Whistler Mode Waves Associated With Broadband Auroral Electron Precipitation at Jupiter

Large amplitude electromagnetic plasma waves are observed simultaneously with intense fluxes of electrons precipitating on auroral field lines at Jupiter. Here we present plasma wave observations from the Juno Waves instrument obtained during an instance of very intense broadband electron precipitation observed by the Jupiter Energetic Particle Detector Instrument connecting to Jupiter's main auroral oval. The wave spectrum extends from 50 Hz to similar to 10 kHz with peak-to-peak amplitudes of similar to 10 nT in the magnetic channel and of similar to 1 V/m in the electric channel, representing some of the most intense plasma waves observed by Juno. The E and B fields of these electromagnetic waves are correlated and have apparent polarization perpendicular to Jupiter's magnetic field with a downward Poynting flux. We conclude the plasma waves are whistler mode emissions with a possible admixture of ion-cyclotron or Alfven waves and may be important in the broadband electron acceleration. Plain Language Summary Large amplitude whistler mode waves are found coincidently with intense fluxes of precipitating electrons across a broad energy range connecting to Jupiter's main auroral oval. The whistler mode waves are propagating downward, in the same direction as the precipitating electrons. The tight correspondence in time between the waves and the electrons strongly suggests an important interaction between the waves and electrons.