Analysis and modeling of ion-neutral coupling in small-scale auroral structures within the ionosphere

Local-scale models of the auroral ionosphere rely on input specifications for electromagnetic, energetic charged particles and neutral-dynamical quantities in order to accurately represent plasma behavior. In this study we use the GEMINI ionospheric modeling suite to investigate ion-neutral coupling in small-scale auroral structures, focusing on a two-month period with the Swarm satellite conjunctions near the Poker Flat Incoherent Scatter Radar system (PFISR) and colocated optical measurements with the all-sky camera (DASC) and scanning doppler imager (SDI). The study leverages a nightly conjunction of the Swarm A and C satellites (and occasionally B as well) coordinated with ground-based data, of which there are a handful of distinct auroral events (mid-February to late March 2023). Data sets such as these are near-ideal for constructing inputs for the model to simulate the measured active aurora from each respective night. These inputs include the electric field, ion temperature, neutral particle temperature, flux, intensity, electron density, and drift velocity. New scripts within the GEMINI suite are developed to allow for processing of conjunction data inputs (or data from similar experiments) to enable data interpolation, data smoothing, model grid definition, file configuration and processing, and data output for user analysis. Alongside these tools, we run a number of GEMINI auroral simulations to look at momentum and energy transfer into the neutral atmosphere. Analyzing a data set of this nature will help us to further understand the dynamics of the small-scale aurora with the ion-neutral winds and how they can be better incorporated into modeling for inclusivity of variability in factors such as ionospheric density and temperature structure, instabilities of the ionospheric plasma, and the overall behavior of the ionosphere.