Multiscale Particle-in-Cell Simulations of the Interaction of the Solar Wind with the Dayside Magnetospheric Boundary

Abstract:

Understanding how magnetic energy is transported and converted into kinetic and thermal energy during the interaction of the solar wind with the dayside magnetospheric boundary has been a challenging problem. This is because it is a complex multi-scale process. Studies of the energy transport must follow both the evolution of the large-scale interaction and the details of the kinetic processes that enable that transport in localized regions. To approach this problem, we have carried out 2-½ dimensional particle-in-cell (PIC) simulations for southward interplanetary magnetic field conditions. The extensive domain (7R_E x 8R_E) used in the simulations allows us to include large-scale features of the solar wind interaction with the geomagnetic field (e.g., curvature and plasma asymmetries at the magnetospheric boundary) while also resolving local kinetic processes such as those occurring at the bow shock and the magnetopause. The computing challenge is addressed by using the results of global magnetohydrodynamic (MHD) simulations to provide initial and boundary conditions for a two-dimensional version of the implicit iPic3d simulation code. We discuss the PIC simulation results in the context of the initial steady MHD state and spacecraft observations to highlight the effects of kinetic processes. In particular, we correlate particle distributions with the wave activity occurring in different regions of the simulations to assess the effects of wave-particle interactions on the transport through the bow shock-magnetosheath-magnetopause system.