TY - JOUR
T1 - Overview of ASDEX Upgrade results
JF - Nuclear Fusion
Y1 - 2011
A1 - Kallenbach, A.
A1 - Adamek, J.
A1 - Aho-Mantila, L.
A1 - Akaslompolo, S.
A1 - Angioni, C.
A1 - Atanasiu, C. V.
A1 - Balden, M.
A1 - Behler, K.
A1 - Belonohy, E.
A1 - Bergmann, A.
A1 - Bernert, M.
A1 - Bilato, R.
A1 - Bobkov, V.
A1 - Boom, J.
A1 - Bottino, A.
A1 - Braun, F.
A1 - Brudgam, M.
A1 - Buhler, A.
A1 - Burckhart, A.
A1 - Chankin, A.
A1 - Classen, I.G.J.
A1 - Conway, G. D.
A1 - Coster, D. P.
A1 - de Marne, P.
A1 - D'Inca, R.
A1 - Drube, R.
A1 - Dux, R.
A1 - Eich, T.
A1 - Endstrasser, N.
A1 - Engelhardt, K.
A1 - Esposito, B.
A1 - Fable, E.
A1 - Fahrbach, H. U.
A1 - Fattorini, L.
A1 - Fischer, R.
A1 - Flaws, A.
A1 - Funfgelder, H.
A1 - Fuchs, J. C.
A1 - Gal, K.
A1 - Munoz, M. G.
A1 - Geiger, B.
A1 - Adamov, M. G.
A1 - Giannone, L.
A1 - Giroud, C.
A1 - Gorler, T.
A1 - da Graca, S.
A1 - Greuner, H.
A1 - Gruber, O.
A1 - Gude, A.
A1 - Gunter, S.
A1 - Haas, G.
A1 - Hakola, A. H.
A1 - Hangan, D.
A1 - Happel, T.
A1 - Hauff, T.
A1 - Heinemann, B.
A1 - Herrmann, A.
A1 - Hicks, N.
A1 - Hobirk, J.
A1 - Hohnle, H.
A1 - Holzl, M.
A1 - Hopf, C.
A1 - Horton, L.
A1 - Huart, M.
A1 - Igochine, V.
A1 - Ionita, C.
A1 - Janzer, A.
A1 - Jenko, F.
A1 - Kasemann, C. P.
A1 - Kalvin, S.
A1 - Kardaun, O.
A1 - Kaufmann, M.
A1 - Kirk, A.
A1 - Klingshirn, H. J.
A1 - Kocan, M.
A1 - Kocsis, G.
A1 - Kollotzek, H.
A1 - Konz, C.
A1 - Koslowski, R.
A1 - Krieger, K.
A1 - Kurki-Suonio, T.
A1 - Kurzan, B.
A1 - Lackner, K.
A1 - Lang, P. T.
A1 - Lauber, P.
A1 - Laux, M.
A1 - Leipold, F.
A1 - Leuterer, F.
A1 - Lohs, A.
A1 - N C Luhmann Jr.
A1 - Lunt, T.
A1 - Lyssoivan, A.
A1 - Maier, H.
A1 - Maggi, C.
A1 - Mank, K.
A1 - Manso, M. E.
A1 - Maraschek, M.
A1 - Martin, P.
A1 - Mayer, M.
A1 - McCarthy, P. J.
A1 - McDermott, R.
A1 - Meister, H.
A1 - Menchero, L.
A1 - Meo, F.
A1 - Merkel, P.
A1 - Merkel, R.
A1 - Mertens, V.
A1 - Merz, F.
A1 - Mlynek, A.
A1 - Monaco, F.
A1 - Muller, H. W.
A1 - Munich, M.
A1 - Murmann, H.
A1 - Neu, G.
A1 - Neu, R.
A1 - Nold, B.
A1 - Noterdaeme, J. M.
A1 - Park, H. K.
A1 - Pautasso, G.
A1 - Pereverzev, G.
A1 - Podoba, Y.
A1 - Pompon, F.
A1 - Poli, E.
A1 - Polochiy, K.
A1 - Potzel, S.
A1 - Prechtl, M.
A1 - M. J. Pueschel
A1 - Putterich, T.
A1 - Rathgeber, S. K.
A1 - Raupp, G.
A1 - Reich, M.
A1 - Reiter, B.
A1 - Ribeiro, T.
A1 - Riedl, R.
A1 - Rohde, V.
A1 - Roth, J.
A1 - Rott, M.
A1 - Ryter, F.
A1 - Sandmann, W.
A1 - Santos, J.
A1 - Sassenberg, K.
A1 - Sauter, P.
A1 - Scarabosio, A.
A1 - Schall, G.
A1 - Schmid, K.
A1 - Schneider, P. A.
A1 - Schneider, W.
A1 - Schramm, G.
A1 - Schrittwieser, R.
A1 - Schweinzer, J.
A1 - Scott, B.
A1 - Sempf, M.
A1 - Serra, F.
A1 - Sertoli, M.
A1 - Siccinio, M.
A1 - Sigalov, A.
A1 - Silva, A.
A1 - Sips, A.C.C.
A1 - Sommer, F.
A1 - Stabler, A.
A1 - Stober, J.
A1 - Streibl, B.
A1 - Strumberger, E.
A1 - Sugiyama, K.
A1 - Suttrop, W.
A1 - Szepesi, T.
A1 - Tardini, G.
A1 - Tichmann, C.
A1 - Told, D.
A1 - Treutterer, W.
A1 - Urso, L.
A1 - Varela, P.
A1 - Vincente, J.
A1 - Vianello, N.
A1 - Vierle, T.
A1 - Viezzer, E.
A1 - Vorpahl, C.
A1 - Wagner, D.
A1 - Weller, A.
A1 - Wenninger, R.
A1 - Wieland, B.
A1 - Wigger, C.
A1 - Willensdorfer, M.
A1 - Wischmeier, M.
A1 - Wolfrum, E.
A1 - Wursching, E.
A1 - Yadikin, D.
A1 - Yu, Q.
A1 - Zammuto, I.
A1 - Zasche, D.
A1 - Zehetbauer, T.
A1 - Zhang, Y.
A1 - Zilker, M.
A1 - Zohm, H.
KW - PHYSICS
KW - REFLECTOMETRY
KW - TOKAMAK
AB - The ASDEX Upgrade programme is directed towards physics input to critical elements of the ITER design and the preparation of ITER operation, as well as addressing physics issues for a future DEMO design. After the finalization of the tungsten coating of the plasma facing components, the re-availability of all flywheel-generators allowed high-power operation with up to 20 MW heating power at I(p) up to 1.2 MA. Implementation of alternative ECRH schemes (140 GHz O2- and X3-mode) facilitated central heating above n(e) = 1.2 x 10(20) m(-3) and low q(95) operation at B(t) = 1.8 T. Central O2-mode heating was successfully used in high P/R discharges with 20 MW total heating power and divertor load control with nitrogen seeding. Improved energy confinement is obtained with nitrogen seeding both for type-I and type-III ELMy conditions. The main contributor is increased plasma temperature, no significant changes in the density profile have been observed. This behaviour may be explained by higher pedestal temperatures caused by ion dilution in combination with a pressure limited pedestal and hollow nitrogen profiles. Core particle transport simulations with gyrokinetic calculations have been benchmarked by dedicated discharges using variations of the ECRH deposition location. The reaction of normalized electron density gradients to variations of temperature gradients and the T(e)/T(i) ratio could be well reproduced. Doppler reflectometry studies at the L-H transition allowed the disentanglement of the interplay between the oscillatory geodesic acoustic modes, turbulent fluctuations and the mean equilibrium E x B flow in the edge negative E(r) well region just inside the separatrix. Improved pedestal diagnostics revealed also a refined picture of the pedestal transport in the fully developed H-mode type-I ELM cycle. Impurity ion transport turned out to be neoclassical in between ELMs. Electron and energy transport remain anomalous, but exhibit different recovery time scales after an ELM. After recovery of the pre-ELM profiles, strong fluctuations develop in the gradients of n(e) and T(e). The occurrence of the next ELM cannot be explained by the local current diffusion time scale, since this turns out to be too short. Fast ion losses induced by shear Alfven eigenmodes have been investigated by time-resolved energy and pitch angle measurements. This allowed the separation of the convective and diffusive loss mechanisms.
VL - 51
SN - 0029-5515
IS - 9
N1 - ISI Document Delivery No.: 818DPTimes Cited: 1Cited Reference Count: 45SI
U1 - FP
U2 - PDG
U5 - a193177a90d5b600862ca1e40bcc67af
ER -
TY - JOUR
T1 - ELM pacing investigations at JET with the new pellet launcher
JF - Nuclear Fusion
Y1 - 2011
A1 - Lang, P. T.
A1 - Alonso, A.
A1 - Alper, B.
A1 - Belonohy, E.
A1 - Boboc, A.
A1 - Devaux, S.
A1 - Eich, T.
A1 - Frigione, D.
A1 - Gal, K.
A1 - Garzotti, L.
A1 - Geraud, A.
A1 - Kocsis, G.
A1 - Kochl, F.
A1 - Lackner, K.
A1 - Loarte, A.
A1 - Lomas, P. J.
A1 - Maraschek, M.
A1 - Muller, H. W.
A1 - Neu, R.
A1 - Neuhauser, J.
A1 - Petravich, G.
A1 - Saibene, G.
A1 - Schweinzer, J.
A1 - Thomsen, H.
A1 - Tsalas, M.
A1 - Wenninger, R.
A1 - Zohm, H.
KW - ASDEX UPGRADE
KW - ENERGY
KW - INJECTION
KW - ITER
KW - LOSSES
KW - MODE
AB - A new pellet injection system was installed at JET designed for both fuelling and ELM pacing. The purpose of the pacing section was to validate pellet ELM pacing as a suitable tool for ELM mitigation in ITER. Pellet pacing was confirmed at the large size scale of JET. The dynamics of triggered ELMs was investigated with respect to their spontaneous counterparts. Triggered ELMs show features also typical for spontaneous ELMs in several operational regimes. Since none of these regimes was unsettled by the pellets this is a strong hint for compatibility with other plasma control tools. Observations and modelling results indicate the ELM triggering occurs by the evolution of the pellet ablation plasmoid into the first ELM filament followed by a poloidal spread of the instability. An ELM obviously can be forced by a pellet due to the strong local perturbation imposed already under unusual onset conditions but then evolves like any ELM typical for the corresponding plasma regime. For tool optimization the pellet mass and hence the convective confinement losses imposed have to be minimized. In our experiments, a lower mass threshold was observed for the first time. It has been found that to reliably trigger an ELM the pellet needs to be sufficiently large (and fast) to penetrate close to the pedestal top. Recent investigations are clear steps forward to validate the pellet pacing approach for ITER.

VL - 51
SN - 0029-5515
IS - 3
N1 - ISI Document Delivery No.: 729AETimes Cited: 4Cited Reference Count: 38
U1 - FP

U2 - PDG

U5 - 506bca96c5637433dac75b877a0bcc14
ER -