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arXiv · 0901.2049

Quasilinear analysis of the zonal flow back-reaction on ion-temperature-gradient mode turbulence

Johan Anderson·Jiquan Li·Yasuaki Kishimoto·Eun-jin Kim
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Abstract

There is strong evidence in favor for zonal flow suppression of the Ion-Temperature-Gradient (ITG) mode turbulence, specifically close to the linear stability threshold. The present letter attempts to analytically calculate the effects of zonal flow suppression of the ITG turbulence through deriving a modified dispersion relation including the back-reaction of the zonal flows on the ITG turbulence based on the quasilinear theory. The results are manifested in a reduction of the linear growth rate and an increase in the effective linear ITG threshold.

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Johan Anderson, Jiquan Li, Yasuaki Kishimoto, Eun-jin Kim. 2009-01-14. Quasilinear analysis of the zonal flow back-reaction on ion-temperature-gradient mode turbulence. https://doi.org/10.1016/j.physleta.2008.08.003

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