Magnetic Reconnection ◽  
Three Dimensional ◽  
Alfven Waves ◽  
Alfvén Waves ◽  
Kinetic Alfvén Waves

The growth of Alfvén waves in the resistive current-driven instability

1997 ◽  
Vol 58 (3) ◽  
pp. 433-440 ◽  
Author(s):  
GUANG-LI HUANG ◽  
REN-YING WANG
Keyword(s):  
Growth Rate ◽  
Electric Current ◽  
Alfven Waves ◽  
Magnetized Plasma ◽  
Alfvén Waves ◽  
Tearing Mode ◽  
Stability Calculation ◽  
Electrons And Ions ◽  
Linear Friction ◽  
Two Fluid

On the basis of a two-fluid, cold-plasma, linear stability calculation with linear friction between electrons and ions, the growth rate of Alfvén waves is derived from the dispersion relation for a uniformly magnetized plasma, in which the plasma resistivity and a uniform electric current carried by an electron beam are both considered. The growth rate is directly proportional to the plasma resistivity, the electric current density and the value of the parameter ωxpe/Ωe (where ωxpe and Ωe are the electron plasma and cyclotron frequency respectively). Moreover, the growth of Alfvén waves is mainly excited in a direction nearly parallel to the ambient magnetic field. The critical value of the velocity of the electron fluid is just equal to the Alfvén velocity. The results of this paper are compared with those for the linear tearing mode.

Stability of Alfvén wings in uniform plasmas

2007 ◽  
Vol 73 (6) ◽  
pp. 957-966
Author(s):  
P. A. SALLAGO ◽  
A. M. PLATZECK
Keyword(s):  
Solar System ◽  
Normal Modes ◽  
Background Field ◽  
Alfven Waves ◽  
Magnetized Plasma ◽  
Alfvén Waves ◽  
Solar System Bodies ◽  
Uniform Background ◽  
The Stability ◽  
Magnetohydrodynamic System

AbstractA conducting source moving uniformly through a magnetized plasma generates, among a variety of perturbations, Alfvén waves. An interesting characteristic of Alfvén waves is that they can build up structures in the plasma called Alfvén wings. These wings have been detected and measured in many solar system bodies, and their existence has also been theoretically proven. However, their stability remains to be studied. The aim of this paper is to analyze the stability of an Alfvén wing developed in a uniform background field, in the presence of an incompressible perturbation that has the same symmetry as the Alfvén wing, in the magnetohydrodynamic approximation. The study of the stability of a magnetohydrodynamic system is often performed by linearizing the equations and using either the normal modes method or the energy method. In spite of being applicable for many problems, both methods become algebraically complicated if the structure under analysis is a highly non-uniform one. Palumbo has developed an analytical method for the study of the stability of static structures with a symmetry in magnetized plasmas, in the presence of incompressible perturbations with the same symmetry as the structure (Palumbo 1998 Thesis, Universidad de Firenze, Italia). In the present paper we extend this method for Alfvén wings that are stationary structures, and conclude that in the presence of this kind of perturbation they are stable.

Parametric excitation of upper hybrid and kinetic alfven waves in a magnetized plasma

1998 ◽  
Vol 4 (1) ◽  
pp. 108-112 ◽  
Author(s):  
A.K. Yukhimuk ◽  
◽  
V.N. Fedun ◽  
V.A. Yukhimuk ◽  
V.N. Ivchenko ◽  
...  
Keyword(s):  
Parametric Excitation ◽  
Alfven Waves ◽  
Magnetized Plasma ◽  
Alfvén Waves ◽  
Kinetic Alfvén Waves

scholarly journals On the stability of solitary kinetic Alfvén waves

1979 ◽  
Vol 73 (5-6) ◽  
pp. 389-390 ◽  
Author(s):  
J.P. Sheerin ◽  
R.S.B. Ong
Keyword(s):  
Alfven Waves ◽  
Alfvén Waves ◽  
The Stability ◽  
Kinetic Alfvén Waves

Effect of the general loss-cone distribution function on kinetic Alfvén waves—a kinetic approach

2007 ◽  
Vol 73 (6) ◽  
pp. 911-920 ◽  
Author(s):  
NIDHI SHUKLA ◽  
P. VARMA ◽  
M.S. TIWARI
Keyword(s):  
Growth Rate ◽  
Distribution Function ◽  
Alfven Waves ◽  
Wave Frequency ◽  
Kinetic Approach ◽  
Wave Number ◽  
Alfvén Waves ◽  
Ion Temperature ◽  
Loss Cone ◽  
Kinetic Alfvén Waves

AbstractKinetic Alfvén waves are investigated in the presence of a general loss-cone distribution function including finite electron pressure and ion-gyroradius effects. The dispersion relation and damping/growth rate are evaluated for different electron to ion temperature ratios, Te/Ti, using a kinetic approach. The wave frequency ω and damping/growth rate γL are evaluated for two regimes of propagation, k⊥ρi < 1 and k⊥ρi > 1, where k⊥ is the perpendicular wave number and ρi is the ion-gyroradius. An enhancement of the wave frequency and a reduction in the damping rate are predicted by steep loss-cone distribution indices and Te/Ti. The growth of the wave is also noticed at higher values of the distribution index and lower Te/Ti. Plasma parameters appropriate to the plasma sheet boundary layer (PSBL) are used to discuss the propagation of kinetic Alfvén waves from the PSBL to the auroral ionosphere.

scholarly journals The inherently three-dimensional nature of magnetized plasma turbulence

2014 ◽  
Vol 81 (2) ◽  
Author(s):  
Gregory G. Howes
Keyword(s):  
Three Dimensional ◽  
Turbulent Energy ◽  
Plasma Turbulence ◽  
Alfven Waves ◽  
Magnetized Plasma ◽  
Alfvén Waves ◽  
Mathematical Form ◽  
Two Dimensional ◽  
Nonlinear Properties ◽  
Azimuthal Asymmetries

It is often asserted or implicitly assumed, without justification, that the results of two-dimensional investigations of plasma turbulence are applicable to the three-dimensional plasma environments of interest. A projection method is applied to derive two scalar equations that govern the nonlinear evolution of the Alfvénic and pseudo-Alfvénic components of ideal incompressible magnetohydrodynamic (MHD) plasma turbulence. The mathematical form of these equations makes clear the inherently three-dimensional nature of plasma turbulence, enabling an analysis of the nonlinear properties of two-dimensional limits often used to study plasma turbulence. In the anisotropic limit, k⊥ ≫ k∥, that naturally arises in magnetized plasma systems, the perpendicular 2D limit retains the dominant nonlinearities that are mediated only by the Alfvénic fluctuations but lacks the wave physics associated with the linear term that is necessary to capture the anisotropic cascade of turbulent energy. In the in-plane 2D limit, the nonlinear energy transfer is controlled instead by the pseudo-Alfvén waves, with the Alfvén waves relegated to a passive role. In the oblique 2D limit, an unavoidable azimuthal dependence connecting the wavevector components will likely cause artificial azimuthal asymmetries in the resulting turbulent dynamics. Therefore, none of these 2D limits is sufficient to capture fully the rich three-dimensional nonlinear dynamics critical to the evolution of plasma turbulence.

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