Characteristics Of Dust Acoustic Solitary Waves Research Articles

The effect of dust streaming on arbitrary amplitude solitary waves in superthermal polarized space dusty plasma

Abstract The impact of dust streaming and polarization force on dust acoustic solitary waves (DASWs) is examined in a non-magnetized dusty plasma made up of negatively charged dust, superthermal ions, and Maxwellian electrons. In the linear limit, the dispersion relation is derived and numerically analyzed. In order to explore the characteristics of arbitrary amplitude DASWs, a Sagdeev potential technique is used. It is explored how the existence domain and characteristics of the DASWs are affected by the polarization force connected to the superthermality index of ions and dust streaming. The relevance of the present study to space dusty plasma, in particular to Saturn’s F-ring, is highlighted.

Nonlinear propagation of dust-acoustic modes in a dusty plasma with the Kappa-Cairns polarization force effects

In this paper, the influence of Kappa-Cairns polarization force on solitary and periodic dust-acoustic (DA) waves is studied in a non-uniform dusty plasma containing negatively charged dust grains, Maxwellian electrons, and the Kappa-Cairns distributed ions. It is observed that in the presence of Kappa-Cairns distributed ions, the magnitude of the polarization force first increases as the spectral index increases and then decreases. The nonlinear Korteweg-de-Vries (K-dV) equation is obtained employing the reductive perturbation technique. The effects of polarization parameter (), Kappa-Cairns distribution parameters ( and ), and different ratios of ion to electron number densities () are investigated on the characteristics of DA solitary waves. We observed that the variations in the phase speed, amplitude, and width of DA solitons in the presence of the Kappa-Cairns polarization force are considerably different for case with respect to . The bifurcation theory of planar dynamical systems is also applied to investigate the existence of the solitary/periodic traveling wave in this plasma model. The phase portrait topology is illustrated for the K-dV equation. It is found that polarization force and other plasma parameters have a vital role in the traveling wave structures.

Nonlinear Dust Acoustic Waves in Strongly Coupled Quantum Dusty Plasmas

Using a set of fluid equations to describe the inertial dust grain component in dense collisionless unmagnetized quantum dusty plasmas, where the electrons and ions obey the Thomas-Fermi density distribution, the propagation characteristics of dust acoustic solitary waves (DASWs) are studied. First, a linear dispersion of dust acoustic wave (DAW) is obtained, and it is shown that the DAW is modified by a strongly coupled parameter. Then for small amplitude solitary waves, the Korteweg-de Vries equation is obtained by applying the reductive perturbation technique. For arbitrary amplitude solitary waves, the Sagdeev potential method is employed and the Sagdeev potential is analyzed. In both cases, the effect of dust coupling parameters on the characteristics of DASWs in our system are analyzed.

Non-extensive effects on the characteristics of dust-acoustic solitary waves in magnetized dusty plasma with two-temperature isothermal ions

The nonlinear Zakharov–Kuznetsov and the modified Zakharov–Kuznetsov equations are derived for dust-acoustic solitary waves (DASWs) in a magnetized four-component dusty plasma system comprising negatively charged cold dust, non-extensive electrons, and two-temperature thermal ions using standard reductive perturbation method. The combined effects of electron non-extensivity, strength of magnetic field, and its obliqueness on the DASWs profile are analyzed. Different ranges of non-extensive q-parameter are considered. Our results show that solitary waves, that their amplitude and width of which depend sensitively on the q-non-extensive parameter, can exist. Due to electron non-extensivity, our dusty plasma model can admit positive potential as well as negative potential solitons. The strength of magnetic field has no effect on the amplitude of solitary waves, whereas its obliqueness affects both amplitude and width of the solitary waves structure. Results show that the amplitude of soliton increases with increasing the velocity of soltion. For any magnitude of q there is an extremum for the direction of the magnetic field at which the width of soliton is maximum.

Dust-acoustic solitary structures in a magnetized dusty plasma with two-temperature nonextensive electrons

The nonlinear propagation of dust-acoustic (DA) waves in an obliquely propagating magnetized dusty plasma, containing nonextensively distributed electrons of distinct temperatures (namely lower and higher temperature nonextensive electrons), negatively charged mobile dust grains, and Maxwellian ions, is rigorously studied and analyzed by deriving the Zakharov-Kuznetsov equation. It is found that the characteristics of the DA solitary waves (DASWs) are significantly modified by the external magnetic field, obliqueness of the system, nonextensivity of the electrons, electron temperature-ratios, and the respective number densities of two species of electrons. The results obtained from this analysis can be employed in understanding and treating the structures and the characteristics of DASWs both in laboratory and astrophysical plasma system.

Planar and nonplanar dust acoustic solitary waves in electron–positron–ion–dust plasmas

Planar and nonplanar dust acoustic (DA) solitary waves are studied in an unmagnetized plasma consisting of electrons, positrons, ions and dust species. This is done by deriving the modified Kortweg–de Vries (mKdV) equation under the small amplitude perturbation expansion method. It is found that in the presence of positrons, DA hump-like solitary waves may also exist under suitable conditions. It is also observed that the positron concentration and the ratio of ion-to-electron temperature significantly modify the propagation characteristics of DA solitary waves. The range of plasma parameters for which we obtain hump-like solitons are found numerically. The present investigation may have relevance in both laboratory and astrophysical plasmas.

Localized coherent nonlinear wave structures in dusty plasma with non-thermal ions

AbstractIn the present research paper, the characteristics of dust-acoustic solitary waves (DASWs) and double layers (DLs) are studied. Ions are treated as non-thermal and variable dust charge is considered. The Korteweg–de Vries equation is derived using a reductive perturbation method. It is noticed that compressive solitons are obtained up to a certain range of relative density δ (=ni0/ne0) beyond which rarefactive solitons are observed. The study is further extended to investigate the possibility of DLs. Only compressive DLs are permissible. Both DASWs and DLs are sensitive to variation of the non-thermal parameter.

Dust-acoustic solitary waves in a finite temperature dusty plasma with variable dust charge and two temperature ions

In this paper, the characteristics of dust-acoustic solitary waves in dusty plasma are studied. Dust charge and temperature are treated as variables. The authors have used the pseudopotential method to investigate the possibility of compressive as well as rarefactive solitons. An expression for the pseudopotential has been derived. The pseudopotential is a function of the Mach number, the relative temperature of low and high ion components, the relative ion concentration of dust charge and the temperature. Numerical computation shows that for the chosen set of parameters, only compressive solitons exist and their amplitudes increase with increasing Mach number. An increase in the dust temperature results in the disappearance of the compressive soliton. It is the only small parameter regime where compressive as well rarefactive solitons coexist. The effect of the relative ion temperature on solitons is also investigated. In the small amplitude limit, an increase in the dust temperature leads to a transition from compressive to rarefactive solitons.