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(TH/P1-02) Angular Momentum Generation: Theory and Recent Experiments

B. Coppi1)
1)Massachusetts Institute of Technology, Cambridge, MA, US

Abstract.  Two of the key elements of the accretion theory of the angular momentum ``generation'' phenomenon in axisymmetric toroidal plasmas are the transfer of angular momentum to the surrounding material wall by plasma modes excited at the edge of the plasma column and the transport of ``negative'' angular momentum toward the center of the plasma column by remnant ion temperature gradient driven modes. The phase velocity of the edge scattering modes is expected to reverse direction in the transition from poor confinement regime, for the ion thermal energy, to good confinement (e.g. H-regime). Consequently the oppositely directed toroidal velocity within the plasma column also reverses. The relationship of this theory to recent experiments that have provided support for it is pointed out. The toroidal analysis of the main elements of the theory, that involve the quasi-linear angular momentum pinch the characteristics of the modes involved, the excited spectrum and the related transport coefficient for the plasma thermal energy, is presented. The inadequacy of the neoclassical transport theory to explain the experimental observations is also pointed out.

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IAEA 2003