Soliton generation and drift wave turbulence spreading via geodesic acoustic mode excitation
نویسندگان
چکیده
The two-field equations governing fully nonlinear dynamics of the drift wave (DW) and geodesic acoustic mode (GAM) in toroidal geometry are derived gyrokinetic framework. Two stages with distinctive features identified analyzed. In linear growth stage, set can be reduced to intensively studied parametric decay instability (PDI), accounting for spontaneous resonant excitation GAM by DW. main results previous works on excitation, e.g., much enhanced group velocity rate GAM, reproduced from numerical solution equations. soliton structures observed form due balancing self-trapping effect spontaneously excited kinetic dispersiveness enhance turbulence spreading DW linearly unstable stable region, exhibiting convective propagation instead typical dispersive process, is thus, expected induce core-edge interaction nonlocal transport.
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ژورنال
عنوان ژورنال: Plasma Physics and Controlled Fusion
سال: 2021
ISSN: ['1361-6587', '0741-3335']
DOI: https://doi.org/10.1088/1361-6587/ac35a6