On the Connection Between Microbursts and Nonlinear Electronic Structures in Planetary Radiation Belts

TitleOn the Connection Between Microbursts and Nonlinear Electronic Structures in Planetary Radiation Belts
Publication TypeJournal Article
Year of Publication2016
AuthorsOsmane, A, III, LBWilson, Blum, L, Pulkkinen, TI
JournalThe Astrophysical Journal
Volume816
Issue2
Pagination51
Date Published01/2016
Keywordsacceleration of particles; Earth; Plasmas; relativistic processes; solar–terrestrial relations; Van Allen Probes; waves
AbstractUsing a dynamical-system approach, we have investigated the efficiency of large-amplitude whistler waves for causing microburst precipitation in planetary radiation belts by modeling the microburst energy and particle fluxes produced as a result of nonlinear wave–particle interactions. We show that wave parameters, consistent with large-amplitude oblique whistlers, can commonly generate microbursts of electrons with hundreds of keV-energies as a result of Landau trapping. Relativistic microbursts (>1 MeV) can also be generated by a similar mechanism, but require waves with large propagation angles ${\theta }_{{kB}}\gt 50^\circ $ and phase-speeds ${v}_{{\rm{\Phi }}}\geqslant c/9$. Using our result for precipitating density and energy fluxes, we argue that holes in the distribution function of electrons near the magnetic mirror point can result in the generation of double layers and electron solitary holes consistent in scales (of the order of Debye lengths) to nonlinear structures observed in the radiation belts by the Van Allen Probes. Our results indicate a relationship between nonlinear electrostatic and electromagnetic structures in the dynamics of planetary radiation belts and their role in the cyclical production of energetic electrons ($E\geqslant 100$ keV) on kinetic timescales, which is much faster than previously inferred.
URLhttp://stacks.iop.org/0004-637X/816/i=2/a=51?key=crossref.70d237eeae19ada88cf791dd9ba676be
DOI10.3847/0004-637X/816/2/51
Short TitleApJ


Page Last Modified: May 10, 2016