الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
A theoretical study is presented of the nonlinear self-modulation of low-frequency electrostatic dust acoustic (DA) waves propagating in a dusty plasma exposed to an external ion beam. By employing the derivative expansion perturbation method, a nonlinear Schrödinger equation (NLSE) is derived for the electric potential wave amplitude. Both dispersion and nonlinearity coefficients of the NLSE are explicit functions of the carrier wavenumber and of relevant physical parameters background species density and temperature. The modulation instability of the NLSE is investigated. It is found that the presence of the ion beam species reduces the stable domain of the DA waves and the stable DA waves are created at higher wavenumber, k. Increasing ion beam temperature results as interment of the wave dispersion and nonlinearity and the wave frequency. Also it widens the stability domain of the DA waves. A brief discussion is provided related to the application of the current findings in either space plasma (Herbig--Haro object) or some plasma experiments.
Properties of dust-acoustic solitary waves in a warm dusty plasma are analyzed by using the hydrodynamic model for massive dust grains, electrons, ions, and streaming ion beam. For this purpose, Korteweg-de Vries (KdV) equation for the first-order perturbed potential and linear inhomogeneous KdV-type equation for the second-order perturbed potential have been derived and their analytical solutions are presented. In order to show the characteristics of the dust-acoustic solitary waves are influenced by the plasma parameters, the relevant numerical analysis of the KdV and linear inhomogeneous KdV-type equations are obtained. The dust-acoustic solitary waves, as predicted here, may be associated with the nonlinear structures caused by the interaction of polar jets with the interstellar medium, which is known as Herbig--Haro objects.