HR: 1330h
AN: SM12A-1202    [PDF]
TI: Modeling Polar Cap Field-aligned Electron Density Profiles Measured with IMAGE Radio Plasma Imager
AU: Tu, J
EM: tuj@cspar.uah.edu
AF: Center for Space Plasma and Aeronomic Research, the University of Alabama in Huntsville, Huntsville, AL 35899 United States
AU: Horwitz, J L
EM: horwitzj@cspar.uah.edu
AF: Center for Space Plasma and Aeronomic Research, the University of Alabama in Huntsville, Huntsville, AL 35899 United States
AU: Nsumei, P A
EM: Patrick_Nsumei@student.uml.edu
AF: Department of Environmental, Earth, and Atmospheric Science and Center for Atmospheric Research, University of Massachusetts Lowell, Lowell, MA 01854 United States
AU: Song, P
EM: Paul_Song@uml.edu
AF: Department of Environmental, Earth, and Atmospheric Science and Center for Atmospheric Research, University of Massachusetts Lowell, Lowell, MA 01854 United States
AU: Huang, X
EM: Xueqin_Huang@uml.edu
AF: Department of Environmental, Earth, and Atmospheric Science and Center for Atmospheric Research, University of Massachusetts Lowell, Lowell, MA 01854 United States
AU: Reinisch, B W
EM: bodo_reinisch@uml.edu
AF: Department of Environmental, Earth, and Atmospheric Science and Center for Atmospheric Research, University of Massachusetts Lowell, Lowell, MA 01854 United States
AU: * Zeng, W
EM: zengw@cspar.uah.edu
AF: Center for Space Plasma and Aeronomic Research, the University of Alabama in Huntsville, Huntsville, AL 35899 United States
AB: A dynamic fluid semi-kinetic (DyFK) model is used to simulate the ion field-aligned flows within flux tubes drifting along a model specified convection line across the polar ionosphere. In this DyFK model, the collision dominated portion of the flux tube is treated with a moment-based fluid model for altitudes from 120 to 1100 km, while the generalized semi-kinetic model is used for 1100 km to 3 RE region. The effects of auroral soft electron precipitation, centrifugal acceleration, wave-driven transverse ion heating and parallel potentials are incorporated into the simulation of the ion field-aligned transport. The modeled field-aligned electron density profiles in the polar cap are compared with several field-aligned density profiles measured by the Radio Plasma Instrument (RPI) on the IMAGE satellite on March 4, 2003, in a weak magnetic storm (minimum Dst value of -58 nT). The electron densities were substantially elevated during the magnetic storm, with electron density reaching ~10 cm-3 at 2.8 RE altitude. It is found that reasonable parameters for the indicated aurora processes could raise the modeled electron densities to the level of the densities measured by the IMAGE/RPI. The simulation results indicate that the O+ becomes the dominant ion species in the altitude range considered for high density cases.
DE: 2431 Ionosphere/magnetosphere interactions (2736)
DE: 2467 Plasma temperature and density
DE: 2475 Polar cap ionosphere
DE: 2776 Polar cap phenomena
SC: SPA - Magnetospheric Physics [SM]
MN: 2003 Fall Meeting