Recent results obtained during the first part of the JET D-T phase arepresented. Emphasis is placed on conditions carefully set to be similar to thoserequired in ITER. Wall loading changeover from 100% deuterium to 90% tritium wasachieved in about twenty discharges with 100% tritium injection. H mode thresholdpower was found to have inverse isotopic mass dependence whereas there was little massdependence of global energy confinement time in the ELM free or ELMy H mode discharges.Preliminary results are consistent with the gyro-Bohm physics form of global energyconfinement time. This form has a weak negative mass dependence but a stronger densitydependence than the ITERH93-P form. The second harmonic ICRH ITER reference scenario(2ωCT with and without the addition of a small amount of 3He) wasassessed in JET D-T plasmas. High performance combined heating (neutral beam + ICRH)hot ion and optimized shear regime experiments were carried out with only half theinstalled neutral beam power. Nevertheless, internal confinement barriers in theoptimized shear regime were also demonstrated in D-T plasmas.
Bulk ion heating with ICRH in JET DT plasmas