학술논문
Bicoherence analysis of geodesic acoustic modes in the Tuman-3M and Globus-M Tokamaks.
Document Type
Article
Author
Source
Subject
*COHERENCE (Nuclear physics)
*GEODESIC flows
*ACOUSTIC models
*TOKAMAKS
*ACQUISITION of data
*PLASMA flow
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Language
ISSN
1063-7850
Abstract
We present the results of a comparative investigation of geodesic acoustic modes (GAMs) by the method of bicoherence analysis in tokamaks (Tuman-3M and Globus-M) with different aspect ratios. The obtained data provide indirect evidence of the mutual influence of GAMs and background turbulence of tokamak plasma. The cross-bicoherence spectra were calculated using the signals of Doppler reflectometers and temporal dependences of the velocity of plasma rotation in the electric field of GAMs. The level of bicoherence in both tokamaks increases before transition to the H-mode and then decays down to the noise level in the H-mode. [ABSTRACT FROM AUTHOR]