Fusion Science and Technology / Volume 51 / Number 2T / February 2007 / Pages 154-159
Technical Paper / Open Magnetic Systems for Plasma Confinement
Nonlinear electromagnetic waves generated due to the injection of high-power electromagnetic waves relating to an electron cyclotron resonance (ECR) are investigated in the GAMMA10 tandem-mirror fusion device and the QT-Upgrade laboratory device. In the GAMMA10 device, an electrostatic wave in the ion-cyclotron range of frequencies is observed around a west barrier region. During the barrier and plug electron cyclotron resonance heating (ECH), the nonlinear electromagnetic waves with the interval of the frequency corresponding to the electrostatic fluctuation are radiated from the plug region. In the QT-Upgrade laboratory device, on the other hand, the injected microwave nonlinearly interacts with an electrostatic drift-wave instability. These results in the GAMMA10 and the QT-Upgrade devices indicate the radiation of the electromagnetic waves originating from the parametric instability.