Automatic Stabilization of Magnetic Islands Using Radio Frequency Wave Heating and Current Drive*

A nonlinear effect, “RF condensation”, is predicted to facilitate the stabilization of magnetic islands using RF (radio frequency) waves. In particular, it is predicted to provide automatic stabilization of magnetic islands with no need to adjust the aiming of the ray trajectories, with an initially broad RF driven current coalescing in an island when the island grows to sufficient width. Quantitative experimental validation of the theory has thus far been lacking. We discuss some potential opportunities for validating the theory on a contemporary tokamak, focusing particularly on DIII-D.