Two-Dimensional Phenomenological Model of Ring Current Dynamics in the Earth’s Magnetosphere

Abstract

The dynamics of ring current protons with variable boundary conditions in the inner magnetosphere during a magnetic storm has been studied. The spatial and temporal evolution of differential fluxes of protons in the dipole magnetic field has been calculated. The calculations have been performed with the two-dimensional Phenomenological Model of the Ring Current (PheMRC 2-D) offered by the author, which examines the radial and pitch angle diffusions with consideration of losses due to wave–particle interactions. The simulation begins with the distribution of magnetically quiet time. The model has been tested via comparison of the calculated proton fluxes with values measured on the Polar/MICS satellite during the magnetic storm on October 21–22, 1999. The calculated pitch angle distribution is quite consistent (well) with the experimental data. The model has been compared with the other ring current model (Extended Comprehensive Ring Current Model, ECRCM) (Ebihara et al., 2008). PheMRC 2-D is more accurate than ECRCM in describing the experimental data. The offered model can be used to simulate the dynamics of charged particles in the Jovian and Saturn magnetospheres.