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arXiv · 2406.03277

Turbulent relaxation patterns in SOL plasma

R Varennes·G Dif-Pradalier·P Ghendrih·V Grandgirard·O Panico·Y Sarazin·E Serre·D Zarzoso
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Abstract

Relaxations of localized over-density in a plane transverse to the magnetic field are numericallyinvestigated under the effect of drift-wave and interchange drives in SOL conditions. Such a controlleddeparture from thermodynamic equilibrium allows the investigation of fundamental processesat play in cross-field transport. Interchange instabilities generate ballistic outward radial flux withlow amplitude zonal flow patterns, whereas drift-wave instabilities result in symmetric radial fluxwith large amplitude zonal flow patterns. When both instabilities are considered, the combinedeffects tend to favor drift-waves, leading to a weaker outward flux with larger zonal flow patterns.

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R Varennes, G Dif-Pradalier, P Ghendrih, V Grandgirard, O Panico, Y Sarazin, E Serre, D Zarzoso. 2024-06-05. Turbulent relaxation patterns in SOL plasma. https://arxiv.org/abs/2406.03277

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