ITER ECRF Upper Launcher Optimisation Studies

The quasi-optical ECWGB code is used to predict the design requirements and performances of the ITER-ECRF Upper Launcher, that has as its main goal the stabilization of (3,2) and (2,1) neoclassical tearing modes. Detailed calculations are presented here for various ITERFEAT relevant plasma scenarios. The required steering range and the behavior of figures of merit for NTMs stabilization are shown for both the upper and lower row of mirrors, pointing out that larger efficiencies are obtained by launching from the lower row. The effect of the local beam size on the width of the driven current profile is underlined.