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تسجيل مستخدم جديدThe role Alfven waves in the generation of Earth polar auroras
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تأليف
Fabrice Mottez
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The acceleration of electrons at 1-10 keV energies is the cause of the polar aurora displays, and an important factor of magnetic energy transfer from the solar wind to the Earth. Two main families of acceleration processes are observed: those based on coherent quasi-static structures called double layers, and those based of the propagation of Alfven Waves (AW). This paper is a review of the Alfvenic acceleration processes, and of their role in the global dynamics of the auroral zone.
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In the Earth auroral zone, the electron acceleration by Alfven waves is sometimes a precursor of the non-propagating acceleration structures. In order to investigate how Alfven waves could generate non-propagating electric fields, a series of simulat
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