Current-driven Alfv,n waves in dusty magnetospheric plasmas

It is shown that the sheared flow of electrons and ions in the presence of heavy stationary dust gives rise to unstable Alfv,n waves. The coupling of newly studied low frequency electrostatic current-driven mode with the electromagnetic Alfv,n and drift waves is investigated. The instability conditions and the growth rates of both inertial and kinetic Alfv,n waves are estimated. The theoretical model is applied to the night side boundary regions of Jupiter's magnetosphere which contain positive dust. The growth rates increase with increase in sheared flow speed. In the nonlinear regime, both inertial and kinetic Alfv,n waves form dipolar vortices whose speed and amplitude depend upon the magnitude of the zero-order current.