Ion- and electron-acoustic waves in sheet plasmas

1989 ◽  
Vol 41 (2) ◽  
pp. 281-287
Author(s):  
M. B. Chaudhry ◽  
M. D. Tahir
Keyword(s):  
Acoustic Waves ◽  
Cyclotron Frequency ◽  
Larmor Radius ◽  
Frequency Range ◽  
Ion Temperature ◽  
Temperature Ratio ◽  
Ion Acoustic Waves ◽  
Poisson Equations ◽  
Electron Acoustic Waves ◽  
Electron Acoustic

Ion-acoustic waves in sheet plasmas, which are of thickness of order of the ion Larmor radius ρi, have been investigated numerically. The frequency range considered is less than the ion cyclotron frequency ωci. An integral equation in wavenumber space is derived from the linearized Vlasov-Poisson equations and analysed numerically. Eigenfrequencies and eigenfunctions of the wave have been studied systematically by varying the plasma thickness, plasma density, electron-to-ion temperature ratio and parallel wavenumber. Electron-acoustic waves are found when the parallel wavenumber is very small (e.g. k∥ρi = 0·005) and the electron and ion temperatures are comparable.

scholarly journals Dromion solutions for nonlinear electron acoustic waves in space plasmas

2002 ◽  
Vol 9 (5/6) ◽  
pp. 463-475 ◽  
Author(s):  
S. S. Ghosh ◽  
A. Sen ◽  
G. S. Lakhina
Keyword(s):  
Acoustic Waves ◽  
Nonlinear Evolution ◽  
Two Dimensions ◽  
Space Plasmas ◽  
Ion Temperature ◽  
Polar Cap ◽  
Localized Solutions ◽  
Electron Acoustic Waves ◽  
Electron Acoustic

Abstract. Recent high resolution measurements of POLAR and FAST satellites have revealed two-dimensional coherent structures in the polar cap boundary layer (PCBL) region. Since the ion temperature is often observed to be greater than the electron temperature in this region, electron acoustic waves can exist as a normal mode of the plasma system. It is shown that the nonlinear evolution of such waves can be modelled by the coupled Davey-Stewartson I equations. These equations, which are a generalization of the nonlinear Schrödinger equation to two dimensions, admit exponentially localized solutions called dromions. A detailed parametric characterization of the regions of existence of such solutions is presented in the context of the PCBL region.

Electron-acoustic solitons in a weakly relativistic plasma

1992 ◽  
Vol 47 (1) ◽  
pp. 61-74 ◽  
Author(s):  
R. L. Mace ◽  
M. A. Hellberg ◽  
R. Bharuthram ◽  
S. Baboolal
Keyword(s):  
Acoustic Waves ◽  
Kdv Equation ◽  
Nonlinear Coefficient ◽  
Soliton Solutions ◽  
Positive Contribution ◽  
Poisson Equations ◽  
Electron Acoustic Waves ◽  
Relativistic Beam ◽  
Component Plasma ◽  
Electron Acoustic

Weakly relativistic electron-acoustic solitons are investigated in a two-electron-component plasma whose cool electrons form a relativistic beam. A general Korteweg-de Vries (KdV) equation is derived, in the small-|ø| domain, for a plasma consisting of an arbitrary number of relativistically streaming fluid components and a hot Boltzmann component. This equation is then applied to the specific case of electron-acoustic waves. In addition, the fully nonlinear system of fluid and Poisson equations is integrated to yield electron-acoustic solitons of arbitrary amplitude. It is shown that relativistic beam effects on electron-acoustic solitons significantly increase the soliton amplitude beyond its non-relativistic value. For intermediate- to large-amplitude solitons, a finite cool-electron temperature is found to destroy the balance between nonlinearity and dispersion, yielding soliton break-up. Also, only rarefactive electronacoustic soliton solutions of our equations are found, even though the relativistic beam provides a positive contribution to the nonlinear coefficient of the KdV equation, describing relativistic, nonlinear electron-acoustic waves.

scholarly journals Excitation of electron acoustic waves near the electron plasma frequency and at twice the plasma frequency

2000 ◽  
Vol 105 (A6) ◽  
pp. 12919-12927 ◽  
Author(s):  
D. Schriver ◽  
M. Ashour-Abdalla ◽  
V. Sotnikov ◽  
P. Hellinger ◽  
V. Fiala ◽  
...  
Keyword(s):  
Acoustic Waves ◽  
Plasma Frequency ◽  
Electron Plasma ◽  
Electron Plasma Frequency ◽  
Electron Acoustic Waves ◽  
Electron Acoustic

Two-soliton and three-soliton interactions of electron acoustic waves in quantum plasma

Pramana ◽  
2015 ◽  
Vol 86 (4) ◽  
pp. 873-883 ◽  
Author(s):  
KAUSHIK ROY ◽  
SWAPAN KUMAR GHOSH ◽  
PRASANTA CHATTERJEE
Keyword(s):  
Acoustic Waves ◽  
Quantum Plasma ◽  
Soliton Interactions ◽  
Electron Acoustic Waves ◽  
Electron Acoustic

Oblique propagating extraordinary spin-electron acoustic waves

2018 ◽  
Vol 25 (10) ◽  
pp. 102115 ◽  
Author(s):  
Pavel A. Andreev ◽  
S. V. Kolesnikov
Keyword(s):  
Acoustic Waves ◽  
Electron Acoustic Waves ◽  
Electron Acoustic

scholarly journals Plasma wave mediated attractive potentials: a prerequisite for electron compound formation

2014 ◽  
Vol 32 (8) ◽  
pp. 975-989 ◽  
Author(s):  
R. A. Treumann ◽  
W. Baumjohann
Keyword(s):  
Acoustic Waves ◽  
Attractive Potential ◽  
Necessary Condition ◽  
Lower Hybrid ◽  
Compound Formation ◽  
Electron Acoustic Waves ◽  
Heavy Electron ◽  
Electron Acoustic ◽  
Electron Compounds ◽  
Electron Compound

Abstract. Coagulation of electrons to form macro-electrons or compounds in high temperature plasma is not generally expected to occur. Here we investigate, based on earlier work, the possibility for such electron compound formation (non-quantum "pairing") mediated in the presence of various kinds of plasma waves via the generation of attractive electrostatic potentials, the necessary condition for coagulation. We confirm the possibility of production of attractive potential forces in ion- and electron-acoustic waves, pointing out the importance of the former and expected consequences. While electron-acoustic waves presumably do not play any role, ion-acoustic waves may potentially contribute to formation of heavy electron compounds. Lower-hybrid waves also mediate compound formation but under different conditions. Buneman modes which evolve from strong currents may also potentially cause non-quantum "pairing" among cavity-/hole-trapped electrons constituting a heavy electron component that populates electron holes. The number densities are, however, expected to be very small and thus not viable for justification of macro-particles. All these processes are found to potentially generate cold compound populations. If such electron compounds are produced by the attractive forces, the forces provide a mechanism of cooling a small group of resonant electrons, loosely spoken, corresponding to classical condensation.

Excitation and Decay of Electron Acoustic Waves

2006 ◽  
Author(s):  
Francesco Valentini ◽  
Thomas M. O’Neil ◽  
Daniel H. E. Dubin
Keyword(s):  
Acoustic Waves ◽  
Electron Acoustic Waves ◽  
Electron Acoustic
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