Computer Simulations on the Fast Reconnection Mechanism

The basic physics of the fast reconnection mechanism is studied by computer simulations. The present paper extends the coplanar spontaneous fast reconnection model to the general sheared field geometry. We find that, even in a sheared field geometry with no magnetic neutral (or null) point, the magnetic field lines of different polarities are cut and connected to one another at the origin through the reconnection process. Once the fast reconnection mechanism builds up, it in fact causes the drastic topological change (or magnetic flux transfer) even in a sheared field. It is also found that the thin (shock) transition layer, associated with the fast reconnection mechanism, is divided into the intermediate wave region and the slow shock region. In the intermediate wave region, a pure finite-amplitude intermediate wave stands almost steadily, where magnetic field simply rotates without changing its magnitude. In the slow shock region, a slow shock is combined with a fin! ite amplitude intermediate wave.