Electromagnetic vortices in electron-positron-ion plasmas with shear flow

Abstract

Two coupled nonlinear equations for a perturbed electromagnetic field in an electron-positron-ion plasma with shear flow, embedded in a nonuniform magnetic field, are derived and solved analytically. The nonlinear solutions of these equations are found in the form of tripolar vortices. The linear instability condition is also discussed. It is found that the presence of ions can play a significant role in nonlinear dynamics, even if the density of ions is of the order of 10−3 as compared to the densities of the lighter species.