A new global physical model of the electron radiation belts of Jupiter inside the orbit of Europa is presented. It is an update of the Office National d'Etudes et de Recherches Aérospatiales model Salammbô proposed by Sicard and Bourdarie () that now integrates a contribution of the wave‐particle interaction above the orbit of Io. In addition, a revisited and more realistic boundary condition near Europa is implemented. The new Salammbô model is validated against the in situ flux measurements obtained by the Pioneer 10, Pioneer 11, and Voyager 1 missions. The role of the wave‐particle interaction is discussed by investigating its effect on the predicted in situ fluxes. In particular, the interaction appears in our simulations as a strong pitch angle scattering process explaining the flux depletions intensities near the orbit of Io as well as the flux intensities near the spacecraft perijoves.

A physical model of the Jovian trapped protons with kinetic energies higher than 1 MeV inward of the orbit of the icy moon Europa is presented. The model, named Salammbô, takes into account the radial diffusion process, the absorption effect of the Jovian moons, and the Coulomb collisions and charge exchanges with the cold plasma and neutral populations of the inner Jovian magnetosphere. Preliminary modeling of the wave-particle interaction with electromagnetic ion cyclotron waves near the moon Io is also performed. Salammbô is validated against in situ proton measurements of Pioneer 10, Pioneer 11, Voyager 1, Galileo Probe, and Galileo Orbiter. A prominent feature of the MeV proton intensity distribution in the modeled area is the 2 orders of magnitude flux depletion observed in MeV measurements near the orbit of Io. Our simulations reveal that this is not due to direct interactions with the moon or its neutral environment but results from scattering of the protons by electromagnetic ion cyclotron waves.

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Imaging of energetic neutral atoms coming from a trans‐Europa region and energetic proton observations by Galileo around Jupiter have previously revealed the existence of a neutral gas torus produced by Europa. Energetic sulfur ions observed by Galileo do not show any effect of the Europa torus for Mc Ilwain parameters L > 9.2, surely because ions are multiply charged, so that the torus first needs to bring the ions charge state to one before being able to neutralize them. Signatures of the Europa torus in energetic sulfur ion measurements obtained near the magnetic equator at L = 9.08–9.20 during Galileo orbits C10 and E11 are reported for the first time in this letter. They provide an independent confirmation of the Europa neutral gas torus. Pitch angle distributions suggest that protons might principally interact with a vertically thin neutral oxygen torus, while sulfur ions are lost by charge exchange with a vertically thicker hydrogen torus.