Wave phenomena in the scrape-off layer of TCA during Alfven wave heating

Extensive wave studies in the scrape-off layer of the TCA tokamak have been performed during Alfven wave heating. Using Langmuir probes and correlation techniques, it was found that the rf antennae excite waves at the driving rf frequency and that various coherent nonlinear interactions are present. Low frequency turbulence is strongly affected by the presence of rf to the extent that the drift wave velocity can reverse direction during Alfven wave heating. (orig.)