Large Amplitude Dust Ion Acoustic Solitons and Double Layers in Dusty Plasmas with Ion Streaming and High-Energy Tail Electron Distribution

Large amplitude dust ion acoustic （DIA） solitons as well as double layers （DLs） are studied in a dusty plasma having a high-energy-tail electron distribution. The influence of electron deviation from the Maxwellian distribution and ion streaming on the existence domain of solitons is discussed in the （M, f） space using the pseudo-potential approach. It is found that in the presence of streaming ions and for a fixed f, solitons may appear for larger values of M. This means that in the presence of ion streaming, high values of the Mach number are needed to have soliton. The DIA solitary waves profile is highly sensitive to the ion streaming speed. Their amplitude is found to decrease with an increase of the ion streaming speed. In addition, we find that the ion streaming effect may lead to the appearance of double layers. The results of this axticle should be useful in understanding the basic nonlinear features of DIA waves propagating in space dusty plasmas, especially those including a relative motion between species, such as comet tails and solar wind streams, etc.

Relativistic Magnetosonic Soliton in a Negative-Ion-Rich Magnetized Plasma

Two-dimensional （219） relativistic magnetosonic solitons in the negative-ion-rich plasma consisting of positive ions Ar＋, negative ions SF6 and electrons are investigated in the presence of an applied magnetic field Bo and can be described by a Kadomtse-Petviashvili （KP） equation in the weakly relativistic limit. The ratio of positive ion density to negative ion density has a marked influence on the amplitude φm and width W of the steady-state KP soliton. The interaction law of the nontrivial solitons with rich web structure is studied by the Wronskian determinant method.

Influence of Non-Maxwellian Particles on Dust Acoustic Waves in a Dusty Magnetized Plasma

In this paper an investigation into dust acoustic sofitary waves （DASWs） in the presence of superthermM electrons and ions in a magnetized plasma with cold dust gains and trapped electrons is discussed. The dynamic of both electrons and ions is simulated by the generalized Lorentzian （κ） distribution function （DF）. The dust grains are cold and their dynamics are studied by hydrodynamic equations. The basic set of fluid equations is reduced to modified Korteweg-de Vries （mKdV） equation using Reductive Perturbation Theory （RPT）. Two types of solitary waves, fast and slow dust acoustic soliton （DAS） exist in this plasma. Caiculations reveal that compressive solitary structures are possibly propagated in the plasma where dust grains are negatively （or positively） charged. The properties of DASs are also investigated numerically.

Electron acoustic solitary waves in unmagnetized nonthermal plasmas

Electron acoustic(EA)solitary waves(SWs)are studied in an unmagnetized plasma consisting of hot electrons(following Cairns-Tsalli distribution),inertial cold electrons,and stationary ions.By employing a reductive perturbation technique(RPT),the nonlinear Korteweg–de Vries(KdV)equation is derived and its SW solution is analyzed.Here,the effects of plasma parameters such as the nonextensivity parameter(q),the nonthermality of electrons(α),and the cold-to-hot electron density ratio(β)are investigated.