Correlation properties of Geodesic Acoustic Modes in the T-10 tokamak

15th Latin American Workshop on Plasma Physics; 21st IAEA TM on Research Using Small Fusion Devices

Melnikov, A.V.^1,2 ; Eliseev, L.G.^1 ; Lysenko, S.E.^1 ; Perfilov, S.V.^1 ; Shelukhin, D.A.^1 ; Vershkov, V.A.^1 ; Zenin, V.N.^1 ; Krupnik, L.I.^3 ; Kharchev, N.K.^4

National Research Centre Kurchatov Institute, Moscow

123182, Russia^1

National Research Nuclear University MEPhI, Moscow

115409, Russia^2

Institute of Plasma Physics, NSC Kharkov Institute of Physics and Technology, Kharkov, Ukraine^3

Institute of General Physics, Russian Academy of Science, Moscow, Russia^4

关键词: Correlation properties;    Density fluctuation;    Electron cyclotron resonance heating;    Electrostatic potentials;    Frequency ranges;    Geodesic acoustic modes;    Heavy ion beam probes;    Higher frequencies;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/591/1/012003/pdf
DOI  :  10.1088/1742-6596/591/1/012003

来源: IOP

【 摘 要 】

Geodesic acoustic mode (GAM) of electrostatic potential and density fluctuations are simultaneously measured by Heavy Ion Beam Probe (HIBP) and Correlation Reflectometry (CR). The regimes with Ohmic and electron cyclotron resonance heating (ECRH) were studied (B = 2.2 T, Ip= 210 - 240 kA, ne= (2.3 - 3.7) × 1019m-3, PEC≤ 0.6 MW). GAMs are more pronounced during ECRH, when the typical frequencies were seen in the narrow band from 22 to 27 kHz for the main peak and 25-30 kHz for the higher frequency satellite peak. The local values of electric potential and density fluctuations show the significant coherency and constant phase shift at GAM frequency range. The existence of the long-distance (one quarter of the torus) correlations of core electric potential and density for GAM implying that GAM is a global mode, was shown for the first time in tokamaks.