Potential of the ITER electron cyclotron equatorial launcher for heating and current drive at nominal and reduced fields

Electron cyclotron (EC) heating and current drive (HCD), at 170 GHz, 20 MW, is one of the heating systems foreseen to assist and sustain the development of various ITER scenarios since the early phase of ITER. It is usually assumed that EC is efficient only at magnetic fields operating around full field (5.3 T) and half field (2.65 T), and most of the analyses presented so far have focused on the ECRH&CD performances at flat-top. Here, the EC capabilities are investigated for different plasma parameters corresponding to different phases of the ITER plasma discharge, from current ramp-up up to burn, and for a wide range of magnetic fields, focusing in particular on the EC potential for heating and for L- to H-mode assist. It is found that the EC system can contribute to a wide range of heating scenarios during the ramp-up of the magnetic field, significantly increasing the applicable range as a function of magnetic field as compared with traditional views.

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