Energy Dissipation and Transport Associated with Whistler-wave Generation during Plasma Jet Events using MMS Data
Résumé
Plasma jets aka bursty bulk flows play a crucial role in Earth's magnetosphere dynamics, in particular during substorms where they can penetrate down to the geosynchronous orbit. The energy input from the solar wind is partly dissipated in jet fronts (also called dipolarization fronts) in the form of strong whistler waves that can heat and accelerate energetic electrons. The ratio of the energy transported during jets to the substorm energy consumption can reach one third or more due to kinetic-scale phenomena, that are still under debate due to instrumental limitations. The recently-launched Magnetospheric Multiscale (MMS) mission has already detected numerous plasma jet events, and evolves in a tetrahedral configuration (with an average inter- satellite distance of 160 km and unprecedent resolutions up to 16,000 samples/s) that allows to study in detail the microphysics of these phenomena. Thus in this study we employ MMS data to investigate the energy dissipated in jet fronts related to the generation of whistler waves, and the interaction of such waves with energetic electrons in the vicinity of the flow/jet braking region near the equatorial boundary between tail and inner magnetosphere. We also make use of ray tracing simulations to evaluate their propagation properties, as well as their impact on particles in the off-equatorial magnetosphere.