Fast transport of resonant electrons in phase space due to nonlinear trapping by whistler waves

A.V. Artemyev (1) , A.A. Vasiliev (1) , D Mourenas (2) , O. V. Agapitov (3, 4) , V Krasnoselskikh (5) , D Boscher (6) , G Rolland (7)

1 IKI - Space Research Institute of the Russian Academy of Sciences
2 CEA-DAM - Centre d'Études de Limeil-Valenton
3 Department of Astronomy and Space Physics [Kyiv]
4 SSL - Space Sciences Laboratory [Berkeley]
5 LPC2E - Laboratoire de Physique et Chimie de l'Environnement et de l'Espace
6 ONERA - The French Aerospace Lab [Toulouse]
7 CNES - Centre National d'Études Spatiales [Toulouse]

We present an analytical, simplified formulation accounting for the fast transport of relativistic electrons in phase space due to wave-particle resonant interactions in the inhomogeneous magnetic field of Earth's radiation belts. We show that the usual description of the evolution of the particle velocity distribution based on the Fokker-Planck equation can be modified to incorporate nonlinear processes of wave-particle interaction, including particle trapping. Such a modification consists in one additional operator describing fast particle jumps in phase space. The proposed, general approach is used to describe the acceleration of relativistic electrons by oblique whistler waves in the radiation belts. We demonstrate that for a wave power distribution with a hard enough power law tail inline image such that η < 5/2, the efficiency of nonlinear acceleration could be more effective than the conventional quasi-linear acceleration for 100 keV electrons.

Domains: Sciences of the Universe [physics]

A.V. Artemyev, A.A. Vasiliev, D Mourenas, O. V. Agapitov, V Krasnoselskikh, et al.. Fast transport of resonant electrons in phase space due to nonlinear trapping by whistler waves. Geophysical Research Letters, 2014, 41, pp.5727-5733. ⟨10.1002/2014GL061380⟩. ⟨insu-01171239⟩