Interaction of magnetosheath reconnection with magnetopause reconnection driven by interplanetary tangential discontinuity: A three-dimensional global hybrid simulation with Oblique IMF

Terrestrial dayside dynamics associated with a northward turning interplanetary magnetic field (IMF) carried by an interplanetary tangential discontinuity (TD) is investigated by performing a three-dimensional (3D) global-scale hybrid simulation. Results of several runs are presented, in which the initial unperturbed IMF is southward and in the GSE plane, and the incoming TD possesses various magnetic field rotation angle () and half-widths. Magnetopause flux ropes/FTEs are formed under the southward IMF on the earthward side of the transmitted TD in the magnetosheath, and then magnetosheath reconnection is found downstream of both the quasi-parallel (Q-||) and quasi-perpendicular (Q-) shocks due to interaction of the directional TD with the bow shock and magnetopause. Downstream of the Q- shocks, longer magnetosheath flux ropes are generated under a thinner half-width and larger of the TD. There exists a dawn-dusk asymmetry in the spatial extent of the magnetosheath flux ropes, which becomes more significant as decreases. When is less than , no reconnection flux ropes appear in the magnetosheath. The magnetosheath reconnected flux ropes are also found in the transmitted TD downstream of the Q-|| shock. Magnetic re-reconnection is initiated due to the interaction between the magnetosheath flux ropes and the magnetopause. The magnetopause flux ropes can be mixed with the magnetosheath ones. Our simulation also demonstrates that magnetopause reconnection has strong effects on the formation and structure of the magnetosheath flux ropes. The results are compared with our pervious simulations of cases in which the IMF turns from northward to southward across the TD.