An empirical model of oxygen charge state distributions in the Earth's magnetosphere

Oxygen ions within the magnetosphere of Earth originate from two sources: the ionosphere and the solar wind. The sources of this plasma can be determined from the charge state of the ions. Ionospheric-originating ions will have low charge states (i.e., O+ and O2+), whereas solar wind-originating ions will have high charge states (i.e., O6+). The distributions of these ions have previously been explored using observations from CAMMICE/MICS onboard Polar. In this study we characterize these prior observations via an empirical model of oxygen charge state distributions in the magnetosphere of Earth for variations in Kp, Vsw Bz, and AE in both L-shell and magnetic local time. Model results are also compared to previously published oxygen charge state distributions observed by Polar, GEOS, and AMPTE/CCE.