Evidence of Electron Energisation by Alfvenic Turbulence
Abstract
Prior to the arrival of Juno, it was largely believed that immense field-aligned potentials were the energisation mechanism responsible for producing Jupiters powerful auroral display. Now, it is becoming increasingly evident that an amalgamation of processes is likely to be providing the energy needed for the observed auroral intensity. One such process is wave-particle interactions. Whilst a relatively lesser energisation mechanism at Earth, wave-particle interactions are now believed to be one of the dominant particle acceleration mechanisms in the Jovian magnetosphere. The Juno mission provides a unique opportunity to investigate this form of energisation thanks to its elliptical polar trajectory, passing through a range of magnetic latitudes at varying radial distances. We utilise the 64Hz vector magnetometer in conjunction with high resolution observations from the electron plasma instrument, JADE, to investigate the energisation mechanism arising from the ubiquitous presence of Alfvén waves within the system. Our findings suggest the presence of transient Alfvénic turbulence in the mid-to-high latitude regions of the Jovian magnetosphere. These events exhibit turbulent cascades with spectral indices corresponding to energy dissipation at the electron inertial scale. The associated energy flux of the turbulent events is sufficient to energise electrons to the observed energies required to generate auroral emissions.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2021
- Bibcode:
- 2021AGUFMSM45G..01L