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E. Viezzer, E. Fable, M. Cavedon, F. Laggner, C. Angioni, M. Dunne, R. Dux, M. Bernert, A. Burckhart, R. McDermott, T. Odstrcil, T. Pütterich, F. Ryter, E. Wolfrum, . ASDEX Upgrade Team, -. EUROfusion MST1 Team:
"Ion heat and momentum transport in the edge pedestal of ASDEX Upgrade";
in: "Proc. 42nd EPS Conference on Plasma Physics, Europhys. Conf. Abstracts", Vol. 39E; EPS Conference on Plasma Physics, 2015, ISBN: 2-914771-98-3, S. 11241 - 11244.

Edge localizedmodes (ELMs) aremagnetohydrodynamic instabilities that occur at the plasma
edge of high confinement (H-mode) plasmas. These bursty edge perturbations expel particles
and energy from the pedestal region, leading to a transient degradation of the H-mode transport
barrier. ELMs are thought to be driven by a complex interplay between the edge pressure gradient
Ñp and current density j. The energy exhaust during an ELM (which lasts typically for
1-2ms) can account for up to 30% of the total stored energy in the plasma.
In this paper we present the temporal evolution of the ion and electron profiles during the
ELM cycle. A comparison of the toroidal momentum and thermal energy losses is shown for
a variety of H-mode plasmas with different conditions. Analysis of the ion heat transport at
the plasma edge shows that the ion heat conductivity is close to the neoclassical level in high
collisionality plasmas, while at lower collisionality the ion heat transport is observed to be a
factor of 2 higher in the pedestal region.