Comparative studies of nonlinear ITG and ETG dynamics
نویسندگان
چکیده
It is shown that the ITG-ETG symmetry is nonlinearly broken due to the different response of respectively electrons and ions to Zonal Flows (ZF). ITG is dominated by ITG-ZF nonlinear interactions and turbulence spreading, resulting in size-scaling of the associated turbulent transport. Meanwhile, nonlinear toroidal mode coupling dominates ETG saturation and ETG-ZF interactions enter on the longest nonlinear time scale only. The ETG turbulent transport level is smaller than values of experimental relevance.
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