skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Synchronization of Geodesic Acoustic Modes and Magnetic Fluctuations in Toroidal Plasmas

Authors:
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »; ; ; ; ; « less
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1327075
Grant/Contract Number:
FG02-04ER54738
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Physical Review Letters
Additional Journal Information:
Journal Volume: 117; Journal Issue: 14; Related Information: CHORUS Timestamp: 2017-06-24 19:54:21; Journal ID: ISSN 0031-9007
Publisher:
American Physical Society
Country of Publication:
United States
Language:
English

Citation Formats

Zhao, K. J., Nagashima, Y., Diamond, P. H., Dong, J. Q., Itoh, K., Itoh, S. -. I., Yan, L. W., Cheng, J., Fujisawa, A., Inagaki, S., Kosuga, Y., Sasaki, M., Wang, Z. X., Wei, L., Huang, Z. H., Yu, D. L., Hong, W. Y., Li, Q., Ji, X. Q., Song, X. M., Huang, Y., Liu, Yi., Yang, Q. W., Ding, X. T., and Duan, X. R. Synchronization of Geodesic Acoustic Modes and Magnetic Fluctuations in Toroidal Plasmas. United States: N. p., 2016. Web. doi:10.1103/PhysRevLett.117.145002.
Zhao, K. J., Nagashima, Y., Diamond, P. H., Dong, J. Q., Itoh, K., Itoh, S. -. I., Yan, L. W., Cheng, J., Fujisawa, A., Inagaki, S., Kosuga, Y., Sasaki, M., Wang, Z. X., Wei, L., Huang, Z. H., Yu, D. L., Hong, W. Y., Li, Q., Ji, X. Q., Song, X. M., Huang, Y., Liu, Yi., Yang, Q. W., Ding, X. T., & Duan, X. R. Synchronization of Geodesic Acoustic Modes and Magnetic Fluctuations in Toroidal Plasmas. United States. doi:10.1103/PhysRevLett.117.145002.
Zhao, K. J., Nagashima, Y., Diamond, P. H., Dong, J. Q., Itoh, K., Itoh, S. -. I., Yan, L. W., Cheng, J., Fujisawa, A., Inagaki, S., Kosuga, Y., Sasaki, M., Wang, Z. X., Wei, L., Huang, Z. H., Yu, D. L., Hong, W. Y., Li, Q., Ji, X. Q., Song, X. M., Huang, Y., Liu, Yi., Yang, Q. W., Ding, X. T., and Duan, X. R. 2016. "Synchronization of Geodesic Acoustic Modes and Magnetic Fluctuations in Toroidal Plasmas". United States. doi:10.1103/PhysRevLett.117.145002.
@article{osti_1327075,
title = {Synchronization of Geodesic Acoustic Modes and Magnetic Fluctuations in Toroidal Plasmas},
author = {Zhao, K. J. and Nagashima, Y. and Diamond, P. H. and Dong, J. Q. and Itoh, K. and Itoh, S. -. I. and Yan, L. W. and Cheng, J. and Fujisawa, A. and Inagaki, S. and Kosuga, Y. and Sasaki, M. and Wang, Z. X. and Wei, L. and Huang, Z. H. and Yu, D. L. and Hong, W. Y. and Li, Q. and Ji, X. Q. and Song, X. M. and Huang, Y. and Liu, Yi. and Yang, Q. W. and Ding, X. T. and Duan, X. R.},
abstractNote = {},
doi = {10.1103/PhysRevLett.117.145002},
journal = {Physical Review Letters},
number = 14,
volume = 117,
place = {United States},
year = 2016,
month = 9
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1103/PhysRevLett.117.145002

Save / Share:
  • Geodesic Acoustic Modes (GAMs) have been predicted and subsequently observed in many toroidal plasma devices. Bicoherence studies on various devices have suggested three-wave mode coupling processes between GAMs and high frequency turbulence. Thus the parametric coupling of GAMS to drift waves and/or ion temperature gradient(ITG{r_brace} modes is a potential candidate for excitation of these modes. In this paper we discuss the resonant three-wave coupling mechanism for the excitation of GAMs by ITG and finite beta drift waves in homogeneous and inhomogeneous plasmas and compare theoretical predictions with observed characteristics of the GAMs.
  • A set of reduced linear equations for the description of low-frequency perturbations in toroidally rotating plasma in axisymmetric tokamak is derived in the framework of ideal magnetohydrodynamics. The model suitable for the study of global geodesic acoustic modes (GGAMs) is designed. An example of the use of the developed model for derivation of the integral conditions for GGAM existence and of the corresponding dispersion relation is presented. The paper is dedicated to the memory of academician V.D. Shafranov.
  • The geodesic acoustic mode (GAM) is a high frequency branch of zonal flows, which is observed in toroidal plasmas. Because of toroidal curvature effects, density fluctuations are excited, which are investigated with the O-mode correlation reflectometer at TEXTOR. This Letter reports on the poloidal distribution of GAM induced density fluctuation and compares them with theoretical predictions. The influence of the GAM flows on the ambient turbulence is studied, too.
  • The drift kinetic equation is solved for investigation of the plasma response to electromagnetic geodesic acoustic modes. The plasma flow within magnetic surfaces is considered. A perpendicular magnetic perturbation with poloidal number m=2 is created due to the m=2 parallel return current.
  • Strong correlation between high frequency microturbulence and low frequency geodesic acoustic mode (GAM) has been observed in the edge plasmas of the HL-2A tokamak, suggesting possible GAM generation via three wave coupling with turbulence, which is in turn modulated by the GAM. In this work, we use the gyrokinetic toroidal code to study the linear and nonlinear development of the drift instabilities, as well as the generation of the GAM (and low frequency zonal flows) and its interaction with the turbulence for realistic parameters in the edge plasmas of the HL-2A tokamak for the first time. The simulation results indicatemore » that the unstable drift wave drives strong turbulence in the edge plasma of HL-2A. In addition, the generation of the GAM and its interaction with the turbulence are all observed in the nonlinear simulation. The simulation results are in reasonable agreement with the experimental observations.« less