Effects of out-of-plane shear flows on fast reconnection in a two-dimensional Hall magnetohydrodynamics model

Abstract

Effects of out-of-plane shear flows on fast magnetic reconnection in Hall magnetohydrodynamics approximation are studied in a slab model with an initial Harris sheet equilibrium. It is found that the out-of-plane shear flows can also generate a series of out-of-plane magnetic perturbations that significantly modify the out-of-plane quadrupolar magnetic perturbation induced by the Hall effect in magnetic reconnection. The modification to out-of-plane magnetic perturbations then considerably affects the magnetic reconnection process. Particularly, flows along the X-line can either enhance or reduce the reconnection rate, even altering the X-point to an O-point and resulting in a secondary island. The impact on satellite observations is also discussed.