Magnetopause reconnection under a southward IMF is investigated with our 3-D self-consistent global hybrid simulation model. The magnetic configuration and evolution of Flux Transfer Events (FTEs), the associated ion density and ion velocity distribution at various locations on the magnetopause, and the energy spectra of cusp precipitating ions associated with the reconnection are studied. Multiple X lines are formed during the magnetopause reconnection, which lead to both FTEs and quasi-steady-type reconnection under a steady solar wind condition. The resulting bipolar signature of local normal magnetic field of FTEs is consistent with satellite observations. Flux ropes that lead to FTEs form between X lines of finite lengths and evolve relatively independently. The ion density is enhanced within FTE flux ropes because of the trapped particles, leading to a filamentary global density. Different from the previous understanding, a quadrupole magnetic field signature associated with the Hall effects is found to be present around FTEs. Moreover, a combination of patchy reconnection and multiple X line reconnection leads to the formation of closed field lines from the magnetosphere to the magnetosphere in the magnetopause boundary layer. Finally, both the spatial and temporal energy spectra of cusp precipitating ions are computed by tracing trajectories of the transmitted magnetosheath ions. The spatial spectrum shows a dispersive feature consistent with satellite observations, with higher energy particles at lower latitudes and lower energy particles at higher latitudes. The simulation reveals how and where particles are transmitted from the solar wind into the magnetosphere via direct magnetic reconnection on the dayside.
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