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The higher-order, low-amplitude inertial Alfvén wave (IAW) dressed soliton and chaos are investigated in a magnetized plasma. In the linear limit, the dispersion relation for propagation of IAWs in plasmas is also obtained in the presence of electron thermal effects and illustrated numerically. It is found that the electron inertial length plays an important role for wave dispersion effects and its phase speed is increased on including the electron temperature in the model. The reductive perturbation method is employed to obtain the first-order IAW Korteweg-de Vries (KdV) soliton and second-order dressed soliton solutions analytically, which gives electron density dip (or rarefactive) structure and moves with super Alfvénic speed in plasmas. The numerical illustrations of the KdV and dressed IAW solitons are also presented by using the laboratory and space plasma parameters given in the literature. Furthermore, a numerical study of quasi-periodicity and chaotic behaviour of IAWs in the presence of external periodic force is also discussed in detail. The effects of plasma beta (which depends on plasma density, electron temperature, and magnetic field intensity) and obliqueness of the wave propagation on the formation of nonlinear Alfvénic wave structures have also been presented. [ABSTRACT FROM AUTHOR]

The interaction of Kinetic Alfvén (KA) wave solitons is examined in a finite β (me/mi < β < 1) electron-ion plasma with kappa distributed electrons. Following the extended Poincaré-Lighthill-Kuo method, coupled Korteweg–de Vries (KdV) equations are derived for the interaction of two moving opposite Kinetic Alfvénic solitons and the corresponding phase shifts are estimated. The procedure is then extended to the multiple soliton interaction of Kinetic Alfvén waves. By using the Hirota bilinear method, the solution of two-sided double and two-sided triple KA KdV solitons and their corresponding phase shifts are obtained. The profiles of head-on collision in multiple soliton situations are shown; the present model supports only compressive sub-Alfvénic soliton structures. It is found that plasma β, obliqueness, and the superthermality index significantly alter the phase shifts (due to head-on and overtaking collisions). The magnitude of the phase shift due to overtaking collision is more compared to that with the head-on collision. The present study is relevant to space and laboratory plasma underpinning sub-Alfvénic soliton. [ABSTRACT FROM AUTHOR]

The dynamical characteristics of large amplitude ion-acoustic waves are investigated in a magnetized plasma comprising ions presenting space asymmetry in the equation of state and non-Maxwellian electrons. The anisotropic ion pressure is defined using the double adiabatic Chew-Golberger-Low theory. An excess in the superthermal component of the electron population is assumed, in agreement with long-tailed (energetic electron) distribution observations in space plasmas; this is modeled via a kappa-type distribution function. Large electrostatic excitations are assumed to propagate in a direction oblique to the external magnetic field. In the linear (small amplitude) regime, two electrostatic modes are shown to exist. The properties of arbitrary amplitude (nonlinear) obliquely propagating ion-acoustic solitary excitations are thus investigated via a pseudomechanical energy balance analogy, by adopting a Sagdeev potential approach. The combined effect of the ion pressure anisotropy and excess superthermal electrons is shown to alter the parameter region where solitary waves can exist. An excess in the suprathermal particles is thus shown to be associated with solitary waves, which are narrower, faster, and of larger amplitude. Ion pressure anisotropy, on the other hand, affects the amplitude of the solitary waves, which become weaker (in strength), wider (in spatial extension), and thus slower in comparison with the cold ion case. [ABSTRACT FROM AUTHOR]

The head on collision between two dust ion acoustic (DIA) solitary waves, propagating in opposite directions, is studied in an unmagnetized plasma constituting adiabatic ions, static dust charged (positively/negatively) grains, and non-inertial kappa distributed electrons. In the linear limit, the dispersion relation of the dust ion acoustic (DIA) solitary wave is obtained using the Fourier analysis. For studying characteristic head-on collision of DIA solitons, the extended Poincare-Lighthill-Kuo method is employed to obtain Korteweg-de Vries (KdV) equations with quadratic nonlinearities and investigated the phase shifts in their trajectories after the interaction. It is revealed that only compressive solitary waves can exist for the positive dust charged concentrations while for negative dust charge concentrations both the compressive and rarefactive solitons can propagate in such dusty plasma. It is found that for specific sets of plasma parameters, the coefficient of nonlinearity disappears in the KdV equation for the negative dust charged grains. Therefore, the modified Korteweg-de Vries (mKdV) equations with cubic nonlinearity coefficient, and their corresponding phase shift and trajectories, are also derived for negative dust charged grains plasma at critical composition. The effects of different plasma parameters such as superthermality, concentration of positively/negatively static dust charged grains, and ion to electron temperature ratio on the colliding soliton profiles and their corresponding phase shifts are parametrically examined. [ABSTRACT FROM AUTHOR]

The nonlinear ion-acoustic wave excitation and its stability analysis are investigated in a magnetized quantum plasma with exchange-correlation and Bohm diffraction effects of degenerate electrons in the model. Using reductive perturbation technique, the Zakharov-Kuznetsov (ZK) equation is derived for two dimensional propagation of ion-acoustic wave in a magnetized quantum plasma. It is found that the phase speed, amplitude and width of the nonlinear ion-acoustic wave structures are affected in the presence of exchange-correlation potential in the model. The stability analysis of the 2D ion-acoustic wave pulse is also presented. It is found that growth rate of the first and second order instabilities of 2D ion acoustic wave soliton is enhanced with the inclusion of exchange-correlation potential effect in the model. • Two dimensional propagation of ion acoustic soliton in a magnetized dense plasma is studied. • The quantum effects of electrons such as Bohm diffraction and exchange-correlation potential are included in the model. • The reductive perturbation method (RPM) is used to derive the Zakharov-Kuznetsov (ZK) equation. • The growth rates of first and second order instabilities of 2D soliton with angle of transverse perturbations to the magnetic field are discussed. • Exchange-correlation effect of electrons plays an effective role on the stability of the 2D soliton in magnetized dense plasma. [ABSTRACT FROM AUTHOR]