Quick triggering of magnetic reconnection mediated by lower hybrid drift instability

Abstract

Carrying out a large scale 3D full kinetic simulation, we have shown that the effects of lower-hybrid waves at the edges of the current sheet provide a quick triggering of magnetic reconnection even in ion-scale current sheets. A thin embedded electron current layer is formed as a result of the non-linear evolution of the lower hybrid drift instability, which is sustained by accelerated meandering electrons around the neutral sheet, and the emergence of a thin electron current layer is subject to the quick reconnection triggering. However. there may be an upper-limit to the current sheet thickness for this type of quick triggering mediated by the lower-hybrid-drift instability alone because the lower-hybrid-drift wave activity becomes weaker in a thicker current sheet. To evaluate whether the quick triggering mechanism mediated by the lower-hybrid-drift instability is truly realistic, we performed a parametric study of magnetic reconnection with the lower hybrid drift instability. Consequently, we confirmed that the proposed scenario of the quick reconnection triggering is available with a real ion-electron mass ratio m/sub i//m/sub e/=1836. We also found that the upper-limit of the current sheet thickness depends sensitively on the strength of the guide magnetic field.