Simulation Study of Small-scale Plasma / Neutral Dynamics during Poleward Moving Auroral Forms

Poleward Moving Auroral Forms (PMAF's) sweep multiple bands of electron precipitation through cusp region locations. Soft electron precipitation alone is known to initiate a range of plasma reactions, such as increased temperature, density, ion upwelling and possibly neutral upwelling. The timescales of these reactions vary from a few seconds (electrons) to 10s of seconds (ion upwelling) to 10s of minutes (plasma density and neutral upwelling). Poleward Moving Auroral Forms introduce a cyclic dynamic to these complex reactions where several minutes of intense electron precipitation are followed by several minutes of reduced intensity. We investigate the small-scale dynamics of PMAF's using a kilometer-scale, three-fluid, ionosphere-thermosphere numerical model which includes inertial ion and neutral terms. Soft electron precipitation input alternates between high- and low-flux values, simulating one or more PMAF band sweeping through the spatial region. Simulation results are presented which detail the temporal evolution of plasma and neutral populations to this cyclic input over a range of electron precipitation energies.