[Zurück]

M. Beurskens, M. Dunne, L. Frassinetti, M. Bernert, M. Cavedon, R. Fischer, A. Järvinen, A. Kallenbach, F. Laggner, R. McDermott, G. Tardini, E. Viezzer, E. Wolfrum, . ASDEX Upgrade Team, -. EUROfusion MST1 Team:
"The role of carbon on the H-mode con_finement in ASDEX Upgrade with a metal wall";
in: "Proc. 42nd EPS Conference on Plasma Physics, Europhys. Conf. Abstracts", EPS Conference on Plasma Physics, 2015, ISBN: 2-914771-98-3, S. 11021 - 11024.

Future fusion devices such as ITER and DEMO will have metal plasma facing wall
components. This is because the conventional use of carbon as a first wall material is
prohibited due to its high tritium retention properties. Seeding light impurities (like N2) is
needed to protect plasma facing components from steady state heat loads. An unexpected
beneficial effect of this recipe is an improvement of confinement stemming from the pedestal
region and resulting in confinement quality previously observed often only in carbon devices
[1, 2, 3]. This observation raises the question as to whether nitrogen seeding in metal devices
substitutes the presence of carbon as an intrinsic impurity, and which physics mechanisms are
at play in the confinement improvement.