Conceptual definition of an ICRF system for the Italian DTT

An Italian Divertor Tokamak Test (DTT) facility has been proposed to tackle a major mission of the European roadmap to fusion electricity, i.e. the problem of power exhaust. DTT will rely on an unprecedented amount of additional heating power, including ion-cyclotron resonance frequency (ICRF), to attain a DEMO-relevant power-over-radius ratio crossing the separatrix. This paper reports the status of the ICRF conceptual design, providing the rationale behind main design choices to couple 3 MW to the first DTT plasmafuss (day-1) and up to 10 MW after machine upgrade to full power. The most suitable antenna concepts are identified according to performance documented in literature along with matching schemes able to face fast variation of plasma admittance, and the state-of-the-art of DTT-relevant radiofrequency sources is briefly sketched too. Some preliminary antenna designs are compared on the basis of simulation results, discussing the strengths and weaknesses of each candidate.