HR: 11:50h
AN: SM42A-07    [Abstracts]
TI: Further Advances in Formula Representation of High-Latitude O+ Ionospheric Outflows Based on DyFK Simulations
AU: * Horwitz, J L
EM: horwitz@uta.edu
AF: Department of Physics, The University of Texas at Arlington, Arlington, TX 76019, United States
AU: Zeng, W
EM: zengw@uta.edu
AF: Department of Physics, The University of Texas at Arlington, Arlington, TX 76019, United States
AB: Considerable interest exists in the magnetospheric community in obtaining compact representations of the ionospheric outflow fluxes and their relationships to putative drivers. Recent satellite data analyses by Strangeway et al.[2005] and Zheng et al.[2005] have obtained formula fits for the measurement-based relationships of the outflows levels to parameterizations for electron precipitation and Poynting fluxes, which are expected to be among the principal drivers, or closely related to them, for the ionospheric outflows. In this presentation, we shall use the results of an extensive set of systematic simulation runs with our Dynamic Fluid Kinetic (DyFK) simulation code for ionospheric plasma field-aligned transport to obtain O⁺ outflow flux levels versus precipitation electron energy flux levels, characteristic energy levels of the precipitating electron, and the peak spectral wave densities for BBELF waves which transversely heat ionospheric ions, and other geophysical conditions. We shall present spectrograms of the relationship of the ion outflow values to these electron energy flux and BBELF wave levels. A preliminary approximate formula representation at this time is: Flux_O+ = 3.03*(3.0x10⁵ + 0.02x10⁹ f_e^1.4)(tanh(8D_wave)+0.2D_wave^0.6)*exp([500- En]/390)^2.6 where Flux_O+ is the O⁺ number flux in cm^-2s^-1 at 3R_E mapped to 1000 km altitude, f_e is the electron precipitation energy flux in ergs cm^-2 s^-1, and D_wave is the wave spectral density at 6.5 Hz in (mV)² m^-2 Hz^-1m and En is the characteristic energy of the precipitating electrons. Strangeway, R. J., R. E. Ergun, Y.-J. Su, C. W. Carlson, and R. C. Elphic, Factors controlling ionospheric outflows as observed at intermediate altitudes, J. Geophys. Res., 110, A03221, doi:10.1029/2004JA010829, 2005. Zheng, Y., T. E. Moore, F. S. Mozer, C. T. Russell, and R. J. Strangeway, Polar study of ionospheric ion outflow versus energy input, J. Geophys. Res., 110, A07210, doi:10.1029/2004JA010995, 2005.
DE: 2407 Auroral ionosphere (2704)
DE: 2431 Ionosphere/magnetosphere interactions (2736)
DE: 2704 Auroral phenomena (2407)
DE: 2736 Magnetosphere/ionosphere interactions (2431)
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Joint Assembly