Investigating Energy-Dependent Dynamics of Inner Magnetosphere Particles Using the CIMI Model and Satellite Observations

There are three major plasma populations reside in the inner magnetosphere: the plasmasphere ( 1 eV), the ring current ( 1 - 500 keV) and the radiation belts (> 500 keV). The large-scale transport of these plasma populations largely depends on their energies. The drift of low-energy (< 50 keV) particles are dominated by convection, while high-energy (> 500 keV) particles are mainly controlled by magnetic drift. Both convection and magnetic drift are important for particles with transition energies. Not only is macro-scale transport energy-dependent, micro-physical effects depend on energy as well. For instance, an important loss process of electrons with energies less than 50 keV is pitch-angle scattering by interaction with whistler mode chorus waves. On the other hand, the same wave mode can accelerate electrons with energies higher than 500 keV. The seed population for this acceleration process also depends on large-scale transport of source population from the plasma sheet. To understand these cross-energy, cross-scale couplings, analysis of data from various instruments together with a global model that covers a wide range of energy and considers both macro- and micro-physics is essential. In this paper, we will show how the storm-time dynamics of the radiation belts can be explained by cross-energy and cross-scale couplings.