Publication
The ITER ECRH upper port antenna (or launcher) will be used to drive current locally for stabilising the neoclassical tearing mode (NTM)) by depositing mm-wave power inside of the island which forms on the q=3/2 or 2 rational magnetic flux surfaces and control the sawtooth instability by driving current near the q=1 surface. This requires the launcher to be capable of steering the focused beam deposition location across the resonant flux surface over the range where the q=1, 3/2 and 2 surfaces are expected to be found (roughly the outer half of the plasma) [4].