Variations of oxygen charge state abundances in the global magnetosphere, as observed by Polar

Abstract Geomagnetically trapped oxygen ions of solar and ionospheric origin have previously been observed in the Earth's magnetosphere. Early observations from Active Magnetospheric Particle Tracer Explorers/CCE have studied this distribution within a limited spatial range of L shells over all magnetic local times (MLT). This study expands on these early results using observations from the Polar spacecraft. The distributions by charge state show O 6+ , from the solar wind, charge exchanging into O 5+ , O 4+ , and O 3+ as the ion populations drift to lower L shells. Meanwhile, ionospheric O + and O 2+ are primarily seen at low L shells and may also play a role in O 3+ populations. We also present here the Dst , V sw ∗ B z , and A E dependencies of oxygen charge states (O + through O 6+ ) in MLT and L shell in the magnetosphere of the Earth. The distributions of these charge states provide insight into the injection and energization of both ionospheric oxygen as well as solar wind ions inside the magnetosphere.