Electron density perturbations by electrostatic waves and their effect on plasma waves in a dusty plasma

Interaction of high-frequency electrostatic waves and a static electron density perturbation is considered in a dusty plasma including the effect of dusty charging. The static electron density perturbation is created by the low-frequency ponderomotive force in the parameter regime of a dusty plasma where the electron Debye length and temperature are much greater than the ion Debye length and temperature, respectively. The electron momentum damping rate (ν e ) due to the high-frequency charging process of the dust grains can be much greater or much smaller than the electron plasma frequency or wave frequency (ω) under consideration, depending upon the parameters of the dusty plasma. When ω>>ν e , the nonlinear high-frequency wave coupled with the electron density perturbation is described by a nonlinear Schrödinger equation, which bears a modulationally unstable envelope. When ω<<ν e , the high-frequency electrostatic wave reduces to a dust charge relaxation mode and the coupled nonlinear wave equation yields a solution of envelope shocks.