WARM-ION DRIFT ALFVEN TURBULENCE AND THE L-H TRANSITION

Computations of fluid drift turbulence treating ions and electrons on equal footing, including both temperatures, are conducted in a model t oroidal geometry. The resulting 'ion mixing mode' turbulence bears fea tures of both electron drift-Alfven and ion temperature gradient turbu lence, and nonlinear sensitivity to the relative strengths of the dens ity and temperature gradients provides a possible route to the bifurca tion needed for the L-H transition.