Nonlinear saturation of toroidal Alfven eigenmodes via nonlinear mode couplings

Zhiyong Qiu; Liu Chen; Fulvio Zonca; Wei Chen

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arXiv · 1810.05300

Nonlinear saturation of toroidal Alfven eigenmodes via nonlinear mode couplings

Zhiyong Qiu·Liu Chen·Fulvio Zonca·Wei Chen

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Abstract

Gyrokinetic theory of nonlinear mode coupling as a mechanism for toroidal Alfven eigenmode (TAE) saturation in the fusion plasma related parameter regime is presented, including 1) para- metric decay of TAE into lower kinetic TAE (LKTAE) and geodesic acoustic mode (GAM), and 2) enhanced TAE coupling to shear Alfven wave (SAW) continuum via ion induced scattering. Our theory shows that, for TAE saturation in the parameter range of practical interest, several processes with comparable scattering cross sections can be equally important.

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Zhiyong Qiu, Liu Chen, Fulvio Zonca, Wei Chen. 2018-10-12. Nonlinear saturation of toroidal Alfven eigenmodes via nonlinear mode couplings. https://arxiv.org/abs/1810.05300

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