الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Effect of positive ( negative) charged dust cyclotron frequencies and the positive (negative) dust viscosity coefficients on the propagation of dust-acoustic waves (DAWs) in a homogeneous system of a magnetized collisionless plasma consisting of a four-component dusty plasma with massive, micron-sized, positively, negatively dust grains, elcetron and ion have been investigated. The reductive perturbation method was employed to reduce the basic set of fluid equations to the Zakharov Kuznetsov (ZK) equation. It was found that the presence of positive ( negative) charged dust cyclotron frequencies and the positive (negative) dust viscosity coefficients significantly modify the basic properties of solitary structure. A theoretical investigation was carried out for contribution of the higher-order nonlinearity. A ZK equation that contains the lowest-order nonlinearity and dispersion is derived from the lowest order of perturbation and a linear inhomogeneous (ZK-type) equation that accounts for the higher- order nonlinearity and dispersion is obtained. A stationary solution for equations resulting from higher-order perturbation theory has been found using the renormalization method. It was noted that the lowest order amplitude of the DAWs solitons is independent of the magnitude of the external magnetic field while the higher-order amplitude of the DAWs solitons is dependent mainly on the magnitude of the external magnetic field. For two dimensional small amplitude dust-acoustic solitary waves (DAWs), the Kadomstev- Petviashvili (KP) equation was obtained and the energy of two temperatures charged dusty grains were computed. In the presence of kinematic viscosity of positive ( negative) charged dust, the KdV-Burgers was derived. It is found that solitary and shock waves can be produced in this medium. The effects of important parameters such as kinematic viscosity of positive ( negative) charged dust on the properties of shock waves are discussed. The present investigation can be of relevance to the electrostatic solitary structures observed in various space plasma environments such as cometary tails, upper mesosphere and Jupiter.s magnetosphere.