Maeyama S, Watanabe T-H, Ishizawa A
Department of Physics, Nagoya University, Nagoya 464-8602, Japan.
Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan.
Phys Rev Lett. 2017 Nov 10;119(19):195002. doi: 10.1103/PhysRevLett.119.195002. Epub 2017 Nov 9.
Gyrokinetic turbulence simulations are applied for the first time to the cross-scale interactions of microtearing modes (MTMs) and electron-temperature-gradient (ETG) modes. The investigation of the fluctuation response in a multiscale simulation including both types of instabilities indicates that MTMs are suppressed by ETG turbulence. A detailed analysis of nonlinear mode coupling reveals that radially localized current-sheet structures of MTMs are strongly distorted by fine-scale E×B flows of ETG turbulence. Consequently, electron heat transport caused by the magnetic flutter of MTMs is significantly reduced and ETG turbulence dominates electron heat transport.
回旋动理学湍流模拟首次应用于微撕裂模（MTM）与电子温度梯度（ETG）模的跨尺度相互作用。对包含这两种不稳定性的多尺度模拟中的涨落响应进行的研究表明，MTM被ETG湍流所抑制。对非线性模耦合的详细分析揭示，MTM的径向局域电流片结构被ETG湍流的精细尺度E×B流强烈扭曲。因此，由MTM的磁脉动引起的电子热输运显著降低，ETG湍流主导电子热输运。
