Operation and development plans of JET

The main objective of the Joint European Torus (JET) experiment is to obtain substantial alpha heating of a D+T plasma in this tokamak device. To reach this goal, the experimental programme is laid down in four phases, and in each phase the machine improvements and modifications required for the following phase are implemented and tested. JET has been operational since June 1983 and since January 1985 experimental work has been carried out in two shifts (16 hours/day). The key experimental results, in the Ohmic Heating conditions, exceeded expectations, allowing a fusion parameter of (n/sub iD/tau/sub E/T/sub i/)=0.5 10/sup 20/m/sup -3/skeV to be reached. Preliminary experiments with ICRH heating have produced ion temperatures up to 4 keV using less than 20% (≤5 MW) of the additional heating power which will be eventually available