Density fluctuation of geodesic acoustic mode on the HL-2A tokamak
Density fluctuation of geodesic acoustic mode on the HL-2A tokamak
复制标题
HL-2A托卡马克测地线声模密度涨落
DOI：
10.1088/0029-5515/49/8/085030
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发表时间：
2009-07
期刊：
影响因子：
3.3
通讯作者：
中科院分区：
文献类型：
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作者：
在 HL-2A 托卡马克上结合耙式和三步朗缪尔探针阵列，在欧姆氘等离子体放电中观察到测地声波模式 (GAM) 的密度波动。采用极向和环形间距分别为 36 和 1330mm 的探针阵列来测量 GAM 密度波动的光谱特性和间歇性。首次同时测量了波动的极向和环形模数。实测波动幅度与理论预测一致。首次观察到在同一磁通表面上环形分离37.5°的GAM密度波动的高相干性和接近零相移，表明GAM在环形方向上的对称结构。中平面上方和下方波动的互相关函数的峰值时间延迟表明了预期的 sin θ 依赖性。 GAM 和环境湍流之间的非线性三波耦合被证明是产生 GAM 密度波动的合理机制。原始数据与高频环境湍流包络之间的显着相干性和相应的固定相移（∼π）为包络调制提供了实验证据。 GAM 振幅与粒子通量异相。大多数粒子通量的间歇频率接近 GAM 频率。
The density fluctuations of the geodesic acoustic mode (GAM) have been observed in Ohmic deuterium plasma discharges with a combination of rake-like and three-step Langmuir probe arrays on the HL-2A tokamak. The probe arrays with poloidal and toroidal separations of 36 and 1330 mm are applied to measure the spectral property and intermittency of the GAM density fluctuations. The poloidal and toroidal mode numbers of the fluctuations are simultaneously measured for the first time. The measured fluctuation amplitude is consistent with the theoretical prediction. High coherence and near zero phase shift of the GAM density fluctuations separated toroidally by 37.5° at the same magnetic flux surface was first observed, indicating the symmetric structure of the GAM in the toroidal direction. The peak time delays of the cross-correlation function of the fluctuations above and below the midplane suggest the expected sin θ dependence. The nonlinear three wave coupling between the GAM and the ambient turbulence is shown to be a plausible mechanism for the generation of the GAM density fluctuations. The significant coherence and the corresponding fixed phase shift (∼π) between the original data and the envelope of the high frequency ambient turbulence provide the experimental evidence for the envelope modulation. The GAM amplitude is out of phase with the particle flux. Most of the intermittent frequencies for particle flux are close to the GAM frequency.
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HL-2A托卡马克测地线声模的频谱特性
影响因子：
2.2
作者：
通讯作者：
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影响因子：
2.2
作者：
Y. Nagashima;K. Itoh;S. Itoh;A. Fujisawa;Masatoshi Yagi;Katsumichi Hoshino;K. Shinohara;A. Ejiri;Y. Takase;T. Ido;K. Uehara;Y. Miura
通讯作者：
Y. Nagashima;K. Itoh;S. Itoh;A. Fujisawa;Masatoshi Yagi;Katsumichi Hoshino;K. Shinohara;A. Ejiri;Y. Takase;T. Ido;K. Uehara;Y. Miura
DOI：
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发表时间：
2008
期刊：
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影响因子：
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作者：
A. Liu;T. Lan;H. Zhao;C. Yu;L. Yan;J. Dong;W. Hong;K. Zhao;J. Qian;J. Cheng;D. L. Yu;Q. Yang
通讯作者：
A. Liu;T. Lan;H. Zhao;C. Yu;L. Yan;J. Dong;W. Hong;K. Zhao;J. Qian;J. Cheng;D. L. Yu;Q. Yang
影响因子：
2.2
作者：
Conway, GD;Scott, B;Kendl, A
通讯作者：
Kendl, A
HL-2A 托卡马克等离子体中两种不同的湍流状态
影响因子：
3.3
作者：
通讯作者：
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