Confinement enhancement in ASDEX Upgrade improved H-mode discharges with nitrogen seeding
نویسندگان
چکیده
1 Introduction Tungsten has been studied for 10 years on ASDEX Upgrade as a possible first wall material for fusion reactors [1]. The feasibility and the performance of the advanced scenarios are assessed, in order to deal with the technological challenges of a burning plasma. In particular hybrid scenarios, such as ASDEX Upgrade's improved H-mode discharges, require high heating power, a challenge to the tolerable heat flux on the divertor plates. A significant tungsten inflow from the first wall would lead to performance degradation and, in case of accumulation, to a radiative collapse. A method to control the power load to the divertor is to induce radiative plasma cooling. In this work we analyse the core transport in ASDEX Upgrade improved H-mode discharges with nitrogen seeding [2].
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