Filamentation of Tail Current Sheet as seen Through High Resolution Global Multi-Fluid Simulations

Particle models of the tail current sheet often show the presence of very thin structures. However, placing such dynamics into the global context has been difficult because the limited region that can be incorporated in particle models. Conversely, global models typically have a grid resolution too course to resolve such features and neglect the key physical processes relevant to thin current sheets. These limitations are addressed in the multi-fluid model which includes ion cyclotron effects in the fluid limit (i.e. no high energy particle tails are included) with refinement gridding now incorporated. The refinement gridding allows resolution down to 400 km while enabling a full global treatment of mass and energy transport throughout the magnetosphere. At this resolution, thin current sheets can be resolved and shown to be highly structured/filamented as opposed to classical course resolution cartoon of the magnetosphere. This filamentation leads to the interaction between various neutral lines through the plasma flows that they generate. An observable feature that is not seen in ideal MHD is the generation of earthward as well as tailward moving flux ropes. Such flux ropes have been seen in Geotail data.