title: Molecular Origin of Io's Fast Sodium.
abstract: Neutral sodium emissions encircling Jupiter exhibit an intricate and variable structure that is well matched by a simple loss process from Io's atmosphere. These observations imply that fast neutral sodium is created locally in the Io plasma torus, both near Io and as much as 8 hours downstream. Sodium-bearing molecules may be present in Io's upper atmosphere, where they are ionized by the plasma torus and swept downstream. The molecular ions dissociate and dissociatively recombine on a short time scale, releasing neutral fragments into escape trajectories from Jupiter. This theory explains a diverse set of sodium observations, and it implies that molecular reactions (particularly electron impact ionization and dissociation) are important at the top of Io's atmosphere.
authors.forename: N M
authors.initials: NM
authors.lastname: Schneider
authors.forename: J T
authors.initials: JT
authors.lastname: Trauger
authors.forename: J K
authors.initials: JK
authors.lastname: Wilson
authors.forename: D I
authors.initials: DI
authors.lastname: Brown
authors.forename: R W
authors.initials: RW
authors.lastname: Evans
authors.forename: D E
authors.initials: DE
authors.lastname: Shemansky