| The quadrupolar pattern of magnetic field component of vertical magnetic reconnection plane (namely 'the vertical field') which is generated by Hall Effect is taken as one of crucial criterion to identify fast reconnection processes. Hall Effect is the motion of electrons and ions decouple when scale lengths are smaller than the ion inertial length, and it is formed Hall currents, then accompanying a characteristic vertical field perturbation present quadrupole pattern. The Hall Effect is the critical factor for the rate of reconnection. Particle in cell (PIC), Hybrid (kinetic ion, fluid electron), Hall-MHD et al. codes are better suitable for fast collisionless reconnection. This thesis uses hybrid model (kinetic ion, no inertial fluid electron) to investigate quadrupolar pattern of vertical field which is generated by Hall Effect when magnetic field perturbation is formed in the presence of different sheared flow of vertical plane. Here we initially add in parallel and perpendicular shear flow which is relatively anti-parallel reconnecting magnetic field. Parallel shear flow is formed magnetic field perturbation possible linearity superimposition with that the Hall effect produces. This weakens the Hall effect, therefore symmetrical bipolar structure about the current become one strong, the other is weak. Or the quadrupolar pattern appear the bipolar structure. Thus observation judgment the fast magnetic reconnection is affected. The magnetic field perturbation which the perpendicular shear flow and the Hall effect produce may be nonlinear evolution. It makes quasi-steady single X line reconnection develop intermittent multiple X line reconnection. |
