GYROSHEATH NEAR THE TOKAMAK EDGE

A new model for the structure of the radial electric-field profile in the edge during the high confinement (H mode) is proposed. Charge sepa ration caused by the difference between electron and ion gyromotion, o r more importantly in the tokamak, the banana motion (halo effect) can self-consistently produce an electric dipole moment that causes the s heared radial electric field. The calculated results based on the mode l are consistent with DIII-D [Fusion Technol. 8, 441 (1985)] and Tokam ak Experiment for Technology Oriented Research (TEXTOR) [J. Nucl. Mate r. 122-123, 1124 (1984)] experimental results.