Phase-locking of Magnetic Islands Diagnosed by ECE-Imaging
Authors: B. Tobias, B.A. Grierson, C.M. Muscatello, X. Ren, C.W. Domier, N.C. Luhmann, Jr., S.E. Zemedkun, T.L. Munsat, and I.G.J. Classen
Abstract: Millimeter-wave imaging diagnostics identify phase-locking and the satisfaction of 3-wave coupling selection criteria amongst multiple magnetic island chains by providing a localized, internal measurement of the 2D power spectral density, S(ω, kpol). In high-confinement tokamak discharges, these interactions impact both plasma rotation and tearing stability. Nonlinear coupling amongst neoclassical tearing modes (NTMs) of different n-number, with islands not satisfying the poloidal mode number selection criterion {m, m ', m − m ' }, contributes to a reduction in core rotation and flow shear in the vicinity of the modes.
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Presented at: the 20th Topical Conference on High-Temperature Plasma Diagnostics, Atlanta, Georgia, June, 2014.
Published in: Review of Scientific Instruments, 85, 11D847 (2014)
DOI:10.1063/1.4892438
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