Effect of electric field inhomogeneity on kinetic Alfven wave in an inhomogeneous magnetosphere

Abstract

The effect of electric field in-homogeneity perpendicular to the ambient magnetic field on Kinetic Alfven waves in the presence of ion and electron beam velocities are investigated. In the present study we have adopted the particle aspect approach to investigate the trajectories of charged particles in the electromagnetic field of a kinetic Alfven wave. Expressions are derived for the field-aligned current, the perpendicular current and the dispersion relation. Energy conservation method was used to obtain the growth/damping rate of the wave. The effect of inhomogeneity of electric field and electron and ion beam velocities are discussed. In present study, we assumed that the plasma is an anisotropic and with low-β. The results are discussed for the space plasma parameter appropriate to the auroral acceleration region of the earth’s magnetosphere.