HR: 1340h
AN: SM33A-0431    [Abstracts]
TI: Wave-particle interactions in the source region of whistler-mode chorus
AU: * Santolik, O
EM: ondrej.santolik@mff.cuni.cz
AF: Charles University and IAP, ASCR, Prague, 18000 Czech Republic
AU: Meredith, N
SM33A-0431 AF: BAS, NERC, Cambridge, CB3 0ET United Kingdom
AU: Gurnett, D
SM33A-0431 AF: University of Iowa, Department of Physics and Astronomy, Iowa City, 52242 United States
AU: Pickett, J
SM33A-0431 AF: University of Iowa, Department of Physics and Astronomy, Iowa City, 52242 United States
AU: Menietti, J
SM33A-0431 AF: University of Iowa, Department of Physics and Astronomy, Iowa City, 52242 United States
AU: Parrot, M
SM33A-0431 AF: LPCE, CNRS, Orleans, 45071 France
AU: Winningham, D
SM33A-0431 AF: SWRI, San Antonio, Texas, 78228 United States
AU: Decreau, P
SM33A-0431 AF: LPCE, CNRS, Orleans, 45071 France
AU: Fazakerley, A
SM33A-0431 AF: MSSL, University College London, Surrey, RH5 6NT United Kingdom
AU: Cornilleau-Wehrlin, N
SM33A-0431 AF: CETP, IPSL, Velizy, 78140 France
AB: We investigate the source region of whistler mode chorus using combined wave and particle measurements from the Cluster spacecraft. The source region is identified by the Poynting flux and electromagnetic planarity analysis using multicomponent measurements of three magnetic and two electric antennas. To investigate time-frequency properties of chorus/hiss wave emissions we analyze high-resolution waveforms recorded in the source region. We estimate stability of these waves and their possible source mechanisms using simultaneous measurements of the distribution functions of electrons with energies up to 27 keV. These measurements show the presence of time-energy dispersed injected electrons at energies of tens to hundreds of eV with a large temperature anisotropy, and a loss cone distribution due to the radiation belt electrons with energies < 27 keV. We use a parametric model of the electron distribution function, and we estimate parameters of this model from the measurements by a nonlinear maximum likelihood method. We also use active sounding measurements of the total plasma density to complete the model by including a cold core component. The derived electron distribution model is found to be able to provide a source of free energy for the growth of the observed whistler-mode waves.
UR: http://os.matfyz.cz/papers/agu2005
DE: 2772 Plasma waves and instabilities (2471)
DE: 6984 Waves in plasma (7867)
DE: 7867 Wave/particle interactions (2483, 6984)
SC: SPA-Magnetospheric Physics [SM]
MN: Fall Meeting 2005