Energy flux and characteristic energy of electrons over Jupiter's main auroral emission

Jupiter's powerful aurorae are caused by energetic electrons precipitating from the magnetosphere into the atmosphere where they excite the molecular hydrogen. These electrons are characterized over the auroral regions by the Jovian Auroral Distributions Experiment (JADE) and the Jupiter Energetic particle Detector Instrument (JEDI) on Juno. Derived energy spectra and pitch angle distributions help us understand how these aurorae are created and powered. Corresponding ultraviolet emissions from reconstructed images taken by the Ultraviolet Spectrograph (UVS) on Juno give us the context and allow us to match the electron observations with their impact on the atmosphere. In this study, we show how the electron energy flux and characteristic energy vary from the polar region, over the main emission, and equatorward of the main emission in relationship with the UV emissions. We focus on the closest passes which range from 1.25 to 2 RJ. We find that while the >30 keV electrons dominate the energy flux in the polar regions and equatorward of the main emission, there is a region near the maximum UV brightness where: i) the characteristic energy decreases from more than 100 keV to less than 10 keV and ii) the maximum contribution to, or a significant fraction of, the total downward energy flux comes from <30 keV electrons. This pattern is present in all eight perijove passes for which JADE and JEDI have the best pitch angle coverage. <P />