Indirect nonlinear interaction between toroidal Alfv\'en eigenmode and ion temperature gradient mode mediated by zonal structures
Plasma Physics
2024-08-29 v1
Abstract
The indirect nonlinear interactions between toroidal Alfv\'en eigenmode (TAE) and ion temperature gradient mode (ITG) are investigated using nonlinear gyrokinetic theory and ballooning mode formalism. More specifically, the local nonlinear ITG mode equation is derived adopting the fluid-ion approximation, with the contributions of zonal field structure and phase space zonal structure beat-driven by finite amplitude TAE accounted for on the same footing. The obtained nonlinear ITG mode equation is solved both analytically and numerically, and it is found that, the zonal structure beat-driven by TAE has only weakly destabilizing effects on ITG, contrary to usual speculations and existing numerical results.
Cite
@article{arxiv.2408.15782,
title = {Indirect nonlinear interaction between toroidal Alfv\'en eigenmode and ion temperature gradient mode mediated by zonal structures},
author = {Qian Fang and Guangyu Wei and Ningfei Chen and Liu Chen and Fulvio Zonca and Zhiyong Qiu},
journal= {arXiv preprint arXiv:2408.15782},
year = {2024}
}