<i>H</i>mode observed in the JFT-2M tokamak with edge heating by electron cyclotron waves

Abstract

The H mode is observed by the edge heating of a tokamak plasma solely by the electron cyclotron heating with the wave cutoff region in the plasma core. Threshold power for the H-mode transition can be as low as 120 kW, which is the lowest threshold power observed in spite of the peripheral power deposition. These experimental results show clearly that the H mode can be produced without additional heating of the plasma core, and provide direct confirmation that the H-mode mechanism is closely related to an increase in the plasma edge electron temperature.