"Matreshka" model of multilayered current sheet.

International audienceCurrent sheets are one of the key elements of the Earth's magnetosphere, determining the magnetic energy storage and release. An analytical self-consistent model of multicomponent thin current sheets, where the plasma consists of ions of both solar wind and ionospheric origin, is presented. The influence of the electron population is taken into account assuming Boltzman-like quasi-equilibrium distribution in the electrostatic field, which can lead to a sharp peak in the electron current density in the center of the current sheet. We include the contribution of non-adiabatic O+ ions in our model as one of the terms in the Grad–Shafranov-like system of equations describing the quasi-equilibrium configuration. The contribution of the oxygen ions to the total cross-tail current usually does not exceed 30% for realistic conditions, but current “wings” carried by O+ ions produce significant broadening of the current profil