Plasma properties from Io’s to Europa’s orbit derived from the Hisaki’s EUV observation

Jupiter’s magnetosphere is characterized by its rapidly rotating, powerful magnetic field and plasma originating from its moons. Sulfur and oxygen ions generated from Io spread to Europa’s orbit as a doughnut-shaped Io plasma torus. However, comprehensive observation from Io’s orbit to Europa’s orbit remains limited, leaving the response of plasma properties across this region to Io’s volcanic activity unresolved. In this study, we analyzed the Hisaki/EXCEED data and obtained spectra from Io’s to Europa’s orbit before and after the volcanic event in 2015. From the emission lines, we derived the radial distributions of electron density, temperature, and ion composition. By combining the observation results with a radial diffusion model, we discuss the radial transport of the plasmas associated with Io’s volcanic activity. Written by MATSUSHITA Natsuko.