Magnetic reconnection within MHD-scale Kelvin–Helmholtz vortices triggered by electron inertial effects

In understanding the structure of an MHD-scale Kelvin–Helmholtz (KH) vortex, magnetic reconnection within the vortex must not be neglected. Here, we have performed two-dimensional two-fluid simulations including finite electron inertial effects to investigate this issue. An MHD-scale velocity shear is set up and evolution of MHD-scale KH mode is followed with in-plane magnetic component taken into account. In this study, we focus on three basic cases with different initial magnetic configuration. In all cases, when the Alfven Mach number of the shear is strong enough, magnetic reconnection occurs spontaneously within the vortex by the electron inertial effects. The critical Alfven Mach number for the reconnection is found to depend on the initial magnetic configuration.