Found 4 entries in the Bibliography.

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Radial transport of radiation belt electrons in kinetic field-line resonances

A representative case study from the Van Allen Probes during a geomagnetic storm recovery phase reveals enhanced electron fluxes at intermediate pitch angles over energies from ~100 keV to 5 MeV coincident with broadband low frequency electromagnetic waves. The statistical properties of these waves are used to build a model for radial diffusion via drift-bounce resonances in kinetic Alfv\ en eigenmodes/kinetic field-line resonances. Estimated diffusion coefficients indicate timescales for radial transport of the order of hou ...

Chaston, C.; Bonnell, J.; Wygant, J.; Reeves, G.; Baker, D.; Melrose, D.; Cairns, Iver.;

YEAR: 2017     DOI: 10.1002/2017GL074587

Alfven waves; Diffusion; field line resonances; Radiation belts; Transport; Van Allen Probes

Spectra of keV protons related to ion-cyclotron wave packets

We use the Fokker-Planck-Kolmogorov equation to study the statistical aspects of stochastic dynamics of the radiation belt (RB) protons driven by nonlinear electromagnetic ion-cyclotron (EMIC) wave packets. We obtain the spectra of keV protons scattered by these waves that show steeping near the gyroresonance, the signature of resonant wave-particle interaction that cannot be described by a simple power law. The most likely mechanism for proton precipitation events in RBs is shown to be nonlinear wave-particle interaction, n ...

Khazanov, K.; Sibeck, D.; Tel\textquoterightnikhin, A.; Kronberg, T.;

YEAR: 2017     DOI:

Diffusion; Particle precipitation; protons; Van Allen Probes; wave particle interactions; Wave power


The activity and radial dependence of anomalous diffusion by pitch-angle scattering on split magnetic drift shells

Asymmetries in the magnetospheric magnetic field produce drift shell splitting, which causes the radial (drift shell) invariant to sometimes depend on pitch angle. Where drift shell splitting is significant, pitch angle scattering leads to diffusion in all three invariants of the particle\textquoterights motion, including cross diffusion. We examine the magnitude of drift shell splitting-related anomalous diffusion for outer zone electrons compared to conventional diffusion in the absence of drift shell splitting. We assume ...

O\textquoterightBrien, T.P.;

YEAR: 2014     DOI: 10.1002/2014JA020422

Diffusion; Drift shell splitting; Radiation belt

Relativistic electron precipitation events driven by electromagnetic ion-cyclotron waves

We adopt a canonical approach to describe the stochastic motion of relativistic belt electrons and their scattering into the loss cone by nonlinear EMIC waves. The estimated rate of scattering is sufficient to account for the rate and intensity of bursty electron precipitation. This interaction is shown to result in particle scattering into the loss cone, forming \~10 s microbursts of precipitating electrons. These dynamics can account for the statistical correlations between processes of energization, pitch angle scattering ...

Khazanov, G.; Sibeck, D.; Tel\textquoterightnikhin, A.; Kronberg, T.;

YEAR: 2014     DOI: 10.1063/1.4892185

Diffusion; Electron scattering; Nonlinear waves; wave-particle interactions; Whistler waves