Speaker
Description
Io losses ~ 1 ton/sec of neutral material through the interaction of the plasma of the torus and its atmosphere.
This canonical loss rate is based on estimates of the ion supply to the torus provided by electron impact ionization of neutrals and is used as a source rate for the simulations of the large neutral clouds (S and O) extending along Io’s orbit.
But the actual processes causing the ejection of these neutrals are poorly understood and rarely addressed by numerical simulations.
We estimate Io’s SO2 neutral loss from two important processes: 1) the resonant charge exchange of SO2+ ions in the atmosphere and corona of Io and 2) the dissociative recombination of SO2+ ions in Io’s dense wake.
We combine an MHD simulation of the plasma flow in Io’s atmosphere with a multi-species chemistry calculation of the reaction rates to estimate Io’s neutral loss rate.
