Recent results of ICRF heating on jet

During ICRF heating experiments, the new four‐strap A2 antennas on JET have coupled 16.5 MW of power into single null divertor plasmas (Fig. 1). In combined heating experiments a maximum of 32 MW has been achieved by adding 15 MW of hydrogen minority ICRH to 17 MW of neutral beam injection (NBI). This combined heating power is a record for the present campaign and was achieved in a high density, strongly radiating, reactor‐like scenario with ‘grassy’ ELMs. Central electron temperatures close to 15 keV have been obtained with both RF—only and combined heating in ELM—free plasmas which were created with high flux expansion in the divertor region and which were substantially triangular (δ≂0.3). Similar discharges were used to obtain the highest D‐D reactivity in JET with NBI. The addition of hydrogen minority ICRH to these plasmas increases both the reactivity and the H‐factor obtained by comparing the thermal energy content to the ITERH93‐P scaling. RF‐only H‐modes have been produced in plasmas with current...