THE EVIDENCE FOR NONLOCAL TRANSPORT IN THE TEXAS-EXPERIMENTAL-TOKAMAK

The electron temperature response of a tokamak to rapid edge cooling h as characteristics difficult to reconcile with local transport analysi s. The initial observations in the Texas Experimental Tokamak [K. W. G entle, Nucl. Tech. Fusion 1, 479 (1981)] have been extended to a wider range of plasma and perturbation parameters, including auxiliary heat ing, and the associated turbulence changes have been measured across t he plasma radius. The fast edge temperature drops and core temperature increases are quantified by more extensive analysis. A perturbation c omplementary to edge cooling, edge heating by a fast current ramp, evo kes a completely complementary plasma response. (C) 1997 American Inst itute of Physics.