A Kinetic Model of the Ionospheric Return Currents

We present a 1D kinetic model of the collisional low altitude auroral ionosphere: the electrons drift through a gas composed of ions and neutrals under the influence of a parallel electric field. We take into account electron/ion (e/i) and electron/electron (e/e) collisions. A Monte‐Carlo method is used to simulate with the electron/neutral (e/n) collisions. In order to take into account the temporal evolution, we introduce a feedback on the electric field. We impose a current density and calculate the corresponding electric field. The current density is divergence free. We show that the Electron Distribution Functions (EDF) are non Maxwellian. We calculate an effective conductivity that takes into account the kinetic effects. The modelled conductivity is larger by 30% than the classical one. This work reveals the importance of kinetic models and gives access to the conductivity profile, which are useful to study the ionospheric currents.