Observation of fluctuationdriven particle flux reduction by lowfrequency zonal flow in a linear magnetized plasma
Abstract
Lowfrequency zonal flow (ZF) has been observed in a linear magnetic plasma device, exhibiting significant intermittency. Using the conditional analysis method, a timeaveraged fluctuationinduced particle flux was observed to consistently decrease as ZF increased in amplitude. A dominant fraction of the flux, which is driven by driftwave harmonics, is reversely modulated by ZF in the time domain. Spectra of the flux, together with each of the related turbulence properties, are estimated subject to two conditions, i.e., when potential fluctuation series represents a strong ZF intermittency or a very weak ZF component. Comparison of frequencydomain results demonstrates that ZF reduces the crossfield particle transport primarily by suppressing the density fluctuation as well as decorrelating density and potential fluctuations.
 Authors:
 CAS Laboratory of Geospace Environment, Department of Modern Physics, University of Science and Technology of China, Hefei 230026 (China)
 (China)
 Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China)
 Publication Date:
 OSTI Identifier:
 22407992
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 1; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; AMPLITUDES; DENSITY; FLUCTUATIONS; HARMONICS; MAGNETIZATION; PARTICLES; PLASMA; POTENTIALS; SPECTRA; TURBULENCE; WAVE PROPAGATION
Citation Formats
Chen, R., Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, Xie, J. L., Email: jlxie@ustc.edu.cn, Yu, C. X., Liu, A. D., Lan, T., Li, H., Liu, W. D., Zhang, S. B., Kong, D. F., and Hu, G. H. Observation of fluctuationdriven particle flux reduction by lowfrequency zonal flow in a linear magnetized plasma. United States: N. p., 2015.
Web. doi:10.1063/1.4905860.
Chen, R., Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, Xie, J. L., Email: jlxie@ustc.edu.cn, Yu, C. X., Liu, A. D., Lan, T., Li, H., Liu, W. D., Zhang, S. B., Kong, D. F., & Hu, G. H. Observation of fluctuationdriven particle flux reduction by lowfrequency zonal flow in a linear magnetized plasma. United States. doi:10.1063/1.4905860.
Chen, R., Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, Xie, J. L., Email: jlxie@ustc.edu.cn, Yu, C. X., Liu, A. D., Lan, T., Li, H., Liu, W. D., Zhang, S. B., Kong, D. F., and Hu, G. H. 2015.
"Observation of fluctuationdriven particle flux reduction by lowfrequency zonal flow in a linear magnetized plasma". United States.
doi:10.1063/1.4905860.
@article{osti_22407992,
title = {Observation of fluctuationdriven particle flux reduction by lowfrequency zonal flow in a linear magnetized plasma},
author = {Chen, R. and Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 and Xie, J. L., Email: jlxie@ustc.edu.cn and Yu, C. X. and Liu, A. D. and Lan, T. and Li, H. and Liu, W. D. and Zhang, S. B. and Kong, D. F. and Hu, G. H.},
abstractNote = {Lowfrequency zonal flow (ZF) has been observed in a linear magnetic plasma device, exhibiting significant intermittency. Using the conditional analysis method, a timeaveraged fluctuationinduced particle flux was observed to consistently decrease as ZF increased in amplitude. A dominant fraction of the flux, which is driven by driftwave harmonics, is reversely modulated by ZF in the time domain. Spectra of the flux, together with each of the related turbulence properties, are estimated subject to two conditions, i.e., when potential fluctuation series represents a strong ZF intermittency or a very weak ZF component. Comparison of frequencydomain results demonstrates that ZF reduces the crossfield particle transport primarily by suppressing the density fluctuation as well as decorrelating density and potential fluctuations.},
doi = {10.1063/1.4905860},
journal = {Physics of Plasmas},
number = 1,
volume = 22,
place = {United States},
year = 2015,
month = 1
}

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