Modeling of Saturn’s radiation environment

A common problem in space physics is how the energetic particles we observe in space are accelerated to high energies. In the magnetospheres and radiation belts of magnetized planets like the Earth and Saturn, we find electrons with up to MeV energies. There are two fundamental acceleration processes. Electrons can gain energy when they are transported closer to the planet (radial acceleration), where the magnetic field is stronger. The alternative is that the electrons are accelerated locally, through fluctuating electric or magnetic fields and wave-particle interaction. In this work, we use a modified version of the Versatile Electron Radiation Belts code to perform the simulations of the radiation belts at Saturn. Using convection terms of a modified Fokker-Planck equation, the zebra stripes and banana orbit signature is reproduced in the convection-diffusion code. Using the flexibility of our simulation framework, we explore the effects of radial diffusion, coulomb scattering and the local diffusion. Throughout the series of simulations, we aim to understand the role of the controlling processes of the radial transport acceleration (e.g., due to variable electric field) and the role of local acceleration, as well as any other processes needed to reproduce the observations.