Temporal Evolution of Electron Precipitation-Driven Ion Upwelling and Coupling to Neutral Particles

CHAMP satellite observations have confirmed neutral density enhancements which are localized to the high latitude polar cusp region. These small-scale density structures are consistently correlated with strong fine-scale field-aligned currents. A possible driver of these density enhancements is soft electron precipitation which, through processes associated with ion-outflow, results in a density enhancement in the cusp vicinity at the altitudes observed by CHAMP. We investigate this mechanism on two fronts: with a numerical model capable of fine-scale resolution (spatial and temporal) of plasma / neutral populations, and with in-situ data measurements. Results are presented which detail the temporal evolution of electron precipitation driven ion upwelling; comparisons of other published temporal evolution results are shown. In addition, e-POP instrumentation and orbit characteristics are highlighted which will shed light on this possible driver of neutral density enhancements.