CHANGE OF TRANSPORT AT L-MODE AND H-MODE TRANSITION

A new refined model of the L-mode and H-mode transition in tokamaks is presented based on the bifurcation of the radial electric field, Er, near the edge. The radial gradient of Er is newly introduced to explain the sudden change of fluctuations as well as plasma fluxes at the onset of transition. This nodel predicts that the L- to H- mode transition is associated with the decrease of dEr/ dr causing reduction of particle and energy fluxes at the critical gradient. © 1990, THE PHYSICAL SOCIETY OF JAPAN. All rights reserved.