Understanding the Dynamics of the Coupled Ring Current Radiation Belt System Using 4D VERB Simulations

Monday, 15 December 2014: 4:54 PM
Yuri Shprits1,2, Adam C Kellerman2, Alexander Drozdov2, Ksenia Orlova2 and Maria Spasojevic3, (1)Massachusetts Institute of Technology, Cambridge, MA, United States, (2)University of California Los Angeles, EPSS, Los Angeles, CA, United States, (3)Stanford University, Stanford, CA, United States
Predicting and understanding the non-linear response of different electron populations in the inner magnetosphere, including ring current and higher energy radiation belts, has been a grand challenge since the beginning of the space age. During this past decade, there have been a number of long-term simulations that used lower energy boundary condition observations around geosynchronous orbit. In this study, we set up observations at around 15 RE and study how the combined convective-diffusive transport can result in the acceleration of keV to relativistic and ultra-relativistic energies. We show that while lower energy radial transport is dominated by the convection, higher energy transport is dominated by the diffusive radial transport. MLT dependent diffusion confidents allow us to study how difference in wave properties at different MLT can influence the dynamics of the particles. Inclusion of adiabatic changes also allows us to study the radial transport that results from pitch-angle scattering and adiabatic changes. We also show that there exists an intermediate range of energies for electrons for which both processes work simultaneously. We show the comparison of the 4D VERB simulations with the Van Allen Probes measurements.