Nonlinear Plasma Waves Research Articles

Effect of q-nonextensive distribution of electrons on dust-ion acoustic solitons

The propagation of nonlinear waves in plasmas consisting of a cold electron fluid and nonextensive hot electrons and stationary ions is studied. By using the reductive perturbation theory, the Korteweg-de Vries (KdV) equation is derived. It is shown that the amplitude of solitary waves of the KdV equation diverges at the critical values of plasma parameters. We derive solitons of a modified Korteweg-de Vries (mKdV) equation with finite amplitude in this situation. It is found that both compressive and rarefractive solitons as well as double layers exist depending on the q-nonextensive parameter. The q-parameter also affects the double layers. Our investigation is of wide relevance to astronomers and space scientists working on interstellar space plasmas.

Effect of nonextensive electron and ion on dust acoustic rogue waves in dusty plasma of opposite polarity

Propagation of nonlinear dust-acoustic waves in a magnetized collisionless plasma having positively, negatively charged dust grains and nonextensive distributed electrons and ions has been investigated. A reductive perturbation method is used to obtain a nonlinear Korteweg-de Vries (KdV) equation describing the model. The dynamics of the modulational instability gives rise to the formation of rogue waves that is described by a nonlinear Schrodinger equation. The dependence of rogue waves profiles on positive and negative charged dust cyclotron frequencies, nonextensive parameters of electrons and ions is investigated numerically. The result of the present investigation may be applicable to some plasma environments, such as cometary tails and upper mesosphere.

Rogue waves for Kadomstev-Petviashvili equation in electron-positron-ion plasma

The nonlinear ion-acoustic waves in plasma having excess super-thermal electrons and positrons have been investigated. Reductive perturbation method is used to obtain a Kadomstev-Petviashvili equation describing the system. The dynamics of the modulationally unstable wave packets described by the Kadomstev-Petviashvili equation gives rise to the formation of rogue excitation that is described by a nonlinear Schrodinger equation. The dependence of rogue waves profiles on the system parameters investigated numerically. The result of the present investigation may be applicable to some plasma environments, such as galactic clusters, interstellar medium.

A nonlinear model for magnetoacoustic waves in dense dissipative plasmas with degenerate electrons

The properties of nonlinear fast magnetoacoustic waves in dense dissipative plasmas with degenerate electrons are studied theoretically in the framework of the Zabolotskaya-Khokhlov (ZK) equation for small but finite amplitude excitations. Shock-like solutions of the ZK equation are obtained and are applied to parameters relevant to white dwarf stars.

Non-linear Langmuir waves in a warm quantum plasma

A non-linear differential equation describing the Langmuir waves in a warm quantum electron-ion plasma has been derived. Its numerical solutions of the equation show that ordinary electronic oscillations, similar to the classical oscillations, occur along with small-scale quantum Langmuir oscillations induced by the Bohm quantum force.

Kinetic simulations and reduced modeling of longitudinal sideband instabilities in non-linear electron plasma waves

Kinetic Vlasov simulations of one-dimensional finite amplitude Electron Plasma Waves are performed in a multi-wavelength long system. A systematic study of the most unstable linear sideband mode, in particular its growth rate γ and quasi- wavenumber δk, is carried out by scanning the amplitude and wavenumber of the initial wave. Simulation results are successfully compared against numerical and analytical solutions to the reduced model by Kruer et al. [Phys. Rev. Lett. 23, 838 (1969)] for the Trapped Particle Instability (TPI). A model recently suggested by Dodin et al. [Phys. Rev. Lett. 110, 215006 (2013)], which in addition to the TPI accounts for the so-called Negative Mass Instability because of a more detailed representation of the trapped particle dynamics, is also studied and compared with simulations.

Modulational stability of electron plasma wave spectra

Analytical models for weakly nonlinear electron plasma waves are considered in order to obtain dynamic equations for the space-time evolution of their local power spectra. The model contains the wave kinetic equation as a limiting case for slow, long wavelength modulations. It is demonstrated that a finite spectral width in wavenumbers has a stabilizing effect on the modulational instability. The results invite a simple heuristic relation between the spectral width and the root-mean-square amplitude of stable stationary turbulent Langmuir wave spectra. A non-local average dispersion relation is derived as a limiting form by using the formalism developed for the spectral dynamics.

Do nonlinear waves evolve in a universal manner in dusty and other plasma environments?

Using a fluid theory approach, this article provides a comparative study on the evolution of nonlinear waves in dusty plasmas, as well as other plasma environments, viz electron-ion, and electron-positron plasmas. Where applicable, relevance to satellite measurements is pointed out. A range of nonlinear waves from low frequency (ion acoustic and ion cyclotron waves), high frequency (electron acoustic and electron cyclotron waves) in electron-ion plasmas, ultra-low frequency (dust acoustic and dust cyclotron waves) in dusty plasmas and in electron-positron plasmas are discussed. Depending upon the plasma parameters, saw-tooth and bipolar structures are shown to evolve.

Linear and nonlinear dust acoustic waves in an inhomogeneous magnetized dusty plasma with nonextensive electrons

The propagation of both linear and nonlinear dust acoustic waves (DAWs) in an inhomogeneous magnetized collisional and warm dusty plasma (DP) consisting of Boltzmann ions, nonextensive electrons, and inertial dust particles is investigated. The number density gradients of all DP components besides the inhomogeneities of electrostatic potential and the initial dust fluid velocity are taken into account. The linear dispersion relation and a nonlinear modified Zakharov-Kusnetsov (MZK) equation governing the propagation of the three-dimensional DAWs are derived. The analytical solution of the MZK reveals the creation of both compressive and rarefactive DAW solitons in the proposed model. It is found that the inhomogeneity dimension parameter and the electron nonextensive parameter affect significantly the nonlinear DAW's amplitude, width, and Mach number. The relations of our findings with some astrophysical situations have been given.

Effects of variable dust size, charge and mass on the characteristics of dust acoustic solitary waves in a magnetized dusty plasma

The effect of dust size, mass and charge distributions on the characteristics of nonlinear dust acoustic solitary waves (DASW) in a two-temperature ion dusty plasma has been studied analytically. The mass and electrical charge of dust particles are assumed to be proportional with their size. Plasma is embedded in an external magnetic field with variable direction. Using a reductive perturbation method, the Zakharov–Kuznetsov (ZK) equation is derived and its solitary answers are extracted. The coefficients of the nonlinear term of the ZK equation are affected strongly by the size of dust particles when the relative size (the ratio of the largest dust radius to smallest dust radius) is less than 2. Both the width and amplitude of DASW increase with increasing relative size. The cyclotron frequency of the dust changes with the relative size of the dust particles. DASW width is influenced by the magnitude as well as direction of the external magnetic field, while its amplitude is independent of the magnitude of the external magnetic field. At each strength of the external magnetic field, there is an optimum magnitude for its direction at which the width of DASW is maximum.

On the Nonlinear Plasma Waves in the High-Frequency Wave Heating of the Ionosphere

In the O-mode high-frequency (HF) heating of the ionosphere, parametric instabilities were excited to generate plasma waves. Among those, Langmuir waves and ion acoustic waves were evidenced by the HF enhanced plasma lines and HF enhanced ion lines in the recorded spectra of the ultra high frequency (UHF)/very high frequency (VHF) backscatter radars. These waves can grow to large amplitudes and become nonlinear waves. The nonlinear Schrodinger equation and Korteweg-de Vries equation governing the nonlinear evolution of Langmuir waves and ion acoustic waves are derived and solved. It is shown that the solutions of these equations can be either periodic or solitary depending on the physical conditions. The analyses show the conditions of generating Langmuir soliton and ion acoustic soliton.

Oblique collision effects on nonlinear quantum dust-acoustic solitary waves in magnetized dense dusty plasmas

The oblique collision of nonlinear quantum dust-acoustic (NQDA) solitary waves in a three-dimensional (3D) magnetized dense dusty plasma is investigated. Furthermore, two coupled Kortwege–de Vries equations for describing our model and the analytical phase shifts after the oblique collision of two NQDA solitary waves are derived using the extended Poincare–Lighthill–Kuo (PLK) method. The modification in the phase shift and the trajectory of the NQDA solitary waves structures due to the inclusion of oblique collision and external magnetic field are discussed numerically. The numerical results are applied to high density astrophysical situations such as in superdense white dwarfs.

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Effects of spherical geometry and two temperature electrons on dust acoustic waves

The nonlinear dust acoustic waves in dusty plasmas with two temperature electrons and the combined effects of bounded spherical geometry and the transverse perturbation are studied. Using the perturbation method, a spherical Kadomtsev-Petviashvili (SKP) equation that describes the dust acoustic waves is deduced.

Study on Nonlinear Ion-acoustic Solitary Wave Phenomena in Slow Rotating Plasma

Nonlinear waves have been an important subject in the field of astroplasmas under the action ofCoriolis force because of rotation could be the progenitor of many heuristic feature on waves. Our main interest is to study the nonlinear ion -acoustic wave in a rotating plasma. Pseudopotential analysis has been used to derive the Sagdeev -like wave equation which, in turn, becomes the tool to study the different nature of nonlinear plasma waves. Special methods have been developed successfully to derive different kinds of solitary wave solutions. Main emphasis has been given to the interaction of Coriolis force to the changes of coherent structures of solitary waves e.g. Compressive and rarefactive solitary waves along with their explosions or collapses. It has shown that the variation of rotation affects the nonlinear wave modes and causeway exhibits shockwaves, double layers, sinh -wave, and formation of sheath structure in dynamical system. It has shown that the rotation, however small in magnitude, generatesa narrow wave packet with the generation of high energy therein which, in turn, yields the phenom ena of radiating soliton. It finds that the Coriolis force might be the cause in blowing up the ion -acoustic pulses and could be related the phenomena of solar burst. Thusthe work has the potential interest to study the nonlinear waves in astroplasmas wherein Coriolis force is present with a view to rekindle the soliton dynamics in space plasmas.

Solitary wave solution for a class of dusty plasma

A class of nonlinear solitary waves in dusty plasma is considered. Firstly, a non-disturbed solitary wave solution is stated. Then the iteration is constructed by using the homotopic mapping, and the traveling wave solution of the nonlinear single-disturbed solitary waves in dusty plasma is obtained. Finally, every degree of approximate solutions for corresponding single solitary wave model can be found.

Auto-Backlund transformations and new exact travelling wave solutions of Kadomtsev-Petviashvili equation for nonlinear dust acoustic solitary waves in dust plasmas with variable dust charge and two temperature ions

Auto-Backlund transformations and new exact travelling wave solutions of Kadomtsev-Petviashvili equation for nonlinear dust acoustic solitary waves in dust plasmas with variable dust charge and two temperature ions

A multidimensional numerical scheme for two-fluid relativistic magnetohydrodynamics

The paper describes an explicit multi-dimensional numerical scheme for Special Relativistic Two-Fluid Magnetohydrodynamics of electron-positron plasma and a suit of test problems. The scheme utilizes Cartesian grid and the third order WENO interpolation. The time integration is carried out using the third order TVD method of Runge-Kutta type, thus ensuring overall third order accuracy on smooth solutions. The magnetic field is kept near divergence-free by means of the method of generalized Lagrange multiplier. The test simulations, which include linear and non-linear continuous plasma waves, shock waves, strong explosions and the tearing instability, show that the scheme is sufficiently robust and confirm its accuracy.

Effect of ion kinematic viscosity on large amplitude dust ion acoustic solitary waves

Nonlinear dust ion acoustic solitary waves (DIASW) in dusty plasma are studied incorporating kinematic viscosity, using Sagdeev’s pseudopotential approach. The effects of kinematic viscosity and the nonextensive parameter q on the features of DIASW are investigated in some detail.

Nonlinear electrostatic excitations in magnetized dense plasmas with nonrelativistic and ultra-relativistic degenerate electrons

Linear and nonlinear electrostatic waves in magnetized dense electron-ion plasmas are studied with nonrelativistic and ultra-relativistic degenerate and singly, doubly charged helium (He+, He++) and hydrogen (H+) ions, respectively. The dispersion relation of electrostatic waves in magnetized dense plasmas is obtained under both the energy limits of degenerate electrons. Using reductive perturbation method, the Zakharov-Kuznetsov equation for nonlinear propagation of electrostatic solitons in magnetized dense plasmas is derived for both nonrelativistic and ultra-relativistic degenerate electrons. It is found that variations in plasma density, magnetic field intensity, different mass, and charge number of ions play significant role in the formation of electrostatic solitons in magnetized dense plasmas. The numerical plots are also presented for illustration using the parameters of dense astrophysical plasma situations such as white dwarfs and neutron stars exist in the literature. The present investigation is important for understanding the electrostatic waves propagation in the outer periphery of compact stars which mostly consists of hydrogen and helium ions with degenerate electrons in dense magnetized plasmas.