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Excitation of zonal flow by the modulational instability in electron temperature gradient driven turbulence

Yu. A. Zaliznyak·A. I. Yakimenko·V. M. Lashkin
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Abstract

The generation of large-scale zonal flows by small-scale electrostatic drift waves in electron temperature gradient(ETG) driven turbulence model is considered. The generation mechanism is based on the modulational instability of a finite amplitude monochromatic drift wave. The threshold and growth rate of the instability as well as the optimal spatial scale of zonal flow are obtained.

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Yu. A. Zaliznyak, A. I. Yakimenko, V. M. Lashkin. 2007-03-05. Excitation of zonal flow by the modulational instability in electron temperature gradient driven turbulence. https://doi.org/10.1017/s0022377807006988

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