ROSES ID: NNH22ZDA001N-LWS Selection Year: 2022
Program Element: Focused Science Topic
Principal Investigator: Yuxi Chen
Affiliation(s): Princeton University
Project Member(s):
Wang, Liang Co-I Princeton University
Toth, Gabor Co-I University Of Michigan, Ann Arbor
Sun, Weijie Co-I/Institutional PI University Of Michigan, Ann Arbor
Dong, Chuanfei Collaborator Princeton University
Summary:
Magnetic reconnection is widely considered as the most important mechanism for the solar wind plasma transferring into the magnetosphere. The local properties of magnetic reconnection, such as the local reconnection rate and the plasma flow around the reconnection site, have been extensively studied with both local simulations and satellite observations. However, it is difficult to measure the global consequences of the magnetopause reconnection with in situ satellite data, and such investigation largely depends on global numerical simulations. Ideal and resistive MHD models have been widely used to simulate solar wind-magnetosphere coupling. These models usually produce well-defined steady separatrices at the magnetopause, and the global reconnection rate, which is closely related to the efficiency of solar wind plasma transferring into the magnetosphere, can be calculated as the integral of the electric field along a separator line. In recent years, however, both beyond-MHD simulations and satellite data indicate that the magnetopause X-lines are usually patchy and unsteady, and the products of multiple X-line reconnection, flux transfer events (FTEs), occur frequently. Such complex reconnection structures imply the global solar wind-magnetosphere coupling efficiency needs to be revisited. However, it is difficult to apply the electric field integral method to calculate the global reconnection rate for such beyond-MHD simulations, because 1) it is not trivial to find and trace the patchy and unsteady magnetopause X-lines, and 2) it is not clear how the contribution of FTEs should be evaluated. On the other hand, traditional MHD simulations do not contain kinetic phenomena that are produced by the bow shock, and they may have a significant influence on magnetopause reconnection. _x000D_