Electron density distribution in the plasmasphere in conjunction with IRI model, deduced from Akebono wave data

Determination of electron density distribution in the plasmasphere has been attempted using wave normal directions and delay time of Omega signals, and in-situ electron density observed on the Akebono satellite /1/, /2/. The present study is based on the assumption that the plasma model is represented by a diffusive equilibrium (DE) model with a vertical temperature gradient, and the electron density at a reference altitude (1000km) being dependent on the L value. The parameters related to these models were determined by non-linear least square fitting of the in-situ electron density, the wave normal direction and delay time of Omega signals observed by Akebono. Relative concentrations of ion constituents of H + , He + , O + at the reference altitude are determined by fitting as either L independent or L dependent. Connecting the global plasmaspheric density model with IRI in the ionospheric altitude is also tried.