Basic divertor operation in ITER-FEAT

The modelling studies being performed for steady state divertor operation of the ITER-FEAT design are summarized. Optimization of the divertor geometry reveals the importance of the proper target shape for a reduction of the peak power loads. A high gas conductance between the divertor legs is also essential for maintaining acceptable conditions in the outer divertor, which receives a higher power loading than the inner divertor. Impurity seeding, which would be necessary if tritium co-deposition concerns precluded the use of carbon as the plasma facing material, can ensure the required high radiation level at acceptable Z(eff), and the divertor performance is not very sensitive to the choice of radiating impurity.