Hybrid H-Mode Scenario with Nitrogen Seeding and Type III ELMs in JET
The performance of the hybrid H-mode regime has been extensively investigated in JET experiments up to bN = 3, toroidal field Bt = 1.7T, with type I ELMs edge conditions. The optimized external current drive sources and stability properties in the plasma core provide a good prospect of achieving a high fusion gain at reduced plasma current for durations up to 2000s in ITER . One of the remaining issues is the problem of erosion of the divertor target plates associated with the type I ELM regime. A possible solution could be to operate with a plasma edge in the type III ELM regime (reduced heat loads) obtained with impurity seeding . In this paper we report on experiments that have recently been performed on JET to investigate the feasibility of an integrated hybrid type III ELM regime with nitrogen seeding.