The Microwave Tokamak eXperiment at LLNL was designed to explore the physics of microwave interactions in plasmas using high power millimeter wave sources. We have used 140 GHz power from two sources, a gyrotron capable of ∼ 1MW pulsed, 400 kW CW, and a free electron laser with 100-400 MW pulses of ∼ 10 ns for experiments, with results that we will describe here. Our interests center on non-linear absorption phenomena (FEL) and on heating, transport, and MHD control (FEL and gyrotron) in tokamak plasmas. In the first phase of the FEL experiments we were theoretically in the linear absorption regime, and our plasma transmission experiments gave results consistent with linear theory (with refraction included).
K. I. Thomassen, K. I. Thomassen,
"High power millimeter wave heating in MTX", Proc. SPIE 1576, 16th International Conference on Infrared and Millimeter Waves, 15765N (1 October 1991); doi: 10.1117/12.2297916; https://doi.org/10.1117/12.2297916