The proton concentration in the vicinity of the Io plasma torus

Observations of lightning-generated whistlers conducted with the aid of the Voyager 1 plasma wave instrument during the March, 1979 encounter of Jupiter have been employed in numerous studies involving Jupiters's inner magnetosphere. In an investigation carried out by Tokar et al. (1982), the Voyager whistler observations were combined with heavy ion charged particle measurements in the Io torus to determine the light ion charge concentration along the whistler propagation paths. In the investigation, simple models were used for the plasma distribution along the propagation paths. In the present study, an improved model is used for the plasma distribution in the inner magnetosphere. The adopted model treats a plasma in diffusive equilibrium under the action of gravitational, centrifugal, and ambipolar electric field forces.