scholarly journals The Excitation of Ion-acoustic Waves by a Magnetic Pump in Cylindrical Geometry

1983 ◽  
Vol 36 (5) ◽  
pp. 675
Author(s):  
NF Cramer ◽  
IJ Donnelly
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
Acoustic Waves ◽  
Pump Wave ◽  
Modulational Instability ◽  
Collisionless Plasma ◽  
Cylindrical Geometry ◽  
Alfvén Waves ◽  
Ion Acoustic Waves ◽  
Ion Acoustic

The modulational, parametric and purely 8rowing mode instabilities of a magnetic pump with a finite radial wavenumber in cylindrical geometry are investigated. The modulational instability is compared with the instability of a parallel propagating pump wave, and the growth rates are found to be similar. The growth rate of a pair of ion-acoustic waves is shown to be zero for a collisionless plasma, in agreement with less general results found previously. The growth rate in the collisional case is found to be nonzero. The purely growing mode growth rate is calculated for excitation of ionacoustic plus torsional Alfven waves.

Nonlinear interaction of slow Alfvén wave with ion acoustic wave and applications to space plasma

2013 ◽  
Vol 79 (5) ◽  
pp. 833-836 ◽  
Author(s):  
B. K. DAS ◽  
R. P. SHARMA ◽  
N. YADAV
Keyword(s):  
Acoustic Waves ◽  
Analytical Study ◽  
Pump Wave ◽  
Modulational Instability ◽  
Solar Wind Plasma ◽  
Alfven Wave ◽  
Ion Acoustic Waves ◽  
Ion Acoustic Wave ◽  
Ion Acoustic ◽  
Model Equations

AbstractThe paper is concerned with the analytical study of nonlinear coupling of slow Alfvén wave (SW) with ion acoustic waves (IAWs) in high-β and low-β plasmas. Here the pump wave (SW) number density gets perturbed in the presence of IAW. The model equations of IAW and SW turn out to be the modified Zakharov system of equations when the ponderomotive nonlinearities are incorporated in the IAW and SW dynamics. Growth rate of modulational instability has been calculated. The relevance of these investigations for solar wind plasma and solar coronal plasma has also been discussed.

Modulational instability of ion-acoustic waves in fully relativistic two-component plasma

2015 ◽  
Vol 81 (3) ◽  
Author(s):  
B. Ghosh ◽  
S. Banerjee
Keyword(s):  
Growth Rate ◽  
Acoustic Waves ◽  
Relativistic Effect ◽  
Modulational Instability ◽  
Perturbation Technique ◽  
Multiple Scale ◽  
Nls Equation ◽  
Ion Acoustic Waves ◽  
Ion Acoustic ◽  
Component Plasma

Nonlinear amplitude modulation of ion-acoustic waves (IAWs) in a fully relativistic unmagnetized two-fluid plasma has been theoretically studied by using complete set of fully relativistic dynamic equations. To describe the nonlinear evolution of the wave envelope a nonlinear Schrödinger (NLS) equation is derived by using standard multiple scale perturbation technique. Using this equation it is shown that the wave becomes modulationally unstable as the wavenumber exceeds certain critical value. This critical wavenumber is found to decrease with increase in relativistic effect. The instability growth rate has also been calculated numerically for different values of plasma drift velocity. The growth rate is shown to decrease with increase in the relativistic effect.

scholarly journals Modulation Instability of Ion-Acoustic Waves in Plasma with Nonthermal Electrons

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Basudev Ghosh ◽  
Sreyasi Banerjee
Keyword(s):  
Acoustic Waves ◽  
Modulational Instability ◽  
Perturbation Technique ◽  
Collisionless Plasma ◽  
Multiple Scale ◽  
Ion Temperature ◽  
Nls Equation ◽  
Ion Acoustic Waves ◽  
Nonthermal Electrons ◽  
Ion Acoustic

Modulational instability of ion-acoustic waves has been theoretically investigated in an unmagnetized collisionless plasma with nonthermal electrons, Boltzmann positrons, and warm positive ions. To describe the nonlinear evolution of the wave amplitude a nonlinear Schrödinger (NLS) equation has been derived by using multiple scale perturbation technique. The nonthermal parameter, positron concentration, and ion temperature are shown to play significant role in the modulational instability of ion-acoustic waves and the formation of envelope solitons.

Modulational instability of ion acoustic waves in the presence of density gradients

1979 ◽  
Vol 57 (5) ◽  
pp. 642-644 ◽  
Author(s):  
I. R. Durrani ◽  
G. Murtaza ◽  
H. U. Rahman
Keyword(s):  
Density Gradient ◽  
Acoustic Waves ◽  
Schrodinger Equation ◽  
Modulational Instability ◽  
Collisionless Plasma ◽  
Higher Order ◽  
Density Gradients ◽  
Ion Acoustic Waves ◽  
Ion Acoustic ◽  
Non Linear

Using the Krylov–Bogoliubov–Mitropolsky method of perturbation for weak non-linearities, we study the modulational instability of ion-acoustic waves in a collisionless plasma in the presence of a density gradient. We find that the density gradient of second or higher order of perturbation does not effect the dispersion and the non-linearity coefficients in the non-linear Schrödinger equation.

Sign in / Sign up

Export Citation Format

Share Document