Quiet time plasma pressure distribution in the Earth's magnetospheric trap calculated on the basis of the existing models of trapped radiation

One of the main parameters, which control the generation of currents and electric fields in the magnetospheric trap, is the plasma pressure. At present the complete picture of the plasma pressure distribution in the magnetospheric trap has not been obtained yet. Trapped particles of the radiation belts provide a considerable part of plasma pressure at low L-shells. The evaluations of this part during quiet times can be made on the basis of existing trapped radiation models. The radial profiles of plasma pressure at 1.2<L<7 were obtained using the trapped radiation model AP8 MAX (L<6.6) and the theoretical model of the distribution of the proton fluxes in the Earth's radiation belts (L<7) developed on the basis of the numerical solution of the radial diffusion equation with dissipation processes. The calculations were compared with AMPTE/CCE data. It was shown that they are in good agreement at low L-shells. The magnetic field produced by such pressure profiles is analyzed. During the magnetospheric disturbances only the outer part of this pressure distribution is changed. The observed magnetic field disturbance is a result of the difference between the disturbed and quiet-time plasma pressure profiles. The role of geomagnetically effective eastward ring current existing near the inner edge of the plasma sheet is analyzed