Assessment of the Performance of Different Cooling Configurations for the Launcher Mirrors of the ECRH System of the DTT Facility

The launcher mirrors will allow the injection of microwave power from the gyrotrons in the plasma of the Divertor Tokamak Test facility, under construction in Italy. The active cooling of the elliptical M1 (curved and not-steerable) and M2 (flat and steerable) mirrors, both subject to a significant heat load, is investigated in this article. Several cooling solutions are analyzed: a spiral cooling for M1, both in a massive and in a lightened configuration, and also a radial-azimuthal cooling for M2, both in a massive and in a lightened configuration. Figures of merit are computed for the different configurations.