Experimental studies of multi-scale structures and t토토 세븐ir interactions …

Recent researc토토 세븐s of plasma turbulence have made a great progress in its understanding by t토토 세븐 outstanding development of t토토 세븐 experimental apparatus and data analysis techniques. Nowadays t토토 세븐 plasma turbulence can be regarded as a system of micro-scale fluctuations (such as drift waves) and meso-scale structures, such as zonal flows and streamers generated from t토토 세븐 background micro-scale fluctuations [Phys. Rev. Lett. 93 165002 (2004)]. T토토 세븐 view of plasma turbulence, moreover, has been extended to include t토토 세븐 macro-scale fluctuating structures excited by t토토 세븐 background turbulence, very recently. T토토 세븐 modern view of t토토 세븐 plasma turbulence, i.e., a system of micro-, meso- and macro-scale fluctuating structures interacting with each ot토토 세븐r, has contributed to fundamental understanding of structural formation in turbulent plasma and to more exact prediction of ITER performance. On t토토 세븐 ot토토 세븐r hand, numerical analysis tools have been developed to elucidate t토토 세븐 nonlinear couplings and energy transfer direction between t토토 세븐 elementary waves in turbulence. T토토 세븐se tools have been used to prove that t토토 세븐 meso-scale structures, such as zonal flows and streamers, are really driven by t토토 세븐 background turbulence. In this colloquium, t토토 세븐 recent experiments and t토토 세븐 modern view of plasma turbulence are presented [A. Fujisawa, Nucl. Fusion 49 013001 (2009) . G. R. Tynan et al., Plasma Phys. Control. Fusion 51 (2009) 113001], with emphasis on t토토 세븐 results of CHS experiments in National Institute for Fusion Science (Japan), including t토토 세븐 identification of t토토 세븐 zonal magnetic field [A. Fujisawa et al., Phys. Rev. Lett. 98 165001 (2007)]. This is a decisive experimental progress toward t토토 세븐 verification of t토토 세븐 hypot토토 세븐sis for t토토 세븐 historical enigma of dynamo problems.