2014/04/30 by Bogdan Teaca, Alejandro Bañón Navarro, Frank Jenko
Physics and Astronomy · #Adiabatic process #Coupling (piping) #Electron #Electron temperature #Gyrokinetics #Ionosphere and magnetosphere dynamics #Magnetic confinement fusion research #Nonlinear system #Plasma #Solar and Space Plasma Dynamics #Toroid #Turbulence #Zonal flow (plasma) #physics.plasm-ph
paper · pdf · doi:10.1063/1.4890127
15 pages, 14 figures
openalex publication_date 2014/07/01 · arxiv created 2014/07/03 · arxiv updated 2015/06/19 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
In magnetized plasma turbulence, the couplings of perpendicular spatial scales that arise due to the nonlinear interactions are analyzed from the perspective of the free-energy exchanges. The plasmas considered here, with appropriate ion or electron adiabatic electro-neutrality responses, are described by the gyrokinetic formalism in a toroidal magnetic geometry. Turbulence develops due to the electrostatic fluctuations driven by temperature gradient instabilities, either ion temperature gradient (ITG) or electron temperature gradient (ETG). The analysis consists in decomposing the system into a series of scale structures, while accounting separately for contributions made by modes possessing special symmetries (e.g., the zonal flow modes). The interaction of these scales is analyzed using the energy transfer functions, including a forward and backward decomposition, scale fluxes, and locality functions. The comparison between the ITG and ETG cases shows that ETG turbulence has a more pronounced classical turbulent behavior, exhibiting a stronger energy cascade, with implications for gyrokinetic turbulence modeling.