Studying the dynamics of Mercury's magnetotail with the MHD-EPIC model

Mercury's magnetosphere is much more dynamic than other planetary magnetospheres because of Mercury's weak intrinsic magnetic field and its proximity to the Sun. Magnetic reconnection and Kelvin-Helmholtz phenomena occur in Mercury's magnetopause and magnetotail at higher frequencies than in other planetary magnetosphere. For instance, flux ropes in the magnetotail have been frequently observed by the the MErcury Surface, Space ENvironment, GEochemistry and Ranging (MESSENGER) spacecraft (Slavin et al., 2009). Because the ion Larmor radius is comparable to typical spatial scales in Mercury's magnetosphere, finite Larmor radius effects need to be accounted for. In addition, it is important to take into account non-ideal dissipation mechanisms to accurately describe magnetic reconnection. In this work, we apply the two-way coupled MHD with embedded PIC (MHD-EPIC) model to study Mercury's magnetosphere. The magnetotail reconnection region is covered by the PIC code. We are going to discuss the evolution of the flux ropes, and compare the simulation result with MESSENGER observations. The dawn-dusk asymmetry of the reconnection signatures in Mercury's magnetotail is also studied.