Short Wavelength Geodesic Acoustic Mode Excitation by Energetic Particles

Liu Chen; Zhiyong Qiu; Fulvio Zonca

doi:10.1063/1.5003142

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arXiv · 1709.02085

Short Wavelength Geodesic Acoustic Mode Excitation by Energetic Particles

Liu Chen·Zhiyong Qiu·Fulvio Zonca

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Abstract

Taking the collisionless damping of geodesic acoustic mode (GAM) as an example, the physics processes underlying wave particle resonances in the short wavelength limit are clarified. As illus- trative application, GAM excitation by energetic particles in short wavelength limit is investigated assuming a single pitch angle slowing-down fast ion equilibrium distribution function. Conditions for this energetic particle-induced GAM (EGAM) to be unstable are discussed.

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Liu Chen, Zhiyong Qiu, Fulvio Zonca. 2017-09-07. Short Wavelength Geodesic Acoustic Mode Excitation by Energetic Particles. https://doi.org/10.1063/1.5003142

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