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Found 4 entries in the Bibliography.
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2017 
Radial transport of radiation belt electrons in kinetic fieldline 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 driftbounce resonances in kinetic Alfv\ en eigenmodes/kinetic fieldline resonances. Estimated diffusion coefficients indicate timescales for radial transport of the order of hours in stormtime events at energies from <100 keV to MeVs over equatorial pitch angles from the edge of the loss cone to nearly perpendicular to the geomagnetic field. The correlation of kinetic resonances with electron depletions and enhancements during storm main phase and recovery, and the rapid diffusion these waves drive, suggest they may modulate the outer radiation belt. Chaston, C.; Bonnell, J.; Wygant, J.; Reeves, G.; Baker, D.; Melrose, D.; Cairns, Iver.; Published by: Geophysical Research Letters Published on: 07/2017 YEAR: 2017 DOI: 10.1002/2017GL074587 Alfven waves; Diffusion; field line resonances; Radiation belts; Transport; Van Allen Probes 
Spectra of keV protons related to ioncyclotron wave packets We use the FokkerPlanckKolmogorov equation to study the statistical aspects of stochastic dynamics of the radiation belt (RB) protons driven by nonlinear electromagnetic ioncyclotron (EMIC) wave packets. We obtain the spectra of keV protons scattered by these waves that show steeping near the gyroresonance, the signature of resonant waveparticle 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 waveparticle interaction, namely, the scattering of RB protons into the loss cone by EMIC waves. Khazanov, K.; Sibeck, D.; Tel\textquoterightnikhin, A.; Kronberg, T.; Published by: Physics of Plasmas Published on: 01/2017 YEAR: 2017 DOI: http://dx.doi.org/10.1063/1.4973323 Diffusion; Particle precipitation; protons; Van Allen Probes; wave particle interactions; Wave power 
2014 
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 splittingrelated anomalous diffusion for outer zone electrons compared to conventional diffusion in the absence of drift shell splitting. We assume the primary local scattering process is waveparticle interactions with chorus. We find that anomalous radial diffusion can exceed that of conventional drift resonant radial diffusion for particles with energies near 0.1 MeV at all radial distances outside the plasmasphere during quiet to moderate geomagnetic activity and, it is significant at 0.5 MeV. Cross diffusion involving the radial invariant can exceed the geometric mean of the corresponding pure diffusion coefficients at 0.1 MeV, and that such cross diffusion is significant even at 0.51 MeV. At 1 MeV, cross diffusion is often significant. The highest radial distances and magnetic activity levels in our study do not always exhibit as much significant anomalous diffusion as moderate radial distances and activity levels. This can be explained by (a) stronger dependence of conventional diffusion on magnetic activity and radius, and (b) strongest drift shell splitting at moderate magnetic activity. Simulation codes that neglect the possibility for cross terms will likely systematically underperform, especially for 0.10.5 MeV electrons, for much of the outer zone for quiet to moderate levels of magnetic activity. Published by: Journal of Geophysical Research: Space Physics Published on: 12/2014 YEAR: 2014 DOI: 10.1002/2014JA020422 
Relativistic electron precipitation events driven by electromagnetic ioncyclotron 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, and relativistic electron precipitation events, that are manifested on large temporal scales of the order of the diffusion time \~tens of minutes. Khazanov, G.; Sibeck, D.; Tel\textquoterightnikhin, A.; Kronberg, T.; Published by: Physics of Plasmas Published on: 08/2014 YEAR: 2014 DOI: 10.1063/1.4892185 Diffusion; Electron scattering; Nonlinear waves; waveparticle interactions; Whistler waves 
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