Electron pitch-angle diffusion: resonant scattering by waves vs.nonadiabatic effects

A.V. Artemyev (1, 2) , K.G. Orlova (3, 4) , Didier Mourenas (5) , O. V. Agapitov (2, 6) , V.V. Krasnoselskikh (2)

1 IKI - Space Research Institute of the Russian Academy of Sciences
2 LPC2E - Laboratoire de Physique et Chimie de l'Environnement et de l'Espace
3 SINP - D.V. Skobeltsyn Institute of Nuclear Physics
4 Department of Earth and Space Sciences [Los Angeles]
5 CEA Le Ripault - CEA Le Ripault
6 National Taras Shevchenko University of Kiev

In this paper we investigate the electron pitchangle diffusion coefficients in the night-side inner magnetosphere around the geostationary orbit (L 7) due to magnetic field deformation. We compare the effects of resonant wave–particle scattering by lower band chorus waves and the adiabaticity violation of electron motion due to the strong curvature of field lines in the vicinity of the equator. For a realistic magnetic field configuration, the nonadiabatic effects are more important than the wave–particle interactions for high energy (> 1 MeV) electrons. For smaller energy, the scattering by waves is more effective than nonadiabatic one. Moreover, the role of nonadiabatic effects increases with particle energy. Therefore, to model electron scattering and transport in the night-side inner magnetosphere, it is important to take into account the peculiarities of high-energy electron dynamics.

Keywords: Magnetospheric physics (energetic particles; precipitating) – space plasma physics (charged particle motion and acceleration; wave–particle interactions)

Domains: Sciences of the Universe [physics]

A.V. Artemyev, K.G. Orlova, Didier Mourenas, O. V. Agapitov, V.V. Krasnoselskikh. Electron pitch-angle diffusion: resonant scattering by waves vs.nonadiabatic effects. Annales Geophysicae, 2013, 31, pp.1485-1490. ⟨10.5194/angeo-31-1485-2013⟩. ⟨insu-01174680⟩