Bibliography



Notice:

  • Clicking on the title will open a new window with all details of the bibliographic entry.
  • Clicking on the DOI link will open a new window with the original bibliographic entry from the publisher.
  • Clicking on a single author will show all publications by the selected author.
  • Clicking on a single keyword, will show all publications by the selected keyword.



Found 2 entries in the Bibliography.


Showing entries from 1 through 2


2021

Generation of realistic short chorus wave packets

Abstract Most lower-band chorus waves observed in the inner magnetosphere propagate under the form of moderately intense short wave packets with fast frequency and phase variations. Therefore, understanding the formation mechanism of such short wave packets is crucial for accurately modelling electron nonlinear acceleration or precipitation into the atmosphere by these waves. We compare chorus wave statistics from the Van Allen Probes with predictions from a simple model of short wave packet generation by wave superposition with resonance non-overlap, as well as with results from Vlasov Hybrid Simulations of chorus wave generation in an inhomogeneous magnetic field in the presence of one or two simultaneous triggering waves. We show that the observed moderate amplitude short chorus wave packets can be formed by a superposition of two or more waves generated near the magnetic equator with a sufficiently large frequency difference.

Nunn, D.; Zhang, X.-J.; Mourenas, D.; Artemyev, A.;

Published by: Geophysical Research Letters      Published on: 03/2021

YEAR: 2021     DOI: https://doi.org/10.1029/2020GL092178

chorus waves; Radiation belts; Wave-particle interaction; Van Allen Probes

2015

A computational and theoretical investigation of nonlinear wave-particle interactions in oblique whistlers

Most previous work on nonlinear wave-particle interactions between energetic electrons and VLF waves in the Earth\textquoterights magnetosphere has assumed parallel propagation, the underlying mechanism being nonlinear trapping of cyclotron resonant electrons in a parabolic magnetic field inhomogeneity. Here nonlinear wave-particle interaction in oblique whistlers in the Earth\textquoterights magnetosphere is investigated. The study is nonself-consistent and assumes an arbitrarily chosen wave field. We employ a \textquotedblleftcontinuous wave\textquotedblright wave field with constant frequency and amplitude, and a model for an individual VLF chorus element. We derive the equations of motion and trapping conditions in oblique whistlers. The resonant particle distribution function, resonant current, and nonlinear growth rate are computed as functions of position and time. For all resonances of order n, resonant electrons obey the trapping equation, and provided the wave amplitude is big enough for the prevailing obliquity, nonlinearity manifests itself by a \textquotedbllefthole\textquotedblright or \textquotedbllefthill\textquotedblright in distribution function, depending on the zero-order distribution function and on position. A key finding is that the n = 1 resonance is relatively unaffected by moderate obliquity up to 25\textdegree, but growth rates roll off rapidly at high obliquity. The n = 1 resonance saturates due to the adiabatic effect and here reaches a maximum growth at ~20 pT, 2000 km from the equator. Damping due to the n = 0 resonance is not subject to adiabatic effects and maximizes at some 8000 km from the equator at an obliquity ~55\textdegree.

Nunn, David; Omura, Yoshiharu;

Published by: Journal of Geophysical Research: Space Physics      Published on: 04/2015

YEAR: 2015     DOI: 10.1002/2014JA020898

Chorus; nonlinear process; oblique propagation; simulation; Wave-particle interaction; whistler



  1