FORMATION OF RECONNECTION LAYER AT THE DAYSIDE MAGNETOPAUSE

A two-dimensional (2-D) hybrid simulation is carried out to study the formation and structure of the reconnection layer at the dayside magne topause. The result is shown for a case with a zero guide field (B-y = 0) in the magnetosheath and magnetosphere. A quasi-steady reconnectio n layer develops behind a leading transient bulge in the outflow regio n of the reconnection, in which an intermediate shock is present on th e magnetosheath side. The structure of the intermediate shock varies w ith the distance from the X line along the magnetopause. An accelerate d plasma flow is present in the boundary layer on the magnetospheric s ide of the intermediate shock. The ion transport across the magnetopau se boundary layer during the formation of the reconnection layer is al so investigated.