Numerical simulation of the individual mode evolution in a slab jet

Abstract

Two-dimensional magnetohydrodynamic (MHD) simulations are performed to study the evolution of the Kelvin-Helmholtz (KH) instability for a slab jet moving parallel to the uniform magnetic field. Surface modes are excited and the time evolution of the individual mode is observed. The instability is very disruptive when the excited perturbations on the two side boundaries are antisymmetric. The long term evolution of the antisymmetric perturbation shows a kink-like magnetic field structure after multiple reconnection events, while the symmetric perturbation yields wavy signatures only around the jet boundary. These MHD results are markedly different from the hydrodynamic results, although the magnetic field intensity in the present case is very small.