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| 05/06/02
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MOTTEZ Fabrice |
CETP/CNRS |
| 10-12 avenue de l'Europe | SF2A- PNG- PNP- PNST- |
|
78140 |
Velizy, F |
Presentation 1 : Poster
Acceleration by Alfven Waves and density gradients in astrophysical plasmas
F. Mottez (CETP), V. Genot (Queen Mary Coll., UK), P. Louarn (CESR)
The simultaneous occurence of Alfvén waves and density gradients
might be a very common feature of astrophysical plasmas. We investigate (theory + simulation) the case of the highly magnetized plasma of the auroral zone of the Earth magnetosphere. We show that parallel electric fields are generated on the density gradients leading to an efficient electron acceleration, to the formation of electron beams and the growth of plasma turbulence. These results are consistent with the observations, they could explain the plasma acceleration associated to small scale auroral arcs.This process may have other astrophysical applications related to acceleration in highly magnetized plasmas.