الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 18 |  |  |
| | | from | 18 | | |
Abstract
The derivative expansion perturbation method is applied to a cold plasma system consisting of dust grains with varying dust charge, electrons and two species of ions with the same mass and charge but with different temperatures. The basic system of equations is reduced to a nonlinear Schrödinger type (NLST) equation. The effects of the of the temperature of low-temperature ions on the system parameters, e.g. angular frequency, group velocity, dispersion coefficient, and the nonlinear coefficient are investigated. It is found that the presence of low-temperature ions enhances the stability of the system.
The small wave number limit of the coefficients of the nonlinear Schrödinger equation is obtained. Moreover, using the reductive perturbation technique, we derived the Korteweg-de Vries (KdV) equation. The oscillatory solution of this equation is obtained using a derivative expansion method.
It is found that the coefficients of the nonlinear Schrödinger type equation obtained from the oscillatory solution of the KdV equation agree exactly with the small wave number limit of the coefficients of the nonlinear Schrödinger equation obtained before. The previous mentioned method is used also to derive a nonlinear Schrödinger type equation for a cold plasma system consisting of dust grains with charge fluctuation, isothermal electrons and two species of ions fluid with the same mass and charge but different temperatures.
The effects of the temperature of low-temperature ions on the system parameters, e.g. angular frequency, group velocity, and dispersion coefficient have been studied. Also it is found that the existence of low-temperature ions enhances the instability of the system.