ANGEO Annales Geophysicae ANGEO Ann. Geophys. 1432-0576 Copernicus Publications Göttingen, Germany 10.5194/angeo-31-1485-2013 Electron pitch-angle diffusion: resonant scattering by waves vs. nonadiabatic effects Artemyev A. V. 1 2 Orlova K. G. 3 4 Mourenas D. 5 Agapitov O. V. https://orcid.org/0000-0001-6427-1596 1 6 Krasnoselskikh V. V. 1 LPC2E/CNRS – University of Orleans, UMR7328, Orleans, France Space Research Institute, RAS, Moscow, Russian Federation Department of Earth and Space Sciences, University of California, Los Angeles, CA, USA Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, Moscow, Russian Federation CEA, DAM, DIF, 91297, Arpajon, France National Taras Shevchenko University of Kiev, Kiev, Ukraine 05 09 2013 31 9 1485 1490 Copyright: © 2013 A. V. Artemyev et al. 2013 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://angeo.copernicus.org/articles/31/1485/2013/angeo-31-1485-2013.html The full text article is available as a PDF file from https://angeo.copernicus.org/articles/31/1485/2013/angeo-31-1485-2013.pdf

In this paper we investigate the electron pitch-angle diffusion coefficients in the night-side inner magnetosphere around the geostationary orbit (<I>L</I> ~ 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 (&gt; 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.

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