HR: 1340h
AN: SM53B-1285    [Abstracts]
TI: Drift-Resonant Interaction of Magnetospheric Relativistic Electrons with Ultra-Low Frequency (ULF) Waves: Comparison between Observations and Simulations
AU: * Shao, X
EM: xshcn@astro.umd.edu
AF: Department of Astronomy, University of Maryland, College Park, MD 20742, United States
AU: Fung, S
EM: fung@mail630.gsfc.nasa.gov
AF: Space Physics Data Facility, NASA/GSFC, Greenbelt, MD 20717, United States
AU: Tan, L
EM: ltan@mail630.gsfc.nasa.gov
AF: Perot Systems, Perot Systems, Fairfax, VA 22031, United States
AU: Papadopoulos, K
EM: dpapadop@umd.edu
AF: Department of Astronomy, University of Maryland, College Park, MD 20742, United States
AB: By analyzing CRRES and GOES observations on Aug. 27 1991, Tan et al. [2004] reported evidence of magnetospheric relativistic electron acceleration by resonant interactions with PC5 ULF waves. The event showed strong ULF wave activities after a storm sudden commencement (SSC) and energetic electron fluxes were enhanced in 2 hours. The electron flux peak observed in energy channels (0.6 – 1.1 MeV) were modulated by local electric field observed by CRRES. In this study, we set up a drift-resonant interaction model between ULF wave and magnetospheric relativistic electrons to model the observed electron flux in the event. In this model, the poloidal mode wave is concentrated in the dayside and the toroidal mode wave is concentrated in two flanks. The toroidal mode waves in the dawn and dusk flanks are in anti-phase. We found that electron can be accelerated jointly by the poloidal wave in the dayside and toroidal wave in flanks. The dayside poloidal wave serves as the dominant source of electron acceleration. The simulated electron flux variations agree well with observations both in fine details and long period behavior. These agreements in electron behavior indicate that the ULF wave plays an important role in accelerating MeV relativistic electrons around the geosynchronous orbit. General applications of the model during SSC events are also discussed. Tan, L. C., S. F. Fung, and X. Shao, Observation of magnetospheric relativistic electrons accelerated by Pc-5 ULF waves, Geophys. Rev. Lett., L14802, doi: 10.1029/2004GL019459, 2004.
DE: 2483 Wave/particle interactions (7867)
DE: 2716 Energetic particles: precipitating
DE: 2774 Radiation belts
DE: 2788 Magnetic storms and substorms (7954)
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Fall Meeting