The JAERI heating activities: Tokamak experiments and R and D works

Heating results on JFT-2 and DIVA tokamaks at JAERI are presented. Also reported are related research and developments works for the next stage tokamak JT-60. In the JFT-2 lower hybrid heating we demonstrated ion heating efficiency of 50% and current generation of 110 A/kW including suprathermal electrons. High efficiency majority heating efficiency of 80% was attained in DIVA ICRF heating experiment. With the neutral beam injection power up to 1.2 MW, the observed maximum beta at the axis is 7% and 10%; the average beta is 2.6% and 3% due to thermal component and including beam component, respectively. No adverse effect on plasma confinement is observed. We can now extract hydrogen beams of 75 keV, 35 A, 0.1 sec and 75 keV, 6 A, 6 sec. Development of a 1.1 MW-10 sec klystron at 2.0 GHz will be started in October, 1980