In Situ Analysis of Jupiter's Broadband Kilometric Auroral Radio Emissions With Juno

Among the zoo of Jovian auroral radio emissions, the broadband kilometric (bKOM) component has been the least studied. Taking advantage of Juno in situ measurements within the auroral regions, we surveyed the Juno/Waves radio observations over the 60 first orbits to identify 7 bKOM source candidates. These were mostly detected during dawn storm auroral episodes (4/7) and three were found to be colocated with auroral cavities. By applying a growth rate analysis based on JADE-E electron measurements, we show that the observed waves are driven by the Cyclotron Maser Instability from two free energy sources. The main emission, produced slightly above the electron gyrofrequency $\left(f_{ce}\right)$, is amplified by conics-type electron distribution functions (EDF) with 2–30 keV electron characteristic energies. Sporadic bursts, produced slightly below $f_{ce}$, are driven by shell-type EDF of 0.1–10 keV. These results are analyzed comparatively to those obtained previously for Jovian hectometric and decametric emissions.