SM31C-2525
The Relative Proportions of Water Group Ions in Saturn's Inner Magnetosphere: A Preliminary Study
Wednesday, 16 December 2015
Poster Hall (Moscone South)
Robert J Wilson1, Fran Bagenal2, Tim Cassidy1, Bobby Fleshman3 and Frank J Crary2, (1)University of Colorado Boulder, Boulder, CO, United States, (2)University of Colorado at Boulder, Boulder, CO, United States, (3)Lawrence University, Appleton, WI, United States
Abstract:
We present a technique to gather ion composition information in the form of relative abundances of the water group ion species in Saturn's inner magnetosphere, utilizing the Cassini Plasma Spectrometer's Straight-Through Time-of-Flight data from two orbits in 2011. We show that between 4.75 and 8 Saturn radii H2O+ ions dominate the water group species, and from 8 to 10 Saturn radii it is OH+ ions that dominate. Our results show that the relative proportion of H3O+ falls fastest with increasing distance, while the proportion of H2O+ decreases slowly. However O+ and OH+ increase with distance and O+ is the least dominant ion species out to 8 Saturn radii outside of which it is comparable to H3O+. The relative abundance of H2O+ found here matches theoretical work based on Herschel telescopic data very well. These results are compared with other published work and further improvements to the technique are discussed.
