HR: 0800h
AN: SM31B-0453    [Abstracts]
TI: Fluid-kinetic simulations of the passage of Storm Enhanced Density (SED) plasma flux tubes through the dayside cleft auroral processes region
AU: * Zeng, W
EM: zengw@uta.edu
AF: Department of Physics, the University of Texas at Arlington, 502 Yates St. Box 19059, Arlington, TX 76019, United States
AU: Horwitz, J L
EM: horwitz@uta.edu
AF: Department of Physics, the University of Texas at Arlington, 502 Yates St. Box 19059, Arlington, TX 76019, United States
AB: Foster et al. [2002] and others have reported on elevated ionospheric density regions being convected from the subauroral plasmaspheric region toward noon, in association with convection of plasmaspheric tails in the dayside magnetosphere. It has been suggested that these so-called Storm Enhanced Density (SED) regions could serve as ionospheric plasma source populations for cleft ion fountain outflows. To investigate this scenario, we have used our Dynamic Fluid Kinetic (DyFK) model to simulate the entry of a high-density "plasmasphere-like" flux tube entering the cleft region and subjected to an episode of wave-driven transverse ion heating. We find that the O⁺ ion density at higher altitudes increases and the density at lower altitudes decreases, following this heating episode, indicating increased numbers of O⁺ ions from the ionospheric source gain sufficient energy to reach higher altitudes after the effects of transverse wave heating. We also find that O⁺- H⁺ crossing point in topside ionosphere moves upward as the wave heating continues. Foster, J. C., P. J. Erickson, A. J. Coster, J. Goldstein, and F. J. Rich, Ionospheric signatures of plasmaspheric tails, Geophys. Res. Lett., 29(13), 1623, doi:10.1029/2002GL015067, 2002.
DE: 2431 Ionosphere/magnetosphere interactions (2736)
DE: 2475 Polar cap ionosphere
DE: 2481 Topside ionosphere
DE: 2483 Wave/particle interactions (7867)
DE: 7949 Ionospheric storms (2441)
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Fall Meeting