The investigators will build a Fabry-Perot Interferometer (FPI) and install it near the southern crest of the equatorial ionization anomaly (EIA) initially at the Mercedes Observatory (for a ~ 3-6 month campaign observation) and later at El Leoncito Observatory, where additional ionospheric instrumentation already exists. Neutral winds and temperatures are key parameters needed to understand upper atmosphere processes. Most of our knowledge of neutral parameters in the upper atmosphere comes from observations obtained by FPIs. The measurement of winds and temperatures at ~250-300 km and at ~95 km will be combined with other parameters obtained with co-located optical and ionosonde instrumentation. The main objective of the study is to improve understanding of ion-neutral coupling processes in the region. Different experiments will be carried out, e.g., the latitudinal comparison of neutral winds using other FPIs, the comparison of zonal winds and zonal plasma drifts (inferred from the motion of airglow depletions), and the study of high latitude midnight temperature maximum (MTM) effects. The study will also contribute to research on the dynamics and electrodynamics of the upper atmosphere. The effort includes the organization of a mini-workshop on multi-instrument studies of the upper atmosphere to foster the collaboration between U.S. and Argentine researchers.
