Zonal flows in the geodesic acoustic mode frequency range in the JIPP T-IIU tokamak plasmas

被引:91
作者
Hamada, Y [1 ]
Nishizawa, A [1 ]
Ido, T [1 ]
Watari, T [1 ]
Kojima, M [1 ]
Kawasumi, Y [1 ]
Narihara, K [1 ]
Toi, K [1 ]
机构
[1] Natl Inst Fus Sci, Toki 5095292, Japan
关键词
D O I
10.1088/0029-5515/45/2/002
中图分类号
O35 [流体力学]; O53 [等离子体物理学];
学科分类号
070204 ; 080103 ; 080704 ;
摘要
Large potential oscillations were detected in JIPPT-IIU tokamak plasmas in a wide range of plasma cross-sections in measurements using a multi-sample-volume heavy ion beam probe. These oscillations have large amplitudes reaching a few hundreds of volts and their frequencies are in the range of the geodesic acoustic mode (GAM). They are found over a wide range of plasma cross-sections and commonly have m = 0 structures. As they were Fourier analysed, it was found that the central frequency is higher in the core of the plasma and lower in the edge of the plasma. These observations agree with the properties of theoretically predicted GAM oscillations. It was also found that the frequency spectrum is peaked in the core and broad in the edge, which may have something to do with damping mechanisms of the GAM. The phase relation between the density and the electric field fluctuations was studied extensively in terms of the cross-correlation function. The level of the density fluctuation was low as it should be,, and the expected 90 degrees phase difference was found in a limited radial domain.
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页码:81 / 88
页数:8
相关论文
共 30 条
[11]   Fast potential change during sawteeth in JIPP T-IIU tokamak plasmas [J].
Hamada, Y ;
Nishizawa, A ;
Kawasumi, Y ;
Kawahata, K ;
Itoh, K ;
Ejiri, A ;
Toi, K ;
Narihara, K ;
Sato, K ;
Seki, T ;
Iguchi, H ;
Fujisawa, A ;
Adachi, K ;
Hidekuma, S ;
Hirokura, S ;
Ida, K ;
Kojima, M ;
Koong, J ;
Kumazawa, R ;
Kuramoto, H ;
Liang, R ;
Minami, T ;
Sakakita, H ;
Sasao, M ;
Sato, KN ;
Tsuzuki, T ;
Xu, J ;
Yamada, I ;
Watari, T .
NUCLEAR FUSION, 1996, 36 (04) :515-520
[12]   DEVELOPMENTS IN THE GYROFLUID APPROACH TO TOKAMAK TURBULENCE SIMULATIONS [J].
HAMMETT, GW ;
BEER, MA ;
DORLAND, W ;
COWLEY, SC ;
SMITH, SA .
PLASMA PHYSICS AND CONTROLLED FUSION, 1993, 35 (08) :973-985
[13]   SELF-ORGANIZATION OF ELECTROSTATIC TURBULENCE IN A CYLINDRICAL PLASMA [J].
HASEGAWA, A ;
WAKATANI, M .
PHYSICAL REVIEW LETTERS, 1987, 59 (14) :1581-1584
[14]   POLOIDAL SPIN-UP OF TOKAMAK PLASMAS FROM POLOIDAL ASYMMETRY OF PARTICLE AND MOMENTUM SOURCES [J].
HASSAM, AB ;
ANTONSEN, TM .
PHYSICS OF PLASMAS, 1994, 1 (02) :337-344
[15]   A DIRECT MEASUREMENT OF PLASMA SPACE POTENTIAL [J].
JOBES, FC ;
HICKOK, RL .
NUCLEAR FUSION, 1970, 10 (02) :195-&
[16]   Turbulent transport reduction by zonal flows: Massively parallel simulations [J].
Lin, Z ;
Hahm, TS ;
Lee, WW ;
Tang, WM ;
White, RB .
SCIENCE, 1998, 281 (5384) :1835-1837
[17]   Observation and characterization of radially sheared zonal flows in DIII-D [J].
McKee, R ;
Fonck, RJ ;
Jakubowski, M ;
Burrell, KH ;
Hallatschek, K ;
Moyer, RA ;
Nevins, W ;
Rudakov, DL ;
Xu, X .
PLASMA PHYSICS AND CONTROLLED FUSION, 2003, 45 :A477-A485
[18]   On the detection of Reynolds stress as a driving and damping mechanism of geodesic acoustic modes and zonal flows [J].
Ramisch, M ;
Stroth, U ;
Niedner, S ;
Scott, B .
NEW JOURNAL OF PHYSICS, 2003, 5 :12.1-12.11
[19]   EVIDENCE FOR CONFINEMENT IMPROVEMENT BY VELOCITY-SHEAR SUPPRESSION OF EDGE TURBULENCE [J].
RITZ, CP ;
LIN, H ;
RHODES, TL ;
WOOTTON, AJ .
PHYSICAL REVIEW LETTERS, 1990, 65 (20) :2543-2546
[20]   Generation and stability of zonal flows in ion-temperature-gradient mode turbulence [J].
Rogers, BN ;
Dorland, W ;
Kotschenreuther, M .
PHYSICAL REVIEW LETTERS, 2000, 85 (25) :5336-5339