Injections of Multi‐MeV Electrons in the Magnetosphere of Jupiter

Abstract Energetic particle injections provide a means for fast inward radial transport and adiabatic acceleration of electrons in the magnetosphere of Jupiter. Furthermore, enhanced whistler‐mode wave activity during injections can further accelerate electrons to MeV energy. All in all, injections may contribute to the creation of the most extreme radiation belts of the solar system. In this article, we present the first survey of the >1 and >11 MeV electron fluxes observed by the Galileo mission during <1 MeV electron injections. We find that the flux of MeV electrons remains nearly unchanged during most of the sub‐MeV electron injections, possibly because the MeV particles quickly drift out of the injection corridor. Nevertheless, we report the discovery of six time periods at M = 11–20 when the flux of MeV electrons is increased by a factor of more than 3 during injection events. The Galileo observations therefore indicate that magnetospheric injections may play a dominant role for the radial transport and acceleration of MeV electrons at Jupiter, at least transiently.