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arXiv · 1203.1174

High Frequency Geodesic Acoustic Modes in Electron Temperature Gradient Mode Turbulence

Johan Anderson·Hans Nordman·Raghvendra Singh·Predhiman Kaw
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Abstract

In this work the first demonstration of a high frequency branch of the geodesic acoustic mode (GAM) driven by electron temperature gradient (ETG) modes is presented. The work is based on a fluid description of the ETG mode retaining non-adiabatic ions and the dispersion relation for high frequency GAMs driven nonlinearly by ETG modes is derived. A new saturation mechanism for ETG turbulence through the interaction with high frequency GAMs is found, resulting in a significantly enhanced ETG turbulence saturation level compared to the mixing length estimate.

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Johan Anderson, Hans Nordman, Raghvendra Singh, Predhiman Kaw. 2012-03-06. High Frequency Geodesic Acoustic Modes in Electron Temperature Gradient Mode Turbulence. https://doi.org/10.1063/1.4742321

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