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Interchange instability is known to drive fast radial transport of particles in Jupiter's inner magnetosphere. Magnetic flux tubes associated with the interchange instability often coincide with changes in particle distributions and plasma waves, but further investigations are required to understand their detailed characteristics. We analyze representative interchange events observed by Juno, which exhibit intriguing features of particle distributions and plasma waves, including Z‐mode and whistler‐mode waves. These events occurred at an equatorial radial distance of ∼9 Jovian radii on the nightside, with Z‐mode waves observed at mid‐latitude and whistler‐mode waves near the equator. We calculate the linear growth rate of whistler‐mode and Z‐mode waves based on the observed plasma parameters and electron distributions and find that both waves can be locally generated within the interchanged flux tube. Our findings are important for understanding particle transport and generation of plasma waves in the magnetospheres of Jupiter and other planetary systems. 

We report some of the most intense Z‐mode and O‐mode observations obtained by the Juno spacecraft while in orbit about Jupiter in a low to mid‐latitude region near the inner edge of the Io torus. We have been able to estimate the density of the plasma in this region based on the lower frequency cutoff of the observed Z‐mode emission. The results are compatible with the electron density measurements of the Jovian Auroral Distributions Experiment (JADE), on board the Juno spacecraft, if we account for unmeasured cold plasma. Direction‐finding measurements indicate that the Z‐ and O‐mode emission have distinct source regions. We have also used the measured phase space density of the JADE and the Jupiter energetic particle detector instruments to calculate estimated local growth rates of the observed O‐mode and Z‐mode emission assuming a loss cone instability and quasilinear analysis. The results suggest the emissions were observed near, but not within, a source region, and the free energy source is consistent with a loss cone. We have thus carried out the quasilinear wave analysis of the assumed remote Z‐ and O‐mode wave growths. It is shown that the remotely generated waves, propagated through an inhomogeneous medium to the satellite location, may account for the observed wave characteristics. The importance of Z‐mode in accelerating electrons in the inner Jovian magnetosphere makes these new wave mode confirmations at Jupiter of particular interest. 

We present the average distribution of energetic electrons in Jupiter's plasma sheet and outer radiation belt near the magnetic equator during Juno's first 29 orbits. Juno observed a clear decrease of magnetic field amplitude and enhancement of energetic electron fluxes over 0.1–1,000 keV energies when traveling through the plasma sheet. In the radiation belts, Juno observed pancake‐shaped electron distributions with high fluxes at ∼90° pitch angle and whistler‐mode waves. Our survey indicates that the statistical electron flux at each energy tends to increase fromto. The equatorial pitch angle distributions are isotropic or field‐aligned in the plasma sheet and gradually become pancake‐shaped at. The electron phase space density gradients atMeV/G are relatively small atand become positive over, suggesting the dominant role of adiabatic radial transport at highershells, and the possible loss processes at lowershells.