Evidence of the Alfvén Transition Layer and Particle Precipitation in the Cusp Region: 3D Global PIC Simulation of the Solar Wind–Earth Magnetosphere Interaction

Abstract A transition layer, named the Alfvénic layer (or ATL), has been clearly evidenced near outer boundary of cusp by experimental observations from Cluster mission. This characterized a local value Log M ∼ 1, where is Alfvén Mach number, allows bulk flow to transit super-Alfvénic sub-Alfvénic exterior interior side cusp. The ATL observed during northward interplanetary magnetic field orientation, and mainly within meridian plane. Currently, 3D Particle In Cell (PIC) global simulations solar wind–magnetosphere interaction are being performed in order analyze region this detail. Present results stress following points: (i) structure; (ii) plane, appears as sublayer much more extended slow-mode pattern, it almost adjacent located above upper edge stagnant (SEC); (iii) plasma deceleration through not uniform addition, present preliminary that (a) spiraled streamlines ion/electron fluxes converge when approaching cusp, their intensity strongly increases; (b) ion electron energetic penetrating differ terms penetration depths issued different regions magnetosphere/magnetosheath. Our illustrate importance effects used with PIC simulation approach allowing analysis each population simultaneously.