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Space Plasma Research at UTA J. L. Horwitz Department of Physics The University of Texas at Arlington UTA Space Plasma Group Dr. J. L. Horwitz, Professor and Department Chair Dr. Wen Zeng, Post-Doctoral Researcher Ms. Fajer Jaafari, Doctoral Graduate Student Cf. also Dr. Yi-Jiun Su, Assistant Professor of Physics Funded by National Science Foundation and NASA Magnetosphere Magnetosphere High-latitude Ionosphere Auroras POLAR/TIDE/UVI observations of ionospheric field-aligned flows and auroral forms at 5000 km Stevenson et al.[2001] employed POLAR Southern perigee observations to elicit relationships of highlatitude O+ field-aligned flows observed by TIDE to auroral forms by UVI. Typically, auroral emissions associated with upflows, dark regions with down-flows. POLAR/TIDE Parallel Flows with Auroral Forms for May 4,1996 It is useful to divide the field-aligned ionospheric flows according to altitude region: F-region/topside up/down flows-->300--1000 km altitude, <1-2 eV, gravitationally-bound, influenced by frictional ion heating, ambipolar electric fields, soft electron precipitation-Te, ionization. Energized ion outflows->1200-3 RE, 10-104 eV, conics, beams, perp. wave heating, parallel E-fields, etc. Dynamic Fluid-Kinetic(DyFK) treatment for ionospheric field-aligned flows Estep et al.[1999] and Wu et al.[1999, 2002] developed a timedependent treatment for treating field-aligned plasma flow, joining a fluid treatment for the ionosphere (120-1100 km) to a GSK treatment for the upper altitude regions(800 km up) Treating effects of soft electron precipitation, transverse ion heating and hot plasma-driven driven potentials, including a “pressure cooker” situation. Wu et al.[1999] POLAR/TIDE-DyFK Comparisons in Cleft Ion Fountain Paradigm[Tu et al., 2005] O+ Field-aligned Velocities • DyFK simulated • Polar/TIDE measured Dy FK /T IDE IMAGE/RPI Electron Densities DyFK-IMAGE/RPI Comparisons: Simulation Convection Trajectories[Tu et al., 2004b] DyFK-IMAGE/RPI-DMSP Profile 3 Comparison [Tu et al., 2004b] DyFK-IMAGE/RPI-DMSP Profile 2 comparison with and without auroral processes [Tu et al., 2004b] Characteristic Ion Distributions in the Dynamic Auroral Transition Region Zeng et al.[2005]