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Author Drouot, T. ♦ Gravier, E. ♦ Reveille, T. ♦ Collard, M.
Source United States Department of Energy Office of Scientific and Technical Information
Content type Text
Language English
Subject Keyword PLASMA PHYSICS AND FUSION TECHNOLOGY ♦ BANANA REGIME ♦ DISTURBANCES ♦ ELECTRON DENSITY ♦ ELECTRON TEMPERATURE ♦ IONS ♦ PLASMA ♦ PLASMA INSTABILITY ♦ TRAPPED ELECTRONS ♦ TURBULENCE
Abstract This paper presents a study of zonal flows generated by trapped-electron mode and trapped-ion mode micro turbulence as a function of two plasma parameters—banana width and electron temperature. For this purpose, a gyrokinetic code considering only trapped particles is used. First, an analytical equation giving the predicted level of zonal flows is derived from the quasi-neutrality equation of our model, as a function of the density fluctuation levels and the banana widths. Then, the influence of the banana width on the number of zonal flows occurring in the system is studied using the gyrokinetic code. Finally, the impact of the temperature ratio T{sub e}/T{sub i} on the reduction of zonal flows is shown and a close link is highlighted between reduction and different gyro-and-bounce-average ion and electron density fluctuation levels. This reduction is found to be due to the amplitudes of gyro-and-bounce-average density perturbations n{sub e} and n{sub i} gradually becoming closer, which is in agreement with the analytical results given by the quasi-neutrality equation.
ISSN 1070664X
Educational Use Research
Learning Resource Type Article
Publisher Date 2015-10-15
Publisher Place United States
Journal Physics of Plasmas
Volume Number 22
Issue Number 10


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