This title appears in the Scientific Report : 2020 

Peculiarity of highly radiating multi-impurity seeded H -mode plasmas on JET with ITER-like wall
Huber, A. (Corresponding author)
Wischmeier, M. / Bernert, M. / Wiesen, S. / Glöggler, S. / Aleiferis, S. / Brezinsek, S. / Calabro, G. / Carvalho, P. / Huber, V. / Sergienko, G. / Solano, E. R. / Giroud, C. / Groth, M. / Jachmich, S. / Linsmeier, Ch / Matthews, G. F. / Meigs, A. G. / Mertens, Ph / Sertoli, M. / Silburn, S. / Telesca, G.
Plasmaphysik; IEK-4
Physica scripta, T171 (2020) S. 014055 -
Stockholm The Royal Swedish Academy of Sciences 2020
Journal Article
Published on 2020-03-16. Available in OpenAccess from 2021-03-16.
Published on 2020-03-16. Available in OpenAccess from 2021-03-16.
Please use the identifier: in citations.
Please use the identifier: in citations.
On JET with fully metallic first wall, highly radiative conditions with N2, Ne and Ar as well as their mixture as radiators are approached in high density H-mode plasmas. The confinement increases from H 98(y,2) = 0.65 in unseeded pulses with γ rad ~ 30% to a value of H 98(y,2) = 0.75 at γ rad ~ 50% with N2 injection. A degradation of the pedestal profile is compensated by steeper core n e and T e profiles. Further increase of γ rad with increase of the N2 seeding rate leads to a moderate confinement degradation which can be avoided by applying of combined impurity seeding. The enhancement of the plasma performance for the radiation fractions beyond 55% with the maximum value of H 98(y,2) = 0.78 is reached with combined N2 + Ne and N2 + Ar impurity injections. The observed intense, strongly localized radiation at the X-point inside the confined plasma in the scenarios with the highest radiated power fraction is interlinked to complete divertor detachment. In the JET-ILW, the X-point radiation is stable, reproducible and reversible.