Simulations of Electron Interaction With Ionospheric Alfvén Resonator in the Jovian Aurora

Recently, Lysak et al. (2021, https://doi.org/10.1029/2021ja029886 ) modeled the formation of the Ionospheric Alfvén Resonator (IAR) in Jovian aurora and demonstrated the generation of a small structure perpendicular to the magnetic field and a parallel electric field in the low‐density region. This field oscillates on a timescale of about one second, roughly corresponding to the transit time of electrons through this area. Based on these findings, they predicted a broadband acceleration of electrons. In this study, we expand the modeling by incorporating test particle simulations. We divide the simulations into two parts: one focusing on high‐energy electrons (above multi‐keV) of magnetospheric origin and the other on low‐energy electrons (less than approximately 1 keV) of ionospheric origin. For the high‐energy electrons, we demonstrate the formation of a broadband distribution from a mono‐energetic electron distribution. The broadening is seen when the flux is observed at low time resolution, compared to the IAR period. At higher time resolution, the electron flux displays oscillations at the IAR frequency. Additionally, we found that the flux oscillations induced by the IAR at different latitudinal points are out of phase. Furthermore, we show that the integrated flux with energy and solid angle shows longitudinal oscillations due to drift. We demonstrate that for low‐energy electrons, the IAR can generate bidirectional beams below the strong region, and a narrow energy beam above this region. Additionally, we show the formation of beams at discrete energies above the strong region.