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1. Overview of ASDEX upgrade results in view of ITER and DEMO

Author

H. Zohm, E. Alessi, C. Angioni, N. Arden, V. Artigues, M. Astrain, O. Asunta, M. Balden, V. Bandaru, A. Banon Navarro, M. Bauer, A. Bergmann, M. Bergmann, J. Bernardo, M. Bernert, A. Biancalani, R. Bielajew, R. Bilato, G. Birkenmeier, T. Blanken, V. Bobkov, A. Bock, L. Bock, T. Body, T. Bolzonella, N. Bonanomi, A. Bortolon, B. Böswirth, C. Bottereau, A. Bottino, H. van den Brand, M. Brenzke, S. Brezinsek, D. Brida, F. Brochard, J. Buchanan, A. Buhler, A. Burckhart, Y. Camenen, B. Cannas, P. Cano Megías, D. Carlton, M. Carr, P. Carvalho, C. Castaldo, A. Castillo Castillo, A. Cathey, M. Cavedon, C. Cazzaniga, C. Challis, A. Chankin, A. Chomiczewska, C. Cianfarani, F. Clairet, S. Coda, R. Coelho, J.W. Coenen, L. Colas, G. Conway, S. Costea, D. Coster, T. Cote, A.J. Creely, G. Croci, D.J. Cruz Zabala, G. Cseh, I. Cziegler, O. D’Arcangelo, A. Dal Molin, P. David, C. Day, M. de Baar, P. de Marné, R. Delogu, P. Denner, A. Di Siena, M. Dibon, J.J. Dominguez-Palacios Durán, D. Dunai, M. Dreval, M. Dunne, B.P. Duval, R. Dux, T. Eich, S. Elgeti, A. Encheva, B. Esposito, E. Fable, M. Faitsch, D. Fajardo Jimenez, U. Fantz, M. Farnik, H. Faugel, F. Felici, O. Ficker, A. Figueredo, R. Fischer, O. Ford, L. Frassinetti, M. Fröschle, G. Fuchert, J.C. Fuchs, H. Fünfgelder, S. Futatani, K. Galazka, J. Galdon-Quiroga, D. Gallart Escolà, A. Gallo, Y. Gao, S. Garavaglia, M. Garcia Muñoz, B. Geiger, L. Giannone, S. Gibson, L. Gil, E. Giovannozzi, I. Girka, O. Girka, T. Gleiter, S. Glöggler, M. Gobbin, J.C. Gonzalez, J. Gonzalez Martin, T. Goodman, G. Gorini, T. Görler, D. Gradic, G. Granucci, A. Gräter, G. Grenfell, H. Greuner, M. Griener, M. Groth, O. Grover, A. Gude, L. Guimarais, S. Günter, D. Hachmeister, A.H. Hakola, C. Ham, T. Happel, N. den Harder, G. Harrer, J. Harrison, V. Hauer, T. Hayward-Schneider, B. Heinemann, P. Heinrich, T. Hellsten, S. Henderson, P. Hennequin, M. Herschel, S. Heuraux, A. Herrmann, E. Heyn, F. Hitzler, J. Hobirk, K. Höfler, S. Hörmann, J.H. Holm, M. Hölzl, C. Hopf, L. Horvath, T. Höschen, A. Houben, A. Hubbard, A. Huber, K. Hunger, V. Igochine, M. Iliasova, J. Illerhaus, K. Insulander Björk, C. Ionita-Schrittwieser, I. Ivanova-Stanik, S. Jachmich, W. Jacob, N. Jaksic, A. Jansen van Vuuren, F. Jaulmes, F. Jenko, T. Jensen, E. Joffrin, A. Kallenbach, J. Kalis, A. Kappatou, J. Karhunen, C.-P. Käsemann, S. Kasilov, Y. Kazakov, A. Kendl, W. Kernbichler, E. Khilkevitch, M. Kircher, A. Kirk, S. Kjer Hansen, V. Klevarova, F. Klossek, G. Kocsis, M. Koleva, M. Komm, M. Kong, A. Krämer-Flecken, M. Krause, I. Krebs, A. Kreuzeder, K. Krieger, O. Kudlacek, D. Kulla, T. Kurki-Suonio, B. Kurzan, B. Labit, K. Lackner, F. Laggner, A. Lahtinen, P. Lainer, P.T. Lang, P. Lauber, M. Lehnen, L. Leppin, E. Lerche, N. Leuthold, L. Li, J. Likonen, O. Linder, H. Lindl, B. Lipschultz, Y. Liu, Z. Lu, T. Luda Di Cortemiglia, N.C. Luhmann, T. Lunt, A. Lyssoivan, T. Maceina, J. Madsen, A. Magnanimo, H. Maier, J. Mailloux, R. Maingi, O. Maj, E. Maljaars, V. Maquet, A. Mancini, A. Manhard, P. Mantica, M. Mantsinen, P. Manz, M. Maraschek, C. Marchetto, M. Markl, L. Marrelli, P. Martin, F. Matos, M. Mayer, P.J. McCarthy, R. McDermott, G. Meng, R. Merkel, A. Merle, H. Meyer, M. Michelini, D. Milanesio, V. Mitterauer, P. Molina Cabrera, M. Muraca, F. Nabais, V. Naulin, R. Nazikian, R.D. Nem, R. Neu, A.H. Nielsen, S.K. Nielsen, T. Nishizawa, M. Nocente, I. Novikau, S. Nowak, R. Ochoukov, J. Olsen, P. Oyola, O. Pan, G. Papp, A. Pau, G. Pautasso, C. Paz-Soldan, M. Peglau, E. Peluso, P. Petersson, C. Piron, U. Plank, B. Plaum, B. Plöckl, V. Plyusnin, G. Pokol, E. Poli, A. Popa, L. Porte, J. Puchmayr, T. Pütterich, L. Radovanovic, M. Ramisch, J. Rasmussen, G. Ratta, S. Ratynskaia, G. Raupp, A. Redl, D. Réfy, M. Reich, F. Reimold, D. Reiser, M. Reisner, D. Reiter, B. Rettino, T. Ribeiro, D. Ricci, R. Riedl, J. Riesch, J.F. Rivero Rodriguez, G. Rocchi, P. Rodriguez-Fernandez, V. Rohde, G. Ronchi, M. Rott, M. Rubel, D.A. Ryan, F. Ryter, S. Saarelma, M. Salewski, A. Salmi, O. Samoylov, L. Sanchis Sanchez, J. Santos, O. Sauter, G. Schall, A. Schlüter, J. Scholte, K. Schmid, O. Schmitz, P.A. Schneider, R. Schrittwieser, M. Schubert, C. Schuster, N. Schwarz, T. Schwarz-Selinger, J. Schweinzer, F. Sciortino, O. Seibold-Benjak, A. Shabbir, A. Shalpegin, S. Sharapov, U. Sheikh, A. Shevelev, G. Sias, M. Siccinio, B. Sieglin, A. Sigalov, A. Silva, C. Silva, D. Silvagni, J. Simpson, S. Sipilä, A. Snicker, E. Solano, C. Sommariva, C. Sozzi, M. Spacek, G. Spizzo, M. Spolaore, A. Stegmeir, M. Stejner, D. Stieglitz, J. Stober, U. Stroth, E. Strumberger, G. Suarez Lopez, W. Suttrop, T. Szepesi, B. Tál, T. Tala, W. Tang, G. Tardini, M. Tardocchi, D. Terranova, M. Teschke, E. Thorén, W. Tierens, D. Told, W. Treutterer, G. Trevisan, M. Tripský, P. Ulbl, G. Urbanczyk, M. Usoltseva, M. Valisa, M. Valovic, S. van Mulders, M. van Zeeland, F. Vannini, B. Vanovac, P. Varela, S. Varoutis, T. Verdier, G. Verdoolaege, N. Vianello, J. Vicente, T. Vierle, E. Viezzer, I. Voitsekhovitch, U. von Toussaint, D. Wagner, X. Wang, M. Weiland, D. Wendler, A.E. White, M. Willensdorfer, B. Wiringer, M. Wischmeier, R. Wolf, E. Wolfrum, Q. Yang, C. Yoo, Q. Yu, R. Zagórski, I. Zammuto, T. Zehetbauer, W. Zhang, W. Zholobenko, A. Zibrov, M. Zilker, C.F.B. Zimmermann, A. Zito, S. Zoletnik, the EUROfusion Tokamak Exploitation Team, and the ASDEX Upgrade Team

Subjects
tokamak, MHD stability, transport modelling, radiative exhaust, disruption physics, ELM free scenarios, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Experiments on ASDEX Upgrade (AUG) in 2021 and 2022 have addressed a number of critical issues for ITER and EU DEMO. A major objective of the AUG programme is to shed light on the underlying physics of confinement, stability, and plasma exhaust in order to allow reliable extrapolation of results obtained on present day machines to these reactor-grade devices. Concerning pedestal physics, the mitigation of edge localised modes (ELMs) using resonant magnetic perturbations (RMPs) was found to be consistent with a reduction of the linear peeling-ballooning stability threshold due to the helical deformation of the plasma. Conversely, ELM suppression by RMPs is ascribed to an increased pedestal transport that keeps the plasma away from this boundary. Candidates for this increased transport are locally enhanced turbulence and a locked magnetic island in the pedestal. The enhanced D-alpha (EDA) and quasi-continuous exhaust (QCE) regimes have been established as promising ELM-free scenarios. Here, the pressure gradient at the foot of the H-mode pedestal is reduced by a quasi-coherent mode, consistent with violation of the high-n ballooning mode stability limit there. This is suggestive that the EDA and QCE regimes have a common underlying physics origin. In the area of transport physics, full radius models for both L- and H-modes have been developed. These models predict energy confinement in AUG better than the commonly used global scaling laws, representing a large step towards the goal of predictive capability. A new momentum transport analysis framework has been developed that provides access to the intrinsic torque in the plasma core. In the field of exhaust, the X-Point Radiator (XPR), a cold and dense plasma region on closed flux surfaces close to the X-point, was described by an analytical model that provides an understanding of its formation as well as its stability, i.e., the conditions under which it transitions into a deleterious MARFE with the potential to result in a disruptive termination. With the XPR close to the divertor target, a new detached divertor concept, the compact radiative divertor, was developed. Here, the exhaust power is radiated before reaching the target, allowing close proximity of the X-point to the target. No limitations by the shallow field line angle due to the large flux expansion were observed, and sufficient compression of neutral density was demonstrated. With respect to the pumping of non-recycling impurities, the divertor enrichment was found to mainly depend on the ionisation energy of the impurity under consideration. In the area of MHD physics, analysis of the hot plasma core motion in sawtooth crashes showed good agreement with nonlinear 2-fluid simulations. This indicates that the fast reconnection observed in these events is adequately described including the pressure gradient and the electron inertia in the parallel Ohm’s law. Concerning disruption physics, a shattered pellet injection system was installed in collaboration with the ITER International Organisation. Thanks to the ability to vary the shard size distribution independently of the injection velocity, as well as its impurity admixture, it was possible to tailor the current quench rate, which is an important requirement for future large devices such as ITER. Progress was also made modelling the force reduction of VDEs induced by massive gas injection on AUG. The H-mode density limit was characterised in terms of safe operational space with a newly developed active feedback control method that allowed the stability boundary to be probed several times within a single discharge without inducing a disruptive termination. Regarding integrated operation scenarios, the role of density peaking in the confinement of the ITER baseline scenario (high plasma current) was clarified. The usual energy confinement scaling ITER98( p,y ) does not capture this effect, but the more recent H20 scaling does, highlighting again the importance of developing adequate physics based models. Advanced tokamak scenarios, aiming at large non-inductive current fraction due to non-standard profiles of the safety factor in combination with high normalised plasma pressure were studied with a focus on their access conditions. A method to guide the approach of the targeted safety factor profiles was developed, and the conditions for achieving good confinement were clarified. Based on this, two types of advanced scenarios (‘hybrid’ and ‘elevated’ q -profile) were established on AUG and characterised concerning their plasma performance.

Published
2024
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2. Inter-discharge optimization for fast, reliable access to ASDEX Upgrade advanced tokamak scenario

Author

S. Van Mulders, O. Sauter, A. Bock, A. Burckhart, C. Contré, F. Felici, R. Fischer, R. Schramm, J. Stober, H. Zohm, and the ASDEX Upgrade Team

Subjects
ASDEX Upgrade, ramp-up optimization, neoclassical tearing modes, tokamak transport, advanced tokamak scenario, pre-discharge optimization, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Rapid inter-discharge simulation and optimization using the RAPTOR code have allowed the development of a reliable and reproducible early heating strategy for an advanced tokamak (AT) scenario on ASDEX Upgrade. Solving for electron heat and current diffusion in RAPTOR with ad-hoc formulas for heat transport and electron cyclotron current drive (ECCD) efficiency is found to robustly recover the coupled dynamics of $T_{\mathrm {e}}$ and q , while maintaining model parameters fixed for all discharges. The pedestal top boundary condition in pre-shot simulations is set by a newly derived scaling law for the electron pressure at ρ = 0.8, using a data set of previous AT discharges. RAPTOR simulations have allowed to develop an understanding of the onset of 3/2 tearing modes, which were observed to have a detrimental impact on confinement when low magnetic shear conditions are present at the rational surface during the high- β phase. Delaying the NBI heating, by a specific time interval found via simulations, has led to avoiding these modes. A non-linear optimization scheme has been applied to optimize the ECCD deposition radii to reach a stationary state with $q_{\mathrm {min}} \gt 1$ at the beginning of the flat-top phase, while ensuring a non-zero magnetic shear at q = 1.5 throughout the high- β phase, and has been successfully tested in experiment. However, further experiments, aiming for $q_{\mathrm {min}} \gt 1.5$ , have highlighted limitations of the present feedforward control approach in the presence of shot-to-shot variations that are not included in the applied model. Application of real-time model-based control is proposed to overcome model-reality mismatches in future work.

Published
2024
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3. Overview of the EUROfusion Tokamak Exploitation programme in support of ITER and DEMO

Author

E. Joffrin, M. Wischmeier, M. Baruzzo, A. Hakola, A. Kappatou, D. Keeling, B. Labit, E. Tsitrone, N. Vianello, the ASDEX Upgrade Team, JET Contributors, the MAST-U Team, the TCV Team, the WEST Team, the EUROfusion Tokamak Exploitation Team:, D. Abate, J. Adamek, M. Agostini, C. Albert, F.C.P. Albert Devasagayam, S. Aleiferis, E. Alessi, J. Alhage, S. Allan, J. Allcock, M. Alonzo, G. Anastasiou, E. Andersson Sunden, C. Angioni, Y. Anquetin, L. Appel, G.M. Apruzzese, M. Ariola, C. Arnas, J.F. Artaud, W. Arter, O. Asztalos, L. Aucone, M.H. Aumeunier, F. Auriemma, J. Ayllon, E. Aymerich, A. Baciero, F. Bagnato, L. Bähner, F. Bairaktaris, P. Balázs, L. Balbinot, I. Balboa, M. Balden, A. Balestri, M. Baquero Ruiz, T. Barberis, C. Barcellona, O. Bardsley, S. Benkadda, T. Bensadon, E. Bernard, M. Bernert, H. Betar, R. Bianchetti Morales, J. Bielecki, R. Bilato, P. Bilkova, W. Bin, G. Birkenmeier, R. Bisson, P. Blanchard, A. Bleasdale, V. Bobkov, A. Boboc, A. Bock, K. Bogar, P. Bohm, T. Bolzonella, F. Bombarda, N. Bonanomi, L. Boncagni, D. Bonfiglio, R. Bonifetto, M. Bonotto, D. Borodin, I. Borodkina, T.O.S.J. Bosman, C. Bourdelle, C. Bowman, S. Brezinsek, D. Brida, F. Brochard, R. Brunet, D. Brunetti, V. Bruno, R. Buchholz, J. Buermans, H. Bufferand, P. Buratti, A. Burckhart, J. Cai, R. Calado, J. Caloud, S. Cancelli, F. Cani, B. Cannas, M. Cappelli, S. Carcangiu, A. Cardinali, S. Carli, D. Carnevale, M. Carole, M. Carpita, D. Carralero, F. Caruggi, I.S. Carvalho, I. Casiraghi, A. Casolari, F.J. Casson, C. Castaldo, A. Cathey, F. Causa, J. Cavalier, M. Cavedon, J. Cazabonne, M. Cecconello, L. Ceelen, A. Celora, J. Cerovsky, C.D. Challis, R. Chandra, A. Chankin, B. Chapman, H. Chen, M. Chernyshova, A.G. Chiariello, P. Chmielewski, A. Chomiczewska, C. Cianfarani, G. Ciraolo, J. Citrin, F. Clairet, S. Coda, R. Coelho, J.W. Coenen, I.H. Coffey, C. Colandrea, L. Colas, S. Conroy, C. Contre, N.J. Conway, L. Cordaro, Y. Corre, D. Costa, S. Costea, D. Coster, X. Courtois, C. Cowley, T. Craciunescu, G. Croci, A.M. Croitoru, K. Crombe, D.J. Cruz Zabala, G. Cseh, T. Czarski, A. Da Ros, A. Dal Molin, M. Dalla Rosa, Y. Damizia, O. D’Arcangelo, P. David, M. De Angeli, E. De la Cal, E. De La Luna, G. De Tommasi, J. Decker, R. Dejarnac, D. Del Sarto, G. Derks, C. Desgranges, P. Devynck, S. Di Genova, L.E. di Grazia, A. Di Siena, M. Dicorato, M. Diez, M. Dimitrova, T. Dittmar, L. Dittrich, J.J. Domínguez Palacios Durán, P. Donnel, D. Douai, S. Dowson, S. Doyle, M. Dreval, P. Drews, L. Dubus, R. Dumont, D. Dunai, M. Dunne, A. Durif, F. Durodie, G. Durr Legoupil Nicoud, B. Duval, R. Dux, T. Eich, A. Ekedahl, S. Elmore, G. Ericsson, J. Eriksson, B. Eriksson, F. Eriksson, S. Ertmer, A. Escarguel, B. Esposito, T. Estrada, E. Fable, M. Faitsch, N. Fakhrayi Mofrad, A. Fanni, T. Farley, M. Farník, N. Fedorczak, F. Felici, X. Feng, J. Ferreira, D. Ferreira, N. Ferron, O. Fevrier, O. Ficker, A.R. Field, A. Figueiredo, N. Fil, D. Fiorucci, M. Firdaouss, R. Fischer, M. Fitzgerald, M. Flebbe, M. Fontana, J. Fontdecaba Climent, A. Frank, E. Fransson, L. Frassinetti, D. Frigione, S. Futatani, R. Futtersack, S. Gabriellini, D. Gadariya, D. Galassi, K. Galazka, J. Galdon, S. Galeani, D. Gallart, A. Gallo, C. Galperti, M. Gambrioli, S. Garavaglia, J. Garcia, M. Garcia Munoz, J. Gardarein, L. Garzotti, J. Gaspar, R. Gatto, P. Gaudio, M. Gelfusa, J. Gerardin, S.N. Gerasimov, R. Gerru Miguelanez, G. Gervasini, Z. Ghani, F.M. Ghezzi, G. Ghillardi, L. Giannone, S. Gibson, L. Gil, A. Gillgren, E. Giovannozzi, C. Giroud, G. Giruzzi, T. Gleiter, M. Gobbin, V. Goloborodko, A. González Ganzábal, T. Goodman, V. Gopakumar, G. Gorini, T. Görler, S. Gorno, G. Granucci, D. Greenhouse, G. Grenfell, M. Griener, W. Gromelski, M. Groth, O. Grover, M. Gruca, A. Gude, C. Guillemaut, R. Guirlet, J. Gunn, T. Gyergyek, L. Hagg, J. Hall, C.J. Ham, M. Hamed, T. Happel, G. Harrer, J. Harrison, D. Harting, N.C. Hawkes, P. Heinrich, S. Henderson, P. Hennequin, R. Henriques, S. Heuraux, J. Hidalgo Salaverri, J. Hillairet, J.C. Hillesheim, A. Hjalmarsson, A. Ho, J. Hobirk, E. Hodille, M. Hölzl, M. Hoppe, J. Horacek, N. Horsten, L. Horvath, M. Houry, K. Hromasova, J. Huang, Z. Huang, A. Huber, E. Huett, P. Huynh, A. Iantchenko, M. Imrisek, P. Innocente, C. Ionita Schrittwieser, H. Isliker, P. Ivanova, I. Ivanova Stanik, M. Jablczynska, S. Jachmich, A.S. Jacobsen, P. Jacquet, A. Jansen van Vuuren, A. Jardin, H. Järleblad, A. Järvinen, F. Jaulmes, T. Jensen, I. Jepu, S. Jessica, T. Johnson, A. Juven, J. Kalis, J. Karhunen, R. Karimov, A.N. Karpushov, S. Kasilov, Y. Kazakov, P.V. Kazantzidis, W. Kernbichler, HT. Kim, D.B. King, V.G. Kiptily, A. Kirjasuo, K.K. Kirov, A. Kirschner, A. Kit, T. Kiviniemi, F. Kjær, E. Klinkby, A. Knieps, U. Knoche, M. Kochan, F. Köchl, G. Kocsis, J.T.W. Koenders, L. Kogan, Y. Kolesnichenko, Y. Kominis, M. Komm, M. Kong, B. Kool, S.B. Korsholm, D. Kos, M. Koubiti, J. Kovacic, Y. Kovtun, E. Kowalska Strzeciwilk, K. Koziol, M. Kozulia, A. Krämer Flecken, A. Kreter, K. Krieger, U. Kruezi, O. Krutkin, O. Kudlacek, U. Kumar, H. Kumpulainen, M.H. Kushoro, R. Kwiatkowski, M. La Matina, M. Lacquaniti, L. Laguardia, P. Lainer, P. Lang, M. Larsen, E. Laszynska, K.D. Lawson, A. Lazaros, E. Lazzaro, M.Y.K. Lee, S. Leerink, M. Lehnen, M. Lennholm, E. Lerche, Y. Liang, A. Lier, J. Likonen, O. Linder, B. Lipschultz, A. Listopad, X. Litaudon, E. Litherland Smith, D. Liuzza, T. Loarer, P.J. Lomas, J. Lombardo, N. Lonigro, R. Lorenzini, C. Lowry, T. Luda di Cortemiglia, A. Ludvig Osipov, T. Lunt, V. Lutsenko, E. Macusova, R. Mäenpää, P. Maget, C.F. Maggi, J. Mailloux, S. Makarov, K. Malinowski, P. Manas, A. Mancini, D. Mancini, P. Mantica, M. Mantsinen, J. Manyer, M. Maraschek, G. Marceca, G. Marcer, C. Marchetto, S. Marchioni, A. Mariani, M. Marin, M. Markl, T. Markovic, D. Marocco, S. Marsden, L. Martellucci, P. Martin, C. Martin, F. Martinelli, L. Martinelli, J.R. Martin Solis, R. Martone, M. Maslov, R. Masocco, M. Mattei, G.F. Matthews, D. Matveev, E. Matveeva, M.L. Mayoral, D. Mazon, S. Mazzi, C. Mazzotta, G. McArdle, R. McDermott, K. McKay, A.G. Meigs, C. Meineri, A. Mele, V. Menkovski, S. Menmuir, A. Merle, H. Meyer, K. Mikszuta Michalik, D. Milanesio, F. Militello, A. Milocco, I.G. Miron, J. Mitchell, R. Mitteau, V. Mitterauer, J. Mlynar, V. Moiseenko, P. Molna, F. Mombelli, C. Monti, A. Montisci, J. Morales, P. Moreau, J.M. Moret, A. Moro, D. Moulton, P. Mulholland, M. Muraglia, A. Murari, A. Muraro, P. Muscente, D. Mykytchuk, F. Nabais, Y. Nakeva, F. Napoli, E. Nardon, M.F. Nave, R.D. Nem, A. Nielsen, S.K. Nielsen, M. Nocente, R. Nouailletas, S. Nowak, H. Nyström, R. Ochoukov, N. Offeddu, S. Olasz, C. Olde, F. Oliva, D. Oliveira, H.J.C. Oliver, P. Ollus, J. Ongena, F.P. Orsitto, N. Osborne, R. Otin, P. Oyola Dominguez, D.I. Palade, S. Palomba, O. Pan, N. Panadero, E. Panontin, A. Papadopoulos, P. Papagiannis, G. Papp, V.V. Parail, C. Pardanaud, J. Parisi, A. Parrott, K. Paschalidis, M. Passoni, F. Pastore, A. Patel, B. Patel, A. Pau, G. Pautasso, R. Pavlichenko, E. Pawelec, B. Pegourie, G. Pelka, E. Peluso, A. Perek, E. Perelli Cippo, C. Perez Von Thun, P. Petersson, G. Petravich, Y. Peysson, V. Piergotti, L. Pigatto, C. Piron, L. Piron, A. Pironti, F. Pisano, U. Plank, B. Ploeckl, V. Plyusnin, A. Podolnik, Y. Poels, G. Pokol, J. Poley, G. Por, M. Poradzinski, F. Porcelli, L. Porte, C. Possieri, A. Poulsen, I. Predebon, G. Pucella, M. Pueschel, P. Puglia, O. Putignano, T. Pütterich, V. Quadri, A. Quercia, M. Rabinski, L. Radovanovic, R. Ragona, H. Raj, M. Rasinski, J. Rasmussen, G. Ratta, S. Ratynskaia, R. Rayaprolu, M. Rebai, A. Redl, D. Rees, D. Refy, M. Reich, H. Reimerdes, B.C.G. Reman, O. Renders, C. Reux, D. Ricci, M. Richou, S. Rienacker, D. Rigamonti, F. Rigollet, F.G. Rimini, D. Ripamonti, N. Rispoli, N. Rivals, J.F. Rivero Rodriguez, C. Roach, G. Rocchi, S. Rode, P. Rodrigues, J. Romazanov, C.F. Romero Madrid, J. Rosato, R. Rossi, G. Rubino, J. Rueda Rueda, J. Ruiz Ruiz, P. Ryan, D. Ryan, S. Saarelma, R. Sabot, M. Salewski, A. Salmi, L. Sanchis, A. Sand, J. Santos, K. Särkimäki, M. Sassano, O. Sauter, G. Schettini, S. Schmuck, P. Schneider, N. Schoonheere, R. Schramm, R. Schrittwieser, C. Schuster, N. Schwarz, F. Sciortino, M. Scotto D’Abusco, S. Scully, A. Selce, L. Senni, M. Senstius, G. Sergienko, S.E. Sharapov, R. Sharma, A. Shaw, U. Sheikh, G. Sias, B. Sieglin, S.A. Silburn, C. Silva, A. Silva, D. Silvagni, B. Simmendefeldt Schmidt, L. Simons, J. Simpson, L. Singh, S. Sipilä, Y. Siusko, S. Smith, A. Snicker, E.R. Solano, V. Solokha, M. Sos, C. Sozzi, F. Spineanu, G. Spizzo, M. Spolaore, L. Spolladore, C. Srinivasan, A. Stagni, Z. Stancar, G. Stankunas, J. Stober, P. Strand, C.I. Stuart, F. Subba, G.Y. Sun, H.J. Sun, W. Suttrop, J. Svoboda, T. Szepesi, G. Szepesi, B. Tal, T. Tala, P. Tamain, G. Tardini, M. Tardocchi, D. Taylor, G. Telesca, A. Tenaglia, A. Terra, D. Terranova, D. Testa, C. Theiler, E. Tholerus, B. Thomas, E. Thoren, A. Thornton, A. Thrysoe, Q. TICHIT, W. Tierens, A. Titarenko, P. Tolias, E. Tomasina, M. Tomes, E. Tonello, A. Tookey, M. Toscano Jiménez, C. Tsironis, C. Tsui, A. Tykhyy, M. Ugoletti, M. Usoltseva, D.F. Valcarcel, A. Valentini, M. Valisa, M. Vallar, M. Valovic, SI. Valvis, M. van Berkel, D. Van Eester, S. Van Mulders, M. van Rossem, R. Vann, B. Vanovac, J. Varela Rodriguez, J. Varje, S. Vartanian, M. Vecsei, L. Velarde Gallardo, M. Veranda, T. Verdier, G. Verdoolaege, K. Verhaegh, L. Vermare, G. Verona Rinati, J. Vicente, E. Viezzer, L. Vignitchouk, F. Villone, B. Vincent, P. Vincenzi, M.O. Vlad, G. Vogel, I. Voitsekhovitch, I. Voldiner, P. Vondracek, N.M.T. VU, T. Vuoriheimo, C. Wade, E. Wang, T. Wauters, M. Weiland, H. Weisen, N. Wendler, D. Weston, A. Widdowson, S. Wiesen, M. Wiesenberger, T. Wijkamp, M. Willensdorfer, T. Wilson, A. Wojenski, C. Wuethrich, I. Wyss, L. Xiang, S. Xu, D. Yadykin, Y. Yakovenko, H. Yang, V. Yanovskiy, R. Yi, B. Zaar, G. Zadvitskiy, L. Zakharov, P. Zanca, D. Zarzoso, Y. Zayachuk, J. Zebrowski, M. Zerbini, P. Zestanakis, C. F. B. Zimmermann, M. Zlobinski, A. Zohar, V.K. Zotta, X. Zou, M. Zuin, M. Zurita, and I. Zychor

Subjects
JET, ASDEX Upgrade, MAST-U, TCV, WEST, Tokamak Exploitation Task Force, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Within the 9th European Framework programme, since 2021 EUROfusion is operating five tokamaks under the auspices of a single Task Force called ‘Tokamak Exploitation’. The goal is to benefit from the complementary capabilities of each machine in a coordinated way and help in developing a scientific output scalable to future largre machines. The programme of this Task Force ensures that ASDEX Upgrade, MAST-U, TCV, WEST and JET (since 2022) work together to achieve the objectives of Missions 1 and 2 of the EUROfusion Roadmap: i) demonstrate plasma scenarios that increase the success margin of ITER and satisfy the requirements of DEMO and, ii) demonstrate an integrated approach that can handle the large power leaving ITER and DEMO plasmas. The Tokamak Exploitation task force has therefore organized experiments on these two missions with the goal to strengthen the physics and operational basis for the ITER baseline scenario and for exploiting the recent plasma exhaust enhancements in all four devices (PEX: Plasma EXhaust) for exploring the solution for handling heat and particle exhaust in ITER and develop the conceptual solutions for DEMO. The ITER Baseline scenario has been developed in a similar way in ASDEX Upgrade, TCV and JET. Key risks for ITER such as disruptions and run-aways have been also investigated in TCV, ASDEX Upgrade and JET. Experiments have explored successfully different divertor configurations (standard, super-X, snowflakes) in MAST-U and TCV and studied tungsten melting in WEST and ASDEX Upgrade. The input from the smaller devices to JET has also been proven successful to set-up novel control schemes on disruption avoidance and detachment.

Published
2024
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4. Experimental evidence of magnetic flux pumping in ASDEX upgrade

Author

A. Burckhart, A. Bock, R. Fischer, T. Pütterich, J. Stober, S. Günter, A. Gude, J. Hobirk, M. Hölzl, V. Igochine, I. Krebs, M. Maraschek, M. Reisner, R. Schramm, H. Zohm, and the ASDEX Upgrade Team

Subjects
flux pumping, dynamo, sawteeth, ASDEX upgrade, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

In high- β scenarios with on-axis co-current electron cyclotron current drive, which normally lowers q _0 below unity, the absence of sawteeth suggests the involvement of an additional current redistribution mechanism beyond neoclassical current diffusion. This is supported by imaging motional Stark effect diagnostic measurements, which indicate that q _0 remains consistently around 1. This phenomenon is observed in the presence of a 1/1 mode, indicating its potential role in the current redistribution. It is shown that the mode’s ability to modify the central current and suppress sawteeth increases with plasma pressure. These findings align with a recent theoretical model, which predicts a pressure threshold for sawtooth avoidance by a 1/1 quasi-interchange mode and where this threshold increases with the strength of inward current diffusion. Moreover, the advantages of the flux pumping scenario for future machines are highlighted.

Published
2023
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5. Long plasma duration operation analyses with an international multi-machine (tokamaks and stellarators) database

Author

X. Litaudon, H.-S. Bosch, T. Morisaki, M. Barbarino, A. Bock, E. Belonohy, S. Brezinsek, J. Bucalossi, S. Coda, R. Daniel, A. Ekedahl, K. Hanada, C. Holcomb, J. Huang, S. Ide, M. Jakubowski, B. V. Kuteev, E. Lerche, T. Luce, P. Maget, Y. Song, J. Stober, D. VAN Houtte, Y. Xi, L. Xue, S. Yoon, B. Zhang, and JET contributors

Subjects
nuclear fusion, long plasma duration operation, international multi-machine (tokamaks and stellarators) database, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Combined high-fusion performance and long-pulse operation is one of the key integration challenges for fusion energy development in magnetic devices. Addressing these challenges requires an integrated vision of physics and engineering aspects with the purpose of simultaneously increasing time duration and fusion performance. Significant progress has been made in tokamaks and stellarators, including very recent achievement in duration and/or performance. This progress is reviewed by analyzing the experimental data (109 plasma pulses with a total of 3200 data points, i.e. on average 29 data per pulse) provided by ten tokamaks (in alphabetical order: Axially Symmetric Divertor Experiment Upgrade, DIII-D, Experimental Advanced Superconducting Tokamak, Joint European Torus, JT-60 Upgrade, Korea Superconducting Tokamak Advanced Research, tokamak à configuration variable, Tokamak Fusion Test Reactor, Tore Supra, W Environment in Steady-State Tokamak) and two stellarators (Large Helical Device and Wendelstein 7-X) expanding the pioneering work of Kikuchi (Kikuchi M. and Azumi M. 2015 Frontiers in Fusion Research II: Introduction to Modern Tokamak Physics (Springer)). Data have been gathered up to January 2022 and coordination has been provided by the recently created International Energy Agency-International Atomic Energy Agency international C oordination on I nternational C hallenges on L ong duration OP eration group. By exploiting the multi-machine international database, recent progress in terms of injected energies (e.g. 1730 MJ in L-mode, 425 MJ in H-mode), durations (1056 s in L-mode, 101 s in H-mode), injected powers, and sustained performance will be reviewed. Progress has been made to sustain long-pulse operation in tokamaks and stellarators with superconducting coils, actively cooled components, and/or with metallic walls. The graph of the fusion triple products as a function of duration shows a dramatic reduction of, at least two orders of magnitude when increasing the plasma duration from less than 1 s to 100 s. Indeed, long-pulse operation is usually reached in dominant electron-heating modes at reduced density (current drive optimization) but with low ion temperatures ranging from 1 to 3 keV for discharges above 100 s. Difficulties in extending the duration may arise from coupling high heating powers over long durations and the evolving plasma-wall interaction towards an unstable operational domain. Possible causes limiting the duration and critical issues to be addressed prior to ITER operation and DEMO design are reported and analyzed.

Published
2023
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6. Modelling of energetic particle drive and damping effects on TAEs in AUG experiment with ECCD

Author

R. Calado, F. Nabais, S.E. Sharapov, P. Schneider, Ye. Kazakov, M. Garcia-Muñoz, A. Snicker, J. Ferreira, R. Coelho, M. Dreval, J. Fuertes, J. Galdon-Quiroga, J. Gonzalez-Martin, A. Karpushov, J. Stober, G. Tardini, M.A. Van Zeeland, and the ASDEX Upgrade Team

Subjects
tokamaks, Alfvén eigenmodes, energetic ions, ECCD, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

The impact of electron cyclotron current drive (ECCD)-driven current on toroidicity-induced Alfvén eigenmodes (TAEs) in experiments on the AUG tokamak is investigated numerically. The dynamical evolution of the plasma profiles and equilibria are modelled with European transport solver, while ion cyclotron resonance heating-accelerated H-minority ions exciting TAEs are assessed with the PION code. TAEs, their drive and damping are computed with the codes CASTOR and CASTOR-K. In the set of discharges analysed, two groups of TAEs are observed, differing in frequency and radial location. Experimental observations show that when counter-ECCD is applied the higher frequency group of approximately 150 kHz is suppressed, while the lower frequency modes of 125 kHz are amplified. When co-ECCD is applied, depending on the location of the ECCD current deposition layer, both groups of TAE can be suppressed. Numerical calculations of energetic particle drive and thermal plasma damping show that neither one effect could explain the variety of the experimental observations. The fine balance between the drive, sensitive to the TAE position, and the radiative and continuum damping effects could only explain the experiment if the effects are considered all together.

Published
2023
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7. Characterisation of electron cyclotron wall conditioning plasma in ASDEX Upgrade

Author

T. Wauters, J. Buermans, J. Cavalier, E. Huett, R. Ragona, J. Svoboda, V. Bobkov, M. Griener, A.S. Jacobsen, A. Kallenbach, J. Likonen, T. Loarer, T. Lunt, S.K. Nielsen, R.A. Pitts, D. Ricci, V. Rohde, J. Stober, P. Schneider, M. Usoltseva, the ASDEX Upgrade Team, and the EUROfusion MST1 Team

Subjects
ECWC, ECRH, ITER, wall conditioning, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Electron cyclotron wall condition (ECWC) discharges are characterised in ASDEX Upgrade with full tungsten plasma facing components and X2 polarised waves launched from the equatorial ports, relevant to ECWC conditions in ITER Pre-Fusion Power Operation phase 1. The characterisation of the deuterium plasmas is based on experimental inputs such as electron density measurements, in-vessel pressure measurements, poloidal field maps obtained from the measured coil currents, as well as advanced tomographic methods on camera images filtered at the hydrogen Balmer lines. TOMATOR-1D simulations and collective Thomson scattering radiometer spectra complement the findings. The cold, high density and partially ionized toroidal plasmas show significant levels of stray radiation. The measured radiation includes waves at half of the gyrotron frequency suggesting the occurrence of parametric decay instabilities at 2nd harmonic upper hybrid resonance that locates at the low field side of the resonance. A displacement of the plasma emission along the resonance layer is observed at higher discharge power in discharges with a vertical poloidal magnetic field only. By optimizing the poloidal field pattern, along with the location of the electron cyclotron heating (ECH) resonance, the strongest surface interaction regions for the charged particles can be controlled. Directing plasma flux to inner wall surfaces, and same for the inner divertor apron, is found less effective in ASDEX Upgrade due to magnetic mirror effects and outward convective flows. Modeling however predicts the presence of an intense and uniform flux of low energy atoms produced at the ECH absorption layer that may be effective for conditioning the high field side surfaces after use of the disruption mitigation system.

Published
2023
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8. A practical protocol to emulate a reactor scenario on present machines, with application to the ASDEX Upgrade tokamak via predictive modeling

Author

E. Fable, P. David, O. Kudlacek, C. Hopf, B. Sieglin, J. Stober, W. Treutterer, M. Weiland, C. Wu, H. Zohm, and the ASDEX Upgrade Team

Subjects
tokamak, control, scenario, burning plasma, nonlinearity, alpha power, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

In this work, a novel practical strategy to emulate a reactor scenario on present tokamak experiments is presented. A recipe how to scale several relevant parameters from a hypothetical reactor scenario down to present devices is discussed. Equivalence between the energy flux channels is detailed, and the practical actuation scheme is presented. The application of the proposed protocol on the ASDEX Upgrade tokamak is shown foremost using the virtual flight simulator Fenix, with practical experiments planned for future campaigns.

Published
2023
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9. Progress from ASDEX Upgrade experiments in preparing the physics basis of ITER operation and DEMO scenario development

Author

U. Stroth, D. Aguiam, E. Alessi, C. Angioni, N. Arden, R. Arredondo Parra, V. Artigues, O. Asunta, M. Balden, V. Bandaru, A. Banon-Navarro, K. Behler, A. Bergmann, M. Bergmann, J. Bernardo, M. Bernert, A. Biancalani, R. Bielajew, R. Bilato, G. Birkenmeier, T. Blanken, V. Bobkov, A. Bock, T. Body, T. Bolzonella, N. Bonanomi, A. Bortolon, B. Böswirth, C. Bottereau, A. Bottino, H. van den Brand, M. Brenzke, S. Brezinsek, D. Brida, F. Brochard, C. Bruhn, J. Buchanan, A. Buhler, A. Burckhart, Y. Camenen, B. Cannas, P. Cano Megias, D. Carlton, M. Carr, P. Carvalho, C. Castaldo, M. Cavedon, C. Cazzaniga, C. Challis, A. Chankin, C. Cianfarani, F. Clairet, S. Coda, R. Coelho, J.W. Coenen, L. Colas, G. Conway, S. Costea, D. Coster, T. Cote, A.J. Creely, G. Croci, D.J. Cruz Zabala, G. Cseh, A. Czarnecka, I. Cziegler, O. D’Arcangelo, A. Dal Molin, P. David, C. Day, M. de Baar, P. de Marné, R. Delogu, S. Denk, P. Denner, A. Di Siena, J.J. Dominguez Palacios Durán, D. Dunai, A. Drenik, M. Dreval, R. Drube, M. Dunne, B.P. Duval, R. Dux, T. Eich, S. Elgeti, A. Encheva, K. Engelhardt, B. Erdös, I. Erofeev, B. Esposito, E. Fable, M. Faitsch, U. Fantz, M. Farnik, H. Faugel, F. Felici, O. Ficker, S. Fietz, A. Figueredo, R. Fischer, O. Ford, L. Frassinetti, M. Fröschle, G. Fuchert, J.C. Fuchs, H. Fünfgelder, S. Futatani, K. Galazka, J. Galdon-Quiroga, D. Gallart Escolà, A. Gallo, Y. Gao, S. Garavaglia, M. Garcia Muñoz, B. Geiger, L. Giannone, S. Gibson, L. Gil, E. Giovannozzi, S. Glöggler, M. Gobbin, J. Gonzalez Martin, T. Goodman, G. Gorini, T. Görler, D. Gradic, G. Granucci, A. Gräter, H. Greuner, M. Griener, M. Groth, A. Gude, L. Guimarais, S. Günter, G. Haas, A.H. Hakola, C. Ham, T. Happel, N. den Harder, G. Harrer, J. Harrison, V. Hauer, T. Hayward-Schneider, B. Heinemann, T. Hellsten, S. Henderson, P. Hennequin, A. Herrmann, E. Heyn, F. Hitzler, J. Hobirk, K. Höfler, J.H. Holm, M. Hölzl, C. Hopf, L. Horvath, T. Höschen, A. Houben, A. Hubbard, A. Huber, K. Hunger, V. Igochine, M. Iliasova, T. Ilkei, K. Insulander Björk, C. Ionita-Schrittwieser, I. Ivanova-Stanik, W. Jacob, N. Jaksic, F. Janky, A. Jansen van Vuuren, A. Jardin, F. Jaulmes, F. Jenko, T. Jensen, E. Joffrin, A. Kallenbach, S. Kálvin, M. Kantor, A. Kappatou, O. Kardaun, J. Karhunen, C.-P. Käsemann, S. Kasilov, A. Kendl, W. Kernbichler, E. Khilkevitch, A. Kirk, S. Kjer Hansen, V. Klevarova, G. Kocsis, M. Koleva, M. Komm, M. Kong, A. Krämer-Flecken, K. Krieger, A. Krivska, O. Kudlacek, T. Kurki-Suonio, B. Kurzan, B. Labit, K. Lackner, F. Laggner, A. Lahtinen, P.T. Lang, P. Lauber, N. Leuthold, L. Li, J. Likonen, O. Linder, B. Lipschultz, Y. Liu, A. Lohs, Z. Lu, T. Luda di Cortemiglia, N.C. Luhmann, T. Lunt, A. Lyssoivan, T. Maceina, J. Madsen, A. Magnanimo, H. Maier, J. Mailloux, R. Maingi, O. Maj, E. Maljaars, P. Manas, A. Mancini, A. Manhard, P. Mantica, M. Mantsinen, P. Manz, M. Maraschek, C. Marchetto, L. Marrelli, P. Martin, A. Martitsch, F. Matos, M. Mayer, M.-L. Mayoral, D. Mazon, P.J. McCarthy, R. McDermott, R. Merkel, A. Merle, D. Meshcheriakov, H. Meyer, D. Milanesio, P. Molina Cabrera, F. Monaco, M. Muraca, F. Nabais, V. Naulin, R. Nazikian, R.D. Nem, A. Nemes-Czopf, G. Neu, R. Neu, A.H. Nielsen, S.K. Nielsen, T. Nishizawa, M. Nocente, J.-M. Noterdaeme, I. Novikau, S. Nowak, M. Oberkofler, R. Ochoukov, J. Olsen, F. Orain, F. Palermo, O. Pan, G. Papp, I. Paradela Perez, A. Pau, G. Pautasso, C. Paz-Soldan, P. Petersson, P. Piovesan, C. Piron, U. Plank, B. Plaum, B. Plöck, V. Plyusnin, G. Pokol, E. Poli, L. Porte, T. Pütterich, M. Ramisch, J. Rasmussen, G. Ratta, S. Ratynskaia, G. Raupp, D. Réfy, M. Reich, F. Reimold, D. Reiser, M. Reisner, D. Reiter, T. Ribeiro, R. Riedl, J. Riesch, D. Rittich, J.F. Rivero Rodriguez, G. Rocchi, P. Rodriguez-Fernandez, M. Rodriguez-Ramos, V. Rohde, G. Ronchi, A. Ross, M. Rott, M. Rubel, D.A. Ryan, F. Ryter, S. Saarelma, M. Salewski, A. Salmi, O. Samoylov, L. Sanchis Sanchez, J. Santos, O. Sauter, G. Schall, K. Schlüter, K. Schmid, O. Schmitz, P.A. Schneider, R. Schrittwieser, M. Schubert, C. Schuster, T. Schwarz-Selinger, J. Schweinzer, E. Seliunin, A. Shabbir, A. Shalpegin, S. Sharapov, U. Sheikh, A. Shevelev, G. Sias, M. Siccinio, B. Sieglin, A. Sigalov, A. Silva, C. Silva, D. Silvagni, J. Simpson, S. Sipilä, E. Smigelskis, A. Snicker, E. Solano, C. Sommariva, C. Sozzi, G. Spizzo, M. Spolaore, A. Stegmeir, M. Stejner, J. Stober, E. Strumberge, G. Suarez Lopez, H.-J. Sun, W. Suttrop, E. Sytova, T. Szepesi, B. Tál, T. Tala, G. Tardini, M. Tardocchi, D. Terranova, M. Teschke, E. Thorén, W. Tierens, D. Told, W. Treutterer, G. Trevisan, E. Trier, M. Tripský, M. Usoltceva, M. Valisa, M. Valovic, M. van Zeeland, F. Vannini, B. Vanovac, P. Varela, S. Varoutis, N. Vianello, J. Vicente, G. Verdoolaege, T. Vierle, E. Viezzer, I. Voitsekhovitch, U. von Toussaint, D. Wagner, X. Wang, M. Weiland, A.E. White, M. Willensdorfer, B. Wiringer, M. Wischmeier, R. Wolf, E. Wolfrum, Q. Yang, Q. Yu, R. Zagórski, I. Zammuto, T. Zehetbauer, W. Zhang, W. Zholobenko, M. Zilker, A. Zito, H. Zohm, S. Zoletnik, the EUROfusion MST1 Team, Max-Planck-Institut für Plasmaphysik [Garching] (IPP), Institut de Recherche sur la Fusion par confinement Magnétique (IRFM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Aix Marseille Université (AMU), Laboratoire de Physique des Plasmas (LPP), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École polytechnique (X)-Sorbonne Université (SU)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), EUROfusion MST1 Team, Barcelona Supercomputing Center, Department of Applied Physics, Aalto-yliopisto, Aalto University, Stroth, U, Aguiam, D, Alessi, E, Angioni, C, Arden, N, Parra, R, Artigues, V, Asunta, O, Balden, M, Bandaru, V, Banon-Navarro, A, Behler, K, Bergmann, A, Bergmann, M, Bernardo, J, Bernert, M, Biancalani, A, Bielajew, R, Bilato, R, Birkenmeier, G, Blanken, T, Bobkov, V, Bock, A, Body, T, Bolzonella, T, Bonanomi, N, Bortolon, A, Boswirth, B, Bottereau, C, Bottino, A, Van Den Brand, H, Brenzke, M, Brezinsek, S, Brida, D, Brochard, F, Bruhn, C, Buchanan, J, Buhler, A, Burckhart, A, Camenen, Y, Cannas, B, Megias, P, Carlton, D, Carr, M, Carvalho, P, Castaldo, C, Cavedon, M, Cazzaniga, C, Challis, C, Chankin, A, Cianfarani, C, Clairet, F, Coda, S, Coelho, R, Coenen, J, Colas, L, Conway, G, Costea, S, Coster, D, Cote, T, Creely, A, Croci, G, Zabala, D, Cseh, G, Czarnecka, A, Cziegler, I, D'Arcangelo, O, Molin, A, David, P, Day, C, De Baar, M, De Marne, P, Delogu, R, Denk, S, Denner, P, Di Siena, A, Palacios Duran, J, Dunai, D, Drenik, A, Dreval, M, Drube, R, Dunne, M, Duval, B, Dux, R, Eich, T, Elgeti, S, Encheva, A, Engelhardt, K, Erdos, B, Erofeev, I, Esposito, B, Fable, E, Faitsch, M, Fantz, U, Farnik, M, Faugel, H, Felici, F, Ficker, O, Fietz, S, Figueredo, A, Fischer, R, Ford, O, Frassinetti, L, Froschle, M, Fuchert, G, Fuchs, J, Funfgelder, H, Futatani, S, Galazka, K, Galdon-Quiroga, J, Escola, D, Gallo, A, Gao, Y, Garavaglia, S, Munoz, M, Geiger, B, Giannone, L, Gibson, S, Gil, L, Giovannozzi, E, Gloggler, S, Gobbin, M, Martin, J, Goodman, T, Gorini, G, Gorler, T, Gradic, D, Granucci, G, Grater, A, Greuner, H, Griener, M, Groth, M, Gude, A, Guimarais, L, Gunter, S, Haas, G, Hakola, A, Ham, C, Happel, T, Den Harder, N, Harrer, G, Harrison, J, Hauer, V, Hayward-Schneider, T, Heinemann, B, Hellsten, T, Henderson, S, Hennequin, P, Herrmann, A, Heyn, E, Hitzler, F, Hobirk, J, Hofler, K, Holm, J, Holzl, M, Hopf, C, Horvath, L, Hoschen, T, Houben, A, Hubbard, A, Huber, A, Hunger, K, Igochine, V, Iliasova, M, Ilkei, T, Bjork, K, Ionita-Schrittwieser, C, Ivanova-Stanik, I, Jacob, W, Jaksic, N, Janky, F, Jansen Van Vuuren, A, Jardin, A, Jaulmes, F, Jenko, F, Jensen, T, Joffrin, E, Kallenbach, A, Kalvin, S, Kantor, M, Kappatou, A, Kardaun, O, Karhunen, J, Kasemann, C, Kasilov, S, Kendl, A, Kernbichler, W, Khilkevitch, E, Kirk, A, Hansen, S, Klevarova, V, Kocsis, G, Koleva, M, Komm, M, Kong, M, Kramer-Flecken, A, Krieger, K, Krivska, A, Kudlacek, O, Kurki-Suonio, T, Kurzan, B, Labit, B, Lackner, K, Laggner, F, Lahtinen, A, Lang, P, Lauber, P, Leuthold, N, Li, L, Likonen, J, Linder, O, Lipschultz, B, Liu, Y, Lohs, A, Lu, Z, Luda Di Cortemiglia, T, Luhmann, N, Lunt, T, Lyssoivan, A, Maceina, T, Madsen, J, Magnanimo, A, Maier, H, Mailloux, J, Maingi, R, Maj, O, Maljaars, E, Manas, P, Mancini, A, Manhard, A, Mantica, P, Mantsinen, M, Manz, P, Maraschek, M, Marchetto, C, Marrelli, L, Martin, P, Martitsch, A, Matos, F, Mayer, M, Mayoral, M, Mazon, D, Mccarthy, P, Mcdermott, R, Merkel, R, Merle, A, Meshcheriakov, D, Meyer, H, Milanesio, D, Cabrera, P, Monaco, F, Muraca, M, Nabais, F, Naulin, V, Nazikian, R, Nem, R, Nemes-Czopf, A, Neu, G, Neu, R, Nielsen, A, Nielsen, S, Nishizawa, T, Nocente, M, Noterdaeme, J, Novikau, I, Nowak, S, Oberkofler, M, Ochoukov, R, Olsen, J, Orain, F, Palermo, F, Pan, O, Papp, G, Perez, I, Pau, A, Pautasso, G, Paz-Soldan, C, Petersson, P, Piovesan, P, Piron, C, Plank, U, Plaum, B, Plock, B, Plyusnin, V, Pokol, G, Poli, E, Porte, L, Putterich, T, Ramisch, M, Rasmussen, J, Ratta, G, Ratynskaia, S, Raupp, G, Refy, D, Reich, M, Reimold, F, Reiser, D, Reisner, M, Reiter, D, Ribeiro, T, Riedl, R, Riesch, J, Rittich, D, Rodriguez, J, Rocchi, G, Rodriguez-Fernandez, P, Rodriguez-Ramos, M, Rohde, V, Ronchi, G, Ross, A, Rott, M, Rubel, M, Ryan, D, Ryter, F, Saarelma, S, Salewski, M, Salmi, A, Samoylov, O, Sanchez, L, Santos, J, Sauter, O, Schall, G, Schluter, K, Schmid, K, Schmitz, O, Schneider, P, Schrittwieser, R, Schubert, M, Schuster, C, Schwarz-Selinger, T, Schweinzer, J, Seliunin, E, Shabbir, A, Shalpegin, A, Sharapov, S, Sheikh, U, Shevelev, A, Sias, G, Siccinio, M, Sieglin, B, Sigalov, A, Silva, A, Silva, C, Silvagni, D, Simpson, J, Sipila, S, Smigelskis, E, Snicker, A, Solano, E, Sommariva, C, Sozzi, C, Spizzo, G, Spolaore, M, Stegmeir, A, Stejner, M, Stober, J, Strumberge, E, Lopez, G, Sun, H, Suttrop, W, Sytova, E, Szepesi, T, Tal, B, Tala, T, Tardini, G, Tardocchi, M, Terranova, D, Teschke, M, Thoren, E, Tierens, W, Told, D, Treutterer, W, Trevisan, G, Trier, E, Tripsky, M, Usoltceva, M, Valisa, M, Valovic, M, Van Zeeland, M, Vannini, F, Vanovac, B, Varela, P, Varoutis, S, Vianello, N, Vicente, J, Verdoolaege, G, Vierle, T, Viezzer, E, Voitsekhovitch, I, Von Toussaint, U, Wagner, D, Wang, X, Weiland, M, White, A, Willensdorfer, M, Wiringer, B, Wischmeier, M, Wolf, R, Wolfrum, E, Yang, Q, Yu, Q, Zagorski, R, Zammuto, I, Zehetbauer, T, Zhang, W, Zholobenko, W, Zilker, M, Zito, A, Zohm, H, and Zoletnik, S

Subjects
Nuclear and High Energy Physics, Asdex Upgrade, confinement, ELLM-free discharges, sol, Computer science, Nuclear engineering, ALCATOR C-MOD, UPPER DIVERTOR, ASDEX Upgrade, Physics::Plasma Physics, [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], Simulació per ordinador, alcator c-mod, ddc:530, upper divertor, ELLM-free discharge, SOL, Basis (linear algebra), Physics, turbulence, transition, h-mode plasmas, Condensed Matter Physics, ddc, Informàtica::Aplicacions de la informàtica::Aplicacions informàtiques a la física i l‘enginyeria [Àrees temàtiques de la UPC], Fusion reactors, Physics and Astronomy, CONFINEMENT MODES, H-MODE PLASMAS, Physics::Space Physics, Nuclear fusion, TURBULENCE, ddc:620, confinement modes, TRANSITION
Abstract

An overview of recent results obtained at the tokamak ASDEX Upgrade (AUG) is given. A work flow for predictive profile modelling of AUG discharges was established which is able to reproduce experimental H-mode plasma profiles based on engineering parameters only. In the plasma center, theoretical predictions on plasma current redistribution by a dynamo effect were confirmed experimentally. For core transport, the stabilizing effect of fast ion distributions on turbulent transport is shown to be important to explain the core isotope effect and improves the description of hollow low-Z impurity profiles. The L–H power threshold of hydrogen plasmas is not affected by small helium admixtures and it increases continuously from the deuterium to the hydrogen level when the hydrogen concentration is raised from 0 to 100%. One focus of recent campaigns was the search for a fusion relevant integrated plasma scenario without large edge localised modes (ELMs). Results from six different ELM-free confinement regimes are compared with respect to reactor relevance: ELM suppression by magnetic perturbation coils could be attributed to toroidally asymmetric turbulent fluctuations in the vicinity of the separatrix. Stable improved confinement mode plasma phases with a detached inner divertor were obtained using a feedback control of the plasma β. The enhanced Dα H-mode regime was extended to higher heating power by feedback controlled radiative cooling with argon. The quasi-coherent exhaust regime was developed into an integrated scenario at high heating power and energy confinement, with a detached divertor and without large ELMs. Small ELMs close to the separatrix lead to peeling-ballooning stability and quasi continuous power exhaust. Helium beam density fluctuation measurements confirm that transport close to the separatrix is important to achieve the different ELM-free regimes. Based on separatrix plasma parameters and interchange-drift-Alfvén turbulence, an analytic model was derived that reproduces the experimentally found important operational boundaries of the density limit and between L- and H-mode confinement. Feedback control for the X-point radiator (XPR) position was established as an important element for divertor detachment control. Stable and detached ELM-free phases with H-mode confinement quality were obtained when the XPR was moved 10 cm above the X-point. Investigations of the plasma in the future flexible snow-flake divertor of AUG by means of first SOLPS-ITER simulations with drifts activated predict beneficial detachment properties and the activation of an additional strike point by the drifts. This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014–2018 and 2019–2020 under Grant Agreement No. 633053. The views and opinions expressed herein do not necessarily reflect those of the European Commission. Peer Reviewed "Article signat per més de 50 autors/es: U. Stroth, D. Aguiam, E. Alessi, C. Angioni, N. Arden, R. Arredondo Parra, V. Artigues, O. Asunta, M. Balden, V. Bandaru, A. Banon-Navarro, K. Behler, A. Bergmann, M. Bergmann, J. Bernardo, M. Bernert, A. Biancalani, R. Bielajew, R. Bilato, G. Birkenmeier, T. Blanken, V. Bobkov, A. Bock, T. Body, T. Bolzonella, N. Bonanomi, A. Bortolon, B. Böswirth, C. Bottereau, A. Bottino, H. van den Brand, M. Brenzke, S. Brezinsek, D. Brida, F. Brochard, C. Bruhn, J. Buchanan, A. Buhler, A. Burckhart, Y. Camenen, B. Cannas, P. Cano Megias, D. Carlton, M. Carr, P. Carvalho, C. Castaldo, M. Cavedon, C. Cazzaniga, C. Challis, A. Chankin, C. Cianfarani, F. Clairet, S. Coda, R. Coelho, J.W. Coenen, L. Colas, G. Conway, S. Costea, D. Coster, T. Cote, A.J. Creely, G. Croci, D.J. Cruz Zabala, G. Cseh, A. Czarnecka, I. Cziegler, O. D'Arcangelo, A. Dal Molin, P. David, C. Day, M. de Baar, P. de Marné, R. Delogu, S. Denk, P. Denner, A. Di Siena, J.J. Dominguez Palacios Durán, D. Dunai, A. Drenik, M. Dreval, R. Drube, M. Dunne, B.P. Duval, R. Dux, T. Eich, S. Elgeti, A. Encheva, K. Engelhardt, B. Erdös, I. Erofeev, B. Esposito, E. Fable, M. Faitsch, U. Fantz, M. Farnik, H. Faugel, F. Felici, O. Ficker, S. Fietz, A. Figueredo, R. Fischer, O. Ford, L. Frassinetti, M. Fröschle, G. Fuchert, J.C. Fuchs, H. Fünfgelder, S. Futatani, K. Galazka, J. Galdon-Quiroga, D. Gallart Escolà, A. Gallo10, Y. Gao11, S. Garavaglia3, M. Garcia Muñoz16, B. Geiger21, L. Giannone1, S. Gibson32, L. Gil2, E. Giovannozzi18, S. Glöggler1, M. Gobbin8, J. Gonzalez Martin, T. Goodman, G. Gorini, T. Görler, D. Gradic, G. Granucci, A. Gräter, H. Greuner, M. Griener, M. Groth, A. Gude, L. Guimarais, S. Günter, G. Haas, A.H. Hakola, C. Ham, T. Happel, N. den Harder, G. Harrer, J. Harrison, V. Hauer, T. Hayward-Schneider, B. Heinemann, T. Hellsten, S. Henderson, P. Hennequin, A. Herrmann, E. Heyn, F. Hitzler, J. Hobirk, K. Höfler, J.H. Holm, M. Hölzl, C. Hopf, L. Horvath, T. Höschen, A. Houben, A. Hubbard, A. Huber, K. Hunger, V. Igochine, M. Iliasova, T. Ilkei, K. Insulander Björk, C. Ionita-Schrittwieser, I. Ivanova-Stanik, W. Jacob, N. Jaksic, F. Janky, A. Jansen van Vuuren, A. Jardin, F. Jaulmes, F. Jenko, T. Jensen, E. Joffrin, A. Kallenbach, S. Kálvin, M. Kantor, A. Kappatou, O. Kardaun, J. Karhunen4, C.-P. Käsemann, S. Kasilov, A. Kendl, W. Kernbichler, E. Khilkevitch, A. Kirk, S. Kjer Hansen, V. Klevarova, G. Kocsis, M. Koleva, M. Komm, M. Kong, A. Krämer-Flecken, K. Krieger, A. Krivska, O. Kudlacek, T. Kurki-Suonio, B. Kurzan, B. Labit, K. Lackner, F. Laggner, A. Lahtinen, P.T. Lang, P. Lauber, N. Leuthold, L. Li, J. Likonen, O. Linder, B. Lipschultz, Y. Liu, A. Lohs, Z. Lu, T. Luda di Cortemiglia, N.C. Luhmann, T. Lunt, A. Lyssoivan, T. Maceina, J. Madsen, A. Magnanimo, H. Maier, J. Mailloux, R. Maingi, O. Maj, E. Maljaars, P. Manas, A. Mancini, A. Manhard, P. Mantica, M. Mantsinen, P. Manz, M. Maraschek, C. Marchetto, L. Marrelli, P. Martin, A. Martitsch, F. Matos, M. Mayer, M.-L. Mayoral, D. Mazon, P.J. McCarthy, R. McDermott, R. Merkel, A. Merle, D. Meshcheriakov, H. Meyer, D. Milanesio, P. Molina Cabrera, F. Monaco, M. Muraca, F. Nabais, V. Naulin, R. Nazikian, R.D. Nem, A. Nemes-Czopf, G. Neu, R. Neu, A.H. Nielsen, S.K. Nielsen, T. Nishizawa, M. Nocente, J.-M. Noterdaeme, I. Novikau, S. Nowak, M. Oberkofler, R. Ochoukov, J. Olsen, F. Orain, F. Palermo, O. Pan, G. Papp, I. Paradela Perez, A. Pau, G. Pautasso, C. Paz-Soldan, P. Petersson, P. Piovesan, C. Piron, U. Plank, B. Plaum, B. Plöck, V. Plyusnin, G. Pokol, E. Poli, L. Porte, T. Pütterich, M. Ramisch, J. Rasmussen, G. Ratta, S. Ratynskaia, G. Raupp, D. Réfy, M. Reich1, F. Reimold, D. Reiser, M. Reisner, D. Reiter, T. Ribeiro, R. Riedl, J. Riesch, D. Rittich, J.F. Rivero Rodriguez, G. Rocchi, P. Rodriguez-Fernandez, M. Rodriguez-Ramos, V. Rohde, G. Ronchi, A. Ross, M. Rott, M. Rubel, D.A. Ryan, F. Ryter, S. Saarelma, M. Salewski, A. Salmi, O. Samoylov, L. Sanchis Sanchez, J. Santos, O. Sauter, G. Schall, K. Schlüter, K. Schmid, O. Schmitz, P.A. Schneider, R. Schrittwieser, M. Schubert, C. Schuster, T. Schwarz-Selinger, J. Schweinzer, E. Seliunin, A. Shabbir, A. Shalpegin, S. Sharapov, U. Sheikh, A. Shevelev, G. Sias, M. Siccinio, B. Sieglin, A. Sigalov, A. Silva, C. Silva, D. Silvagni, J. Simpson, S. Sipilä, E. Smigelskis, A. Snicker, E. Solano, C. Sommariva, C. Sozzi, G. Spizzo, M. Spolaore, A. Stegmeir, M. Stejner, J. Stober, E. Strumberge1, G. Suarez Lopez, H.-J. Sun, W. Suttrop, E. Sytova, T. Szepesi, B. Tál, T. Tala, G. Tardini, M. Tardocchi, D. Terranova, M. Teschke, E. Thorén, W. Tierens, D. Told, W. Treutterer, G. Trevisan, E. Trier, M. Tripský, M. Usoltceva, M. Valisa, M. Valovic, M. van Zeeland, F. Vannini, B. Vanovac, P. Varela, S. Varoutis, N. Vianello, J. Vicente, G. Verdoolaege, T. Vierle, E. Viezzer, I. Voitsekhovitch, U. von Toussaint, D. Wagner, X. Wang, M. Weiland, A.E. White, M. Willensdorfer, B. Wiringer, M. Wischmeier, R. Wolf, E. Wolfrum, Q. Yang, Q. Yu, R. Zagórski, I. Zammuto, T. Zehetbauer, W. Zhang, W. Zholobenko, M. Zilker, A. Zito, H. Zohm, S. Zoletnik and the EUROfusion MST1 Team "

Published
2022

11. Experimental confirmation of efficient island divertor operation and successful neoclassical transport optimization in Wendelstein 7-X

Author

Thomas Sunn Pedersen, I. Abramovic, P. Agostinetti, M. Agredano Torres, S. Äkäslompolo, J. Alcuson Belloso, P. Aleynikov, K. Aleynikova, M. Alhashimi, A. Ali, N. Allen, A. Alonso, G. Anda, T. Andreeva, C. Angioni, A. Arkhipov, A. Arnold, W. Asad, E. Ascasibar, M.-H. Aumeunier, K. Avramidis, E. Aymerich, S.-G. Baek, J. Bähner, A. Baillod, M. Balden, J. Baldzuhn, S. Ballinger, M. Banduch, S. Bannmann, A. Banon Navarro, A. Bañón Navarro, T. Barbui, C. Beidler, C. Belafdil, A. Bencze, A. Benndorf, M. Beurskens, C. Biedermann, O. Biletskyi, B. Blackwell, M. Blatzheim, T. Bluhm, D. Böckenhoff, G. Bongiovi, M. Borchardt, D. Borodin, J. Boscary, H. Bosch, T. Bosmann, B. Böswirth, L. Böttger, A. Bottino, S. Bozhenkov, R. Brakel, C. Brandt, T. Bräuer, H. Braune, S. Brezinsek, K. Brunner, S. Buller, R. Burhenn, R. Bussiahn, B. Buttenschön, A. Buzás, V. Bykov, I. Calvo, K. Camacho Mata, I. Caminal, B. Cannas, A. Cappa, A. Carls, F. Carovani, M. Carr, D. Carralero, B. Carvalho, J. Casas, D. Castano-Bardawil, F. Castejon, N. Chaudhary, I. Chelis, A. Chomiczewska, J.W. Coenen, M. Cole, F. Cordella, Y. Corre, K. Crombe, G. Cseh, B. Csillag, H. Damm, C. Day, M. de Baar, E. De la Cal, S. Degenkolbe, A. Demby, S. Denk, C. Dhard, A. Di Siena, A. Dinklage, T. Dittmar, M. Dreval, M. Drevlak, P. Drewelow, P. Drews, D. Dunai, E. Edlund, F. Effenberg, G. Ehrke, M. Endler, D.A. Ennis, F.J. Escoto, T. Estrada, E. Fable, N. Fahrenkamp, A. Fanni, J. Faustin, J. Fellinger, Y. Feng, W. Figacz, E. Flom, O. Ford, T. Fornal, H. Frerichs, S. Freundt, G. Fuchert, M. Fukuyama, F. Füllenbach, G. Gantenbein, Y. Gao, K. Garcia, J.M. García Regaña, I. García-Cortés, J. Gaspar, D.A. Gates, J. Geiger, B. Geiger, L. Giudicotti, A. González, A. Goriaev, D. Gradic, M. Grahl, J.P. Graves, J. Green, E. Grelier, H. Greuner, S. Groß, H. Grote, M. Groth, M. Gruca, O. Grulke, M. Grün, J. Guerrero Arnaiz, S. Günter, V. Haak, M. Haas, P. Hacker, A. Hakola, A. Hallenbert, K. Hammond, X. Han, S.K. Hansen, J.H. Harris, H. Hartfuß, D. Hartmann, D. Hathiramani, R. Hatzky, J. Hawke, S. Hegedus, B. Hein, B. Heinemann, P. Helander, S. Henneberg, U. Hergenhahn, C. Hidalgo, F. Hindenlang, M. Hirsch, U. Höfel, K.P. Hollfeld, A. Holtz, D. Hopf, D. Höschen, M. Houry, J. Howard, X. Huang, M. Hubeny, S. Hudson, K. Ida, Y. Igitkhanov, V. Igochine, S. Illy, C. Ionita-Schrittwieser, M. Isobe, M. Jabłczyńska, S. Jablonski, B. Jagielski, M. Jakubowski, A. Jansen van Vuuren, J. Jelonnek, F. Jenko, T. Jensen, H. Jenzsch, P. Junghanns, J. Kaczmarczyk, J. Kallmeyer, U. Kamionka, M. Kandler, S. Kasilov, Y. Kazakov, D. Kennedy, A. Kharwandikar, M. Khokhlov, C. Kiefer, C. Killer, A. Kirschner, R. Kleiber, T. Klinger, S. Klose, J. Knauer, A. Knieps, F. Köchl, G. Kocsis, Ya.I. Kolesnichenko, A. Könies, R. König, J. Kontula, P. Kornejew, J. Koschinsky, M.M. Kozulia, A. Krämer-Flecken, R. Krampitz, M. Krause, N. Krawczyk, T. Kremeyer, L. Krier, D.M. Kriete, M. Krychowiak, I. Ksiazek, M. Kubkowska, M. Kuczynski, G. Kühner, A. Kumar, T. Kurki-Suonio, S. Kwak, M. Landreman, P.T. Lang, A. Langenberg, H.P. Laqua, H. Laqua, R. Laube, S. Lazerson, M. Lewerentz, C. Li, Y. Liang, Ch. Linsmeier, J. Lion, A. Litnovsky, S. Liu, J. Lobsien, J. Loizu, J. Lore, A. Lorenz, U. Losada, F. Louche, R. Lunsford, V. Lutsenko, M. Machielsen, F. Mackel, J. Maisano-Brown, O. Maj, D. Makowski, G. Manduchi, E. Maragkoudakis, O. Marchuk, S. Marsen, E. Martines, J. Martinez-Fernandez, M. Marushchenko, S. Masuzaki, D. Maurer, M. Mayer, K.J. McCarthy, O. Mccormack, P. McNeely, H. Meister, B. Mendelevitch, S. Mendes, A. Merlo, A. Messian, A. Mielczarek, O. Mishchenko, B. Missal, R. Mitteau, V.E. Moiseenko, A. Mollen, V. Moncada, T. Mönnich, T. Morisaki, D. Moseev, G. Motojima, S. Mulas, M. Mulsow, M. Nagel, D. Naujoks, V. Naulin, T. Neelis, H. Neilson, R. Neu, O. Neubauer, U. Neuner, D. Nicolai, S.K. Nielsen, H. Niemann, T. Nishiza, T. Nishizawa, C. Nührenberg, R. Ochoukov, J. Oelmann, G. Offermanns, K. Ogawa, S. Okamura, J. Ölmanns, J. Ongena, J. Oosterbeek, M. Otte, N. Pablant, N. Panadero Alvarez, A. Pandey, E. Pasch, R. Pavlichenko, A. Pavone, E. Pawelec, G. Pechstein, G. Pelka, V. Perseo, B. Peterson, D. Pilopp, S. Pingel, F. Pisano, B. Plöckl, G. Plunk, P. Pölöskei, B. Pompe, A. Popov, M. Porkolab, J. Proll, M.J. Pueschel, M.-E. Puiatti, A. Puig Sitjes, F. Purps, K. Rahbarnia, M. Rasiński, J. Rasmussen, A. Reiman, F. Reimold, M. Reisner, D. Reiter, M. Richou, R. Riedl, J. Riemann, K. Riße, G. Roberg-Clark, V. Rohde, J. Romazanov, D. Rondeshagen, P. Rong, L. Rudischhauser, T. Rummel, K. Rummel, A. Runov, N. Rust, L. Ryc, P. Salembier, M. Salewski, E. Sanchez, S. Satake, G. Satheeswaran, J. Schacht, E. Scharff, F. Schauer, J. Schilling, G. Schlisio, K. Schmid, J. Schmitt, O. Schmitz, W. Schneider, M. Schneider, P. Schneider, R. Schrittwieser, T. Schröder, M. Schröder, R. Schroeder, B. Schweer, D. Schwörer, E. Scott, B. Shanahan, G. Sias, P. Sichta, M. Singer, P. Sinha, S. Sipliä, C. Slaby, M. Sleczka, H. Smith, J. Smoniewski, E. Sonnendrücker, M. Spolaore, A. Spring, R. Stadler, D. Stańczak, T. Stange, I. Stepanov, L. Stephey, J. Stober, U. Stroth, E. Strumberger, C. Suzuki, Y. Suzuki, J. Svensson, T. Szabolics, T. Szepesi, M. Szücs, F.L. Tabarés, N. Tamura, A. Tancetti, C. Tantos, J. Terry, H. Thienpondt, H. Thomsen, M. Thumm, J.M. Travere, P. Traverso, J. Tretter, E. Trier, H. Trimino Mora, T. Tsujimura, Y. Turkin, A. Tykhyi, B. Unterberg, P. van Eeten, B.Ph. van Milligen, M. van Schoor, L. Vano, S. Varoutis, M. Vecsei, L. Vela, J.L. Velasco, M. Vervier, N. Vianello, H. Viebke, R. Vilbrandt, G. Vogel, N. Vogt, C. Volkhausen, A. von Stechow, F. Wagner, E. Wang, H. Wang, F. Warmer, T. Wauters, L. Wegener, T. Wegner, G. Weir, U. Wenzel, A. White, F. Wilde, F. Wilms, T. Windisch, M. Winkler, A. Winter, V. Winters, R. Wolf, A.M. Wright, G.A. Wurden, P. Xanthopoulos, S. Xu, H. Yamada, H. Yamaguchi, M. Yokoyama, M. Yoshinuma, Q. Yu, M. Zamanov, M. Zanini, M. Zarnstorff, D. Zhang, S. Zhou, J. Zhu, C. Zhu, M. Zilker, A. Zocco, H. Zohm, S. Zoletnik, L. Zsuga, Universitat Politècnica de Catalunya. Departament de Teoria del Senyal i Comunicacions, Universitat Politècnica de Catalunya. GPI - Grup de Processament d'Imatge i Vídeo, Universitat Politècnica de Catalunya. GREO - Grup de Recerca en Enginyeria Òptica, Pedersen, T, Abramovic, I, Agostinetti, P, Torres, M, Akaslompolo, S, Belloso, J, Aleynikov, P, Aleynikova, K, Alhashimi, M, Ali, A, Allen, N, Alonso, A, Anda, G, Andreeva, T, Angioni, C, Arkhipov, A, Arnold, A, Asad, W, Ascasibar, E, Aumeunier, M, Avramidis, K, Aymerich, E, Baek, S, Bahner, J, Baillod, A, Balden, M, Baldzuhn, J, Ballinger, S, Banduch, M, Bannmann, S, Navarro, A, Barbui, T, Beidler, C, Belafdil, C, Bencze, A, Benndorf, A, Beurskens, M, Biedermann, C, Biletskyi, O, Blackwell, B, Blatzheim, M, Bluhm, T, Bockenhoff, D, Bongiovi, G, Borchardt, M, Borodin, D, Boscary, J, Bosch, H, Bosmann, T, Boswirth, B, Bottger, L, Bottino, A, Bozhenkov, S, Brakel, R, Brandt, C, Brauer, T, Braune, H, Brezinsek, S, Brunner, K, Buller, S, Burhenn, R, Bussiahn, R, Buttenschon, B, Buzas, A, Bykov, V, Calvo, I, Mata, K, Caminal, I, Cannas, B, Cappa, A, Carls, A, Carovani, F, Carr, M, Carralero, D, Carvalho, B, Casas, J, Castano-Bardawil, D, Castejon, F, Chaudhary, N, Chelis, I, Chomiczewska, A, Coenen, J, Cole, M, Cordella, F, Corre, Y, Crombe, K, Cseh, G, Csillag, B, Damm, H, Day, C, de Baar, M, De la Cal, E, Degenkolbe, S, Demby, A, Denk, S, Dhard, C, Di Siena, A, Dinklage, A, Dittmar, T, Dreval, M, Drevlak, M, Drewelow, P, Drews, P, Dunai, D, Edlund, E, Effenberg, F, Ehrke, G, Endler, M, Ennis, D, Escoto, F, Estrada, T, Fable, E, Fahrenkamp, N, Fanni, A, Faustin, J, Fellinger, J, Feng, Y, Figacz, W, Flom, E, Ford, O, Fornal, T, Frerichs, H, Freundt, S, Fuchert, G, Fukuyama, M, Fullenbach, F, Gantenbein, G, Gao, Y, Garcia, K, Regana, J, Garcia-Cortes, I, Gaspar, J, Gates, D, Geiger, J, Geiger, B, Giudicotti, L, Gonzalez, A, Goriaev, A, Gradic, D, Grahl, M, Graves, J, Green, J, Grelier, E, Greuner, H, Gross, S, Grote, H, Groth, M, Gruca, M, Grulke, O, Grun, M, Arnaiz, J, Gunter, S, Haak, V, Haas, M, Hacker, P, Hakola, A, Hallenbert, A, Hammond, K, Han, X, Hansen, S, Harris, J, Hartfuss, H, Hartmann, D, Hathiramani, D, Hatzky, R, Hawke, J, Hegedus, S, Hein, B, Heinemann, B, Helander, P, Henneberg, S, Hergenhahn, U, Hidalgo, C, Hindenlang, F, Hirsch, M, Hofel, U, Hollfeld, K, Holtz, A, Hopf, D, Hoschen, D, Houry, M, Howard, J, Huang, X, Hubeny, M, Hudson, S, Ida, K, Igitkhanov, Y, Igochine, V, Illy, S, Ionita-Schrittwieser, C, Isobe, M, Jablczynska, M, Jablonski, S, Jagielski, B, Jakubowski, M, van Vuuren, A, Jelonnek, J, Jenko, F, Jensen, T, Jenzsch, H, Junghanns, P, Kaczmarczyk, J, Kallmeyer, J, Kamionka, U, Kandler, M, Kasilov, S, Kazakov, Y, Kennedy, D, Kharwandikar, A, Khokhlov, M, Kiefer, C, Killer, C, Kirschner, A, Kleiber, R, Klinger, T, Klose, S, Knauer, J, Knieps, A, Kochl, F, Kocsis, G, Kolesnichenko, Y, Konies, A, Konig, R, Kontula, J, Kornejew, P, Koschinsky, J, Kozulia, M, Kramer-Flecken, A, Krampitz, R, Krause, M, Krawczyk, N, Kremeyer, T, Krier, L, Kriete, D, Krychowiak, M, Ksiazek, I, Kubkowska, M, Kuczynski, M, Kuhner, G, Kumar, A, Kurki-Suonio, T, Kwak, S, Landreman, M, Lang, P, Langenberg, A, Laqua, H, Laube, R, Lazerson, S, Lewerentz, M, Li, C, Liang, Y, Linsmeier, C, Lion, J, Litnovsky, A, Liu, S, Lobsien, J, Loizu, J, Lore, J, Lorenz, A, Losada, U, Louche, F, Lunsford, R, Lutsenko, V, Machielsen, M, Mackel, F, Maisano-Brown, J, Maj, O, Makowski, D, Manduchi, G, Maragkoudakis, E, Marchuk, O, Marsen, S, Martines, E, Martinez-Fernandez, J, Marushchenko, M, Masuzaki, S, Maurer, D, Mayer, M, Mccarthy, K, Mccormack, O, Mcneely, P, Meister, H, Mendelevitch, B, Mendes, S, Merlo, A, Messian, A, Mielczarek, A, Mishchenko, O, Missal, B, Mitteau, R, Moiseenko, V, Mollen, A, Moncada, V, Monnich, T, Morisaki, T, Moseev, D, Motojima, G, Mulas, S, Mulsow, M, Nagel, M, Naujoks, D, Naulin, V, Neelis, T, Neilson, H, Neu, R, Neubauer, O, Neuner, U, Nicolai, D, Nielsen, S, Niemann, H, Nishiza, T, Nishizawa, T, Nuhrenberg, C, Ochoukov, R, Oelmann, J, Offermanns, G, Ogawa, K, Okamura, S, Olmanns, J, Ongena, J, Oosterbeek, J, Otte, M, Pablant, N, Alvarez, N, Pandey, A, Pasch, E, 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Stepanov, I, Stephey, L, Stober, J, Stroth, U, Strumberger, E, Suzuki, C, Suzuki, Y, Svensson, J, Szabolics, T, Szepesi, T, Szucs, M, Tabares, F, Tamura, N, Tancetti, A, Tantos, C, Terry, J, Thienpondt, H, Thomsen, H, Thumm, M, Travere, J, Traverso, P, Tretter, J, Trier, E, Mora, H, Tsujimura, T, Turkin, Y, Tykhyi, A, Unterberg, B, van Eeten, P, van Milligen, B, van Schoor, M, Vano, L, Varoutis, S, Vecsei, M, Vela, L, Velasco, J, Vervier, M, Vianello, N, Viebke, H, Vilbrandt, R, Vogel, G, Vogt, N, Volkhausen, C, von Stechow, A, Wagner, F, Wang, E, Wang, H, Warmer, F, Wauters, T, Wegener, L, Wegner, T, Weir, G, Wenzel, U, White, A, Wilde, F, Wilms, F, Windisch, T, Winkler, M, Winter, A, Winters, V, Wolf, R, Wright, A, Wurden, G, Xanthopoulos, P, Xu, S, Yamada, H, Yamaguchi, H, Yokoyama, M, Yoshinuma, M, Yu, Q, Zamanov, M, Zanini, M, Zarnstorff, M, Zhang, D, Zhou, S, Zhu, J, Zhu, C, Zilker, M, Zocco, A, Zohm, H, Zoletnik, S, Zsuga, L, Fusion and Plasma Physics, Department of Applied Physics, National Institute for Fusion Science, Aalto-yliopisto, Aalto University, Science and Technology of Nuclear Fusion, Group Heemels, Control Systems Technology, and Turbulence in Fusion Plasmas

Subjects
Magnetic confinement, Nuclear and High Energy Physics, Technology, Materials science, Detachment, Nuclear engineering, Física::Física de partícules [Àrees temàtiques de la UPC], Imatges -- Processament, stellarator, Divertor, Image processing, Physics::Plasma Physics, divertor, Wendelstein 7-X, ddc:530, FIS/03 - FISICA DELLA MATERIA, Neoclassical optimization, Stellarators, Reactors de fusió, magnetic confinement, Enginyeria de la telecomunicació::Processament del senyal::Processament de la imatge i del senyal vídeo [Àrees temàtiques de la UPC], Condensed Matter Physics, ddc, Fusion reactors, Physics and Astronomy, detachment, neoclassical optimization, ddc:620, ddc:600, Paper, FEC 2020 Summaries and Overviews
Abstract

We present recent highlights from the most recent operation phases of Wendelstein 7-X, the most advanced stellarator in the world. Stable detachment with good particle exhaust, low impurity content, and energy confinement times exceeding 100 ms, have been maintained for tens of seconds. Pellet fueling allows for plasma phases with reduced ion-temperature-gradient turbulence, and during such phases, the overall confinement is so good (energy confinement times often exceeding 200 ms) that the attained density and temperature profiles would not have been possible in less optimized devices, since they would have had neoclassical transport losses exceeding the heating applied in W7-X. This provides proof that the reduction of neoclassical transport through magnetic field optimization is successful. W7-X plasmas generally show good impurity screening and high plasma purity, but there is evidence of longer impurity confinement times during turbulence-suppressed phases. This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014-2018 and 2019-2020 under Grant Agreement No. 633053. Peer Reviewed Article signat per 497 autors/es: Thomas Sunn Pedersen1,2,∗ , I. Abramovic3, P. Agostinetti4, M. Agredano Torres1, S. Äkäslompolo1, J. Alcuson Belloso1, P. Aleynikov1, K. Aleynikova1, M. Alhashimi1, A. Ali1, N. Allen5, A. Alonso6, G. Anda7, T. Andreeva1, C. Angioni8, A. Arkhipov8, A. Arnold1, W. Asad8, E. Ascasibar6, M.-H. Aumeunier9, K. Avramidis10, E. Aymerich11, S.-G. Baek3, J. Bähner1, A. Baillod12, M. Balden1, M. Balden8, J. Baldzuhn1, S. Ballinger3, M. Banduch1, S. Bannmann1, A. Banon Navarro8, A. Bañon Navarro ´ 1, T. Barbui13, C. Beidler1, C. Belafdil9, A. Bencze7, A. Benndorf1, M. Beurskens1, C. Biedermann1, O. Biletskyi14, B. Blackwell15, M. Blatzheim1, T. Bluhm1, D. Böckenhoff1, G. Bongiovi16, M. Borchardt1, D. Borodin17, J. Boscary8, H. Bosch1,18, T. Bosmann19, B. Böswirth8, L. Böttger1, A. Bottino8, S. Bozhenkov1, R. Brakel1, C. Brandt1, T. Bräuer1, H. Braune1, S. Brezinsek17, K. Brunner1, S. Buller1, R. Burhenn1, R. Bussiahn1, B. Buttenschön1, A. Buzás7, V. Bykov1, I. Calvo6, K. Camacho Mata1, I. Caminal20, B. Cannas11, A. Cappa6, A. Carls1, F. Carovani1, M. Carr21, D. Carralero6, B. Carvalho22, J. Casas20, D. Castano-Bardawil17, F. Castejon6, N. Chaudhary1, I. Chelis23, A. Chomiczewska24, J.W. Coenen13,17, M. Cole1, F. Cordella25, Y. Corre9, K. Crombe26, G. Cseh7, B. Csillag7, H. Damm1, C. Day10, M. de Baar27, E. De la Cal6, S. Degenkolbe1, A. Demby13, S. Denk3, C. Dhard1, A. Di Siena8,28, A. Dinklage12, T. Dittmar17, M. Dreval14, M. Drevlak1, P. Drewelow1, P. Drews17, D. Dunai7, E. Edlund3, F. Effenberg29, G. Ehrke1, M. Endler1, D.A. Ennis5, F.J. Escoto6, T. Estrada6, E. Fable8, N. Fahrenkamp1, A. Fanni11, J. Faustin1, J. Fellinger1, Y. Feng1, W. Figacz4, E. Flom13, O. Ford1, T. Fornal24, H. Frerichs13, S. Freundt1, G. 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Maisano-Brown3, O. Maj8, D. Makowski49, G. Manduchi50, E. Maragkoudakis6, O. Marchuk17, S. Marsen1, E. Martines4, J. Martinez-Fernandez6, M. Marushchenko1, S. Masuzaki41, D. Maurer5, M. Mayer8, K.J. McCarthy6, O. Mccormack4, P. McNeely1, H. Meister8, B. Mendelevitch8, S. Mendes1, A. Merlo1, A. Messian26, A. Mielczarek49, O. Mishchenko1, B. Missal1, R. Mitteau9, V.E. Moiseenko14, A. Mollen1, V. Moncada9, T. Mönnich1, T. Morisaki41, D. Moseev1, G. Motojima41, S. Mulas6, M. Mulsow1, M. Nagel1, D. Naujoks1, V. Naulin35, T. Neelis19, H. Neilson29, R. Neu8, O. Neubauer17, U. Neuner1, D. Nicolai17, S.K. Nielsen35, H. Niemann1, T. Nishiza1, T. Nishizawa1, T. Nishizawa8, C. Nührenberg1, R. Ochoukov8, J. Oelmann17, G. Offermanns17 K. Ogawa41, S. Okamura41, J. Ölmanns17, J. Ongena26, J. Oosterbeek1, M. Otte1, N. Pablant29, N. Panadero Alvarez6, N. Panadero Alvarez6, A. Pandey1, E. Pasch1, R. Pavlichenko14, A. Pavone1, E. Pawelec46, G. Pechstein1, G. Pelka24, V. Perseo1, B. Peterson41, D. Pilopp1, S. Pingel1, F. Pisano11, B. Plöckl8, G. Plunk1, P. Pölöskei1, B. Pompe2, A. Popov51, M. Porkolab3, J. Proll19, M.J. Pueschel19,27, M.-E. Puiatti52, A. Puig Sitjes1, F. Purps1, K. Rahbarnia1, M. Rasinski ´ 17, J. Rasmussen35, A. Reiman29, F. Reimold1, M. Reisner8, D. Reiter17, M. Richou9, R. Riedl8, J. Riemann1, K. Riße1, G. Roberg-Clark1, V. Rohde8, J. Romazanov17, D. Rondeshagen1, P. Rong1, L. Rudischhauser1, T. Rummel1, K. Rummel1, A. Runov1, N. Rust1, L. Ryc24, P. Salembier20, M. Salewski35, E. Sanchez6, S. Satake41, G. Satheeswaran17, J. Schacht1, E. Scharff1, F. Schauer8, J. Schilling1, G. Schlisio1, K. Schmid8, J. Schmitt5, O. Schmitz13, W. Schneider1, M. Schneider1, P. Schneider8, R. Schrittwieser42, T. Schröder1, M. Schröder1, R. Schroeder1, B. Schweer26, D. Schwörer1, E. Scott1, E. Scott8, B. Shanahan1, G. Sias11, P. Sichta29, M. Singer1, P. Sinha29, S. Sipliä34, C. Slaby1, M. Sleczka53, H. Smith1, J. Smoniewski54, E. Sonnendrücker8, M. Spolaore4, A. Spring1, R. Stadler8, D. Stanczak24, T. Stange1, I. Stepanov26, L. Stephey13, J. Stober8, U. Stroth8,55, E. Strumberger8, C. Suzuki41, Y. Suzuki41, J. Svensson1, T. Szabolics7, T. Szepesi7, M. Szücs7, F.L. Tabares6, N. Tamura41, A. Tancetti35, C. Tantos10, J. Terry3, H. Thienpondt6, H. Thomsen1, M. Thumm10, J.M. Travere9, P. Traverso5, J. Tretter8, E. Trier8, H. Trimino Mora1, T. Tsujimura41, Y. Turkin1, A. Tykhyi45, B. Unterberg17, P. van Eeten1, B.Ph. van Milligen6, M. van Schoor26, L. Vano1, S. Varoutis10, M. Vecsei7, L. Vela56, J.L. Velasco6, M. Vervier17, N. Vianello50, H. Viebke1, R. Vilbrandt1, G. Vogel8, N. Vogt1, C. Volkhausen1, A. von Stechow1, F. Wagner1, E. Wang17, H. Wang57, F. Warmer1, T. Wauters26, L. Wegener1, T. Wegner1, G. Weir1, U. Wenzel1, A. White3, F. Wilde1, F. Wilms1, T. Windisch1, M. Winkler1, A. Winter1, V. Winters1, R. Wolf118, A.M. Wright29, G.A. Wurden39, P. Xanthopoulos1, S. Xu17, H. Yamada58, H. Yamaguchi41, M. Yokoyama41, M. Yoshinuma41, Q. Yu8, M. Zamanov14, M. Zanini1, M. Zarnstorff29, D. Zhang1, S. Zhou17, J. Zhu1, C. Zhu29, M. Zilker8, A. Zocco1, H. Zohm8, S. Zoletnik7 and L. Zsuga7 // 1 Max Planck Institute for Plasma Physics, Garching and Greifswald, Germany: 2 University of Greifswald, Greifswald, Germany; 3 Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA 02139, United States of America; 4 Consorzio RFX, Corso Stati Uniti, 4-35127 Padova, Italy; 5 Auburn University, Auburn, AL 36849, United States of America; 6 CIEMAT, Avenida Complutense, 40, 28040 Madrid, Spain; 7 Center for Energy Research, Konkoly-Thegeut 29-33, 1121 Budapest, Hungary; 8 Max-Planck-Institute for Plasma Physics, Boltzmannstraße 2, 85748 Garching bei München, Germany; 9 CEA Cadarache, 13115 Saint-Paul-lez-Durance, France; 10 Karlsruhe Institute of Technology, Kaiserstr. 12, 76131 Karlsruhe, Germany; 11 University of Cagliari, Via Universita, 40, 09124 Cagliari, Italy; 12 École Polytechnique Fédérale de Lausanne, Swiss Plasma Center, CH-1015 Lausanne, Switzerland; 13 University of Wisconsin–Madison, Engineering Drive, Madison, WI 53706, United States of America; 14 Institute of Plasma Physics, National Science Center ‘Kharkiv Institute of Physics and Technology’, Kharkiv, Ukraine; 15 The Australian National University, Acton ACT 2601, Canberra, Australia; 16 Department of Engineering, University of Palermo, Viale delle Scienze, Edificio 6, Palermo, 90128, Italy; 17 Forschungszentrum Jülich GmbH, Institut für Energie-und Klimaforschung—Plasmaphysik, 52425 Jülich, Germany; 18 Technical University of Berlin, Strasse des 17. Juni 135, 10623 Berlin, Germany; 19 Eindhoven University of Technology, 5600 MB Eindhoven, Netherlands; 20 Universitat Politècnica de Catalunya. BarcelonaTech, C. Jordi Girona, 31, 08034 Barcelona, Spain; 21 Culham Center for Fusion Energy, Abingdon OX14 3EB, United Kingdom; 22 Instituto de Plasmas e Fusao Nuclear, Av. Rovisco Pais, 1049-001 Lisboa, Portugal; 23 Department of Physics, National and Kapodistrian University of Athens, 15784 Athens, Greece; 24 Institute of Plasma Physics and Laser Microfusion, 23 Hery Str., 01-497 Warsaw, Poland; 25 ENEA—Centro Ricerche Frascati, Via Enrico Fermi, 45, 00044 Frascati RM, Italy; 26 Laboratory for Plasma Physics, LPP-ERM/KMS, TEC Partner, B-1000 Brussels, Belgium; 27 Dutch Institute for Fundamental Energy Research, PO Box 6336, 5600 HH Eindhoven, Netherlands; 28 University of Texas, Austin, TX, United States of America; 29 Princeton Plasma Physics Laboratory, Princeton, NJ 08543, United States of America; 30 Kyushu University, 744 Motooka Nishi-ku, Fukuoka 819-0395, Japan; 31 Aix-Marseille University, Jardin du Pharo, 58 Boulevard Charles Livon, 13007, Marseille, France; 32 Department of Physics and Astronomy, Padova University, Via Marzolo 8, 35131 Padova, Italy; 33 Department of Applied Physics, Ghent University, Sint-Pietersnieuwstraat 41 B4, 9000 Ghent, Belgium; 34 Aalto University, 02150 Espoo, Finland; 35 Department of Physics, Technical University of Denmark, Anker Engelunds Vej, 2800 Kgs Lyngby, Denmark; 36 VTT Technical Research Center of Finland Ltd., PO Box 1000, FI-02044 VTT, Finland; 37 Institute of Plasma Physics, Chinese Academy of Sciences, 230031 Hefei, Anhui, China; 38 Oak Ridge National Laboratory, 1 Bethel Valley Rd, Oak Ridge, TN 37830, United States of America; 39 Los Alamos National Laboratory, NM 87545, United States of America; 40 Fritz-Haber-Institut der Max-Planck-Gesellschaft, 14195 Berlin, Germany; 41 National Institute for Fusion Science, National Institutes of Natural Sciences, 322-6 Oroshi-cho, Toki, Gifu Prefecture 509-5292, Japan; 42 Institute for Ion Physics and Applied Physics, University of Innsbruck, Innsbruck, Austria; 43 Graz University of Technology, Rechbauerstraße 12, 8010 GRAZ, Austria; 44 Austrian Academy of Science, Doktor-Ignaz-Seipel-Platz 2, 1010 Wien, Austria; 45 Institute for Nuclear Research, prospekt Nauky 47, Kyiv 03028, Ukraine; 46 University of Opole, plac Kopernika 11a, 45-001 Opole, Poland; 47 University of Maryland, Paint Branch Drive, College Park, MA 20742, United States of America; 48 National Research Nuclear University MEPhI, 115409 Moscow, Russian Federation; 49 Department of Microelectronics and Computer Science, Lodz University of Technology, Wolczanska 221/223, 90-924 Lodz, Poland; 50 Consiglio Nazionale delle Ricerche, Piazzale Aldo Moro, 7, 00185 Roma, Italy; 51 Ioffe Physical-Technical Institute of the Russian Academy of Sciences, 26 Politekhnicheskaya, St Petersburg 194021, Russian Federation; 52 Istituto di Fisica del Plasma Piero Caldirola, Via Roberto Cozzi, 53, 20125 Milano, Italy; 53 University of Szczecin, 70-453, aleja Papieza Jana Pawła II 22A, Szczecin, Poland; 54 Lawrence University, 711 E Boldt Way, Appleton, WI 54911, United States of America; 55 Physik-Department E28, Technische Universität München, 85747 Garching, Germany; 56 Universidad Carlos III de Madrid, Av. de la Universidad, 30 Madrid, Spain; 57 Yale University, New Haven, CT 06520, United States of America; 58 University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chhiab 277-0882, Japan Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant::7.a - Per a 2030, augmentar la cooperació internacional per tal de facilitar l’accés a la investigació i a les tecnolo­gies energètiques no contaminants, incloses les fonts d’energia renovables, l’eficiència energètica i les tecnologies de combustibles fòssils avançades i menys contaminants, i promoure la inversió en infraestructures energètiques i tecnologies d’energia no contaminant

Published
2022
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12. A hot steam leak during baking of ASDEX Upgrade – Consequences and lessons learned

Author

S. Vorbrugg, A. Herrmann, D. Bösser, K. Hegele, T. Vierle, V. Rohde, G. Schall, J. Stober, M. Balden, K. Hunger, and ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society

Subjects
Leak, Tokamak, Mechanical Engineering, Nuclear engineering, Water cooled, food and beverages, 01 natural sciences, 010305 fluids & plasmas, law.invention, Nuclear Energy and Engineering, ASDEX Upgrade, law, 0103 physical sciences, Boron containing, Water cooling, Environmental science, General Materials Science, 010306 general physics, Shut down, Civil and Structural Engineering
Abstract

ASDEX Upgrade is a midsize tokamak operated since 1991. A scheduled maintenance and enhancement shut down is done about once a year. After pump down and leak search a baking procedure is started to condition the vacuum vessel for plasma operation. During operation the vacuum vessel and all in-vessel components are water cooled. This cooling system is also used for baking with hot water at 150 °C. During one of these regular baking periods a hot steam leak appears in November 2017. The detection of the leak has triggered a controlled cool down scenario. Nevertheless, between the appearance of the leak and the identification and closing about 100 L water escaped during the controlled cool down from 150 °C to 65 °C into the torus. A fraction of the hot water was distributed as steam all over the torus and condensed at the coldest parts of the vessel, preferentially in remote ports. In addition, the steam interacts with boron containing layers. The resulting acid steam caused additional erosion. The paper presents details of damages, actions taken to remove them as well as measures taken to avoid a future steam leak.

Published
2021

13. Microwave diagnostics damage by parametric decay instabilities during electron cyclotron resonance heating in ASDEX Upgrade

Author

K. Höfler, R. Fischer, A. S. Jacobsen, M. Maraschek, Stefan Kragh Nielsen, M. Willensdorfer, S. K. Hansen, EUROfusion Mst Team, M. G. Dunne, J. Stober, EUROfusion MST1 Team, and ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society

Subjects
Physics, Microwave spikes, Wave trapping, PDI, Condensed Matter Physics, Electron cyclotron resonance, ECRH, ddc, Nuclear physics, Nuclear Energy and Engineering, ASDEX Upgrade, Physics::Plasma Physics, ITER, Microwave diagnostics, Microwave, Parametric statistics
Abstract

We present observations of microwave diagnostics damage in three discharges employing third-harmonic X-mode electron cylcotron resonance heating (ECRH) at the ASDEX Upgrade tokamak. In all cases, the diagnostics damage is explainable in terms of a parametric decay instability (PDI), where an X-mode ECRH wave decays to two trapped upper hybrid (UH) waves near half the ECRH frequency, followed by secondary instabilities, which generate strong microwave signals near multiples of half the ECRH frequency that cause the damage. Trapping of the UH waves near half the ECRH frequency is necessary to reduce the ECRH power required for exciting the PDIs to a level attainable at ASDEX Upgrade, and may occur when the second-harmonic UH resonance of the ECRH waves is present in a region of non-monotonic electron density, e.g. near the O-point of a magnetohydrodynamic mode or the plasma center. The diagnostics damage in the three discharges may be attributed to PDIs occurring near the O-point of a rotating mode, near the plasma center, and near the O-point of a locked mode, respectively. In the rotating mode case, the strong signals are shown to be quasi-periodic, with spikes occurring when the O-point of the mode passes through an ECRH beam, as expected. In the locked mode case, Thomson scattering profiles demonstrate the possibility of the primary PDI occurring based on experimental data for the first time under fusion-relevant conditions. Applying the framework used for ASDEX Upgrade to the X-mode ECRH scenarios planned for the early operation phase of ITER, the PDIs are found to be likely in connection with 170 GHz ECRH of half field scenarios and 104 GHz (or 110 GHz) ECRH of one third field scenarios. Finally, several strategies for mitigating diagnostics damage are proposed.

Published
2021

14. The upgraded ASDEX Upgrade contribution to the ITPA confinement database: description and analysis

Author

F. Ryter, C. Angioni, G. Tardini, G. Birkenmeier, P. David, M. Dunne, R. Fischer, T. Pütterich, J. Schweinzer, J. Stober, The ASDEX Upgrade Team, The EUROfusion MST1 Team, ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society, and EUROfusion MST1 Team

Subjects
Nuclear and High Energy Physics, Materials science, ASDEX Upgrade, Nuclear engineering, 0103 physical sciences, ITPA, 010306 general physics, Condensed Matter Physics, 01 natural sciences, 010305 fluids & plasmas
Abstract

The ITPA multi-machine confinement database has been recently extended, in particular to account for the effect of the metallic plasma facing components installed in the ASDEX Upgrade and JET tokamaks during the last decade. Confinement data from the ASDEX Upgrade tokamak have been contributed to the ITPA confinement database since 1994. The present version, which includes data from 1994 to 2017, is described and discussed in this article. The aim of this work is to document the database before it is made public and report on the main results on the confinement properties reflected in this database. Through the transition from carbon to metallic wall, the operation at low density originally accessible with the carbon wall, has been strongly limited by the occurrence of tungsten accumulation. However, at medium and high densities, the confinement properties with the carbon and metallic walls are rather similar. The database analysis yields in both cases a rather strong plasma current dependence and a clearly negative magnetic field dependence. The density dependence is negligible, while the well-known positive impact of triangularity appears very clearly. These dependences are partly at variance with the widely-used IPB98(y,2) confinement scaling, but in agreement with the analysis of the upgraded ITPA multi-machine and JET databases. The confinement degradation observed at high density with strong gas puffing can be clearly attributed to the density profile in the outer plasma region, as reported in previous studies.

Published
2021
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15. Two-Frequency Notch Filters for Sub-THz Plasma Diagnostics

Author

F. Leuterer, W. Kasparek, Manfred Thumm, Tobias Ruess, J. Stober, D. Wagner, and F. Monaco

Subjects
Physics, Waveguide (electromagnetism), business.industry, Frequency band, Electron cyclotron resonance, law.invention, Resonator, Narrowband, Optics, Physics::Plasma Physics, law, Gyrotron, Insertion loss, Plasma diagnostics, business
Abstract

Modern Electron Cyclotron Resonance Heating (ECRH) systems in fusion plasma research take advantage of multi-frequency gyrotrons. This means that the frequency band of some millimeter-wave diagnostics contains more than one narrowband gyrotron-frequency line, which needs to be suppressed. Compact standard-waveguide notch filters, based on coupled waveguide resonators with rectangular cross section, are presented, which can provide very high suppression of several gyrotron frequencies providing low insertion loss in the pass band.

Published
2021

16. Studies of EC pre-ionization in DIII-D to support development of ITER plasma initiation

Author

J. Sinha, P.C. de Vries, M.L. Walker, D.J. Battaglia, F. Turco, A. Hyatt, H.T. Kim, J. Stober, R. Yoneda, Y. Gribov, S.R. Haskey, I. Bykov, E. Hollmann, J.L. Herfindal, F. Glass, J. Chen, A. McLean, null the DIII-D Team, and DIII-D Team

Subjects
Nuclear and High Energy Physics, Condensed Matter Physics
Abstract

New experiments have been conducted at DIII-D to improve the physics understanding of plasma initiation assisted by electron cyclotron (EC) wave injection, allowing better extrapolation to ITER. This has been achieved by applying an EC pulse prior to start of the inductive plasma initiation (i.e. the generation of a loop voltage). A pre-plasma was formed during the EC pulse that was characterized in terms of the maximum density and temperature. Parametric scans were performed to study the influence of the EC injected power, EC injection angle, and pre-fill gas pressure on the pre-plasma creation process. These experiments showed that pre-ionized plasma of good quality can have a significant effect on the subsequent V loop induced plasma initiation process, i.e. a high density pre-plasma, increases the plasma current rise and speed at which ionization is achieved when the V loop is applied. A good quality pre-plasma is one that achieved a significant degree of ionization, mainly obtained by providing sufficient ECH power in DIII-D of the order of 1 MW. It was found that a minimum EC power of 0.5 MW was required in DIII-D to create ionization, and this would scale to a minimum power of roughly 6.5 MW for ITER.

Published
2022

17. Improvement of the Power Handling Capability of the Upgraded Multi-Frequency ECRH System at ASDEX Upgrade

Author

A. V. Chirkov, F. Leuterer, Burkhard Plaum, Andreas Meier, M. Schubert, E. M. Tai, L. G. Popov, Gregory G. Denisov, M. Münich, J. Stober, G. Gantenbein, H. Zohm, D. Wagner, T.A. Scherer, A. Zach, Carsten Lechte, V.E. Myasnikov, Manfred Thumm, W. Kasparek, V. O. Nichiporenko, F. Monaco, Dirk Strauss, John Jelonnek, M. Kircher, E. A. Solyanova, Aleksandr Grigorievich Litvak, V. I. Malygin, and ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society

Subjects
010302 applied physics, Materials science, Tokamak, Maximum power principle, Nuclear engineering, Pulse duration, 01 natural sciences, Electron cyclotron resonance, law.invention, 010309 optics, Electricity generation, Electric power transmission, Transmission (telecommunications), ASDEX Upgrade, law, 0103 physical sciences
Abstract

8 gyrotrons are in routine operation in the Electron Cyclotron Resonance, !!eating (ECRH) system at the ASDEX Upgrade tokamak. All gyrotrons are step-tunable operating at 105 and 140 GHz with a maximum output power of about 1 MW and 10 s pulse length. The system includes 8 transmission lines, mainly consisting of oversized corrugated waveguides (I.D. = 87 mm) with overall lengths between 50 and 70 meters including quasi-optical sections at both ends. The transmission lines are operating in air and transmission at maximum power levels was limited by arcing in the past. Several measures led to a significant improvement of the power handling capability of the transmission lines.

Published
2020

18. Exploring fusion-reactor physics with high-power electron cyclotron resonance heating on ASDEX Upgrade

Author

W. Suttrop, C. Angioni, T.A. Scherer, R. Fischer, L. G. Popov, E. M. Tai, A. Bock, Tobias Görler, Mst Team, V. Igochine, A. Meier, Emanuele Poli, M. Reisner, V. Nichiporenko, Th. Pütterich, V. Bobkov, M. Münich, G. G. Denisov, G. Gantenbein, F. Leuterer, Manfred Thumm, M. Schubert, W. Kasparek, A. Banon Navarro, E. Fable, B. Plaum, R. M. McDermott, Aleksandr Grigorievich Litvak, F. Monaco, J. Stober, H. Zohm, D. Wagner, L. Gil, U. Plank, MST1 Team, and ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society

Subjects
Technology, Tokamak, Cyclotron, high-beta, 7. Clean energy, 01 natural sciences, Electron cyclotron resonance, Resonant magnetic perturbations, 010305 fluids & plasmas, law.invention, ASDEX Upgrade, law, 0103 physical sciences, 010306 general physics, Physics, Plasma, Fusion power, Condensed Matter Physics, Neutral beam injection, Computational physics, ECRH, q-profile, Nuclear Energy and Engineering, ECCD, non-inductive, ddc:600
Abstract

The electron cyclotron resonance heating (ECRH) system of the ASDEX Upgrade tokomak has been upgraded over the last 15 years from a 2 MW, 2 s, 140 GHz system to an 8 MW, 10 s, dual frequency system (105/140 GHz). The power exceeds the L/H power threshold by at least a factor of two, even for high densities, and roughly equals the installed ion cyclotron range of frequencies power. The power of both wave heating systems together (>10 MW in the plasma) is about half of the available neutral beam injection (NBI) power, allowing significant variations of torque input, of the shape of the heating profile and of Qe/Qi, even at high heating power. For applications at a low magnetic field an X3-heating scheme is routinely in use. Such a scenario is now also forseen for ITER to study the first H-modes at one third of the full field. This versatile system allows one to address important issues fundamental to a fusion reactor: H-mode operation with dominant electron heating, accessing low collisionalities in full metal devices (also related to suppression of edge localized modes with resonant magnetic perturbations), influence of Te/Ti and rotational shear on transport, and dependence of impurity accumulation on heating profiles. Experiments on all these subjects have been carried out over the last few years and will be presented in this contribution. The adjustable localized current drive capability of ECRH allows dedicated variations of the shape of the q-profile and the study of their influence on non-inductive tokamak operation (so far at q 95 > 5.3). The ultimate goal of these experiments is to use the experimental findings to refine theoretical models such that they allow a reliable design of operational schemes for reactor size devices. In this respect, recent studies comparing a quasi-linear approach (TGLF) with fully non-linear modeling (GENE) of non-inductive high-beta plasmas will be reported.

Published
2020
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19. A compact two-frequency notch filter for millimeter wave plasma diagnostics

Author

J. Stober, F. Monaco, Tobias Ruess, D. Wagner, Manfred Thumm, F. Leuterer, and W. Kasparek

Subjects
Physics, Technology, Waveguide (electromagnetism), Radiation, 010308 nuclear & particles physics, business.industry, Magnetic confinement fusion, Condensed Matter Physics, Band-stop filter, 01 natural sciences, 010305 fluids & plasmas, law.invention, 621.3, Optics, law, Gyrotron, 0103 physical sciences, Extremely high frequency, Insertion loss, Plasma diagnostics, Electrical and Electronic Engineering, business, ddc:600, Instrumentation, Passband
Abstract

Sensitive millimeter wave diagnostics in magnetic confinement plasma fusion experiments need protection from gyrotron stray radiation in the plasma vessel. Modern electron cyclotron resonance heating (ECRH) systems take advantage of multi-frequency gyrotrons. This means that the frequency band of some millimeter wave diagnostics contains more than one narrow-band gyrotron-frequency line, which needs to be effectively suppressed. A compact standard waveguide notch filter based on coupled waveguide resonators with rectangular cross-section is presented which can provide very high suppression of several gyrotron frequencies and has low insertion loss of the passband., Projekt DEAL

Published
2020

20. Momentum-space-resolved measurements using oblique electron cyclotron emission for the validation of the quasi-linear theory of electron cyclotron current drive

Author

S. S. Denk, J. Hobirk, T. Luda di Cortemiglia, M. Willensdorfer, U. Stroth, Stefan Kragh Nielsen, Morten Stejner, R. Fischer, J. Stober, Emanuele Poli, J. J. Rasmussen, Omar Maj, W. Suttrop, E. Westerhof, and ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society

Subjects
Electron cyclotron emission, Physics, Tokamak, Cyclotron, Electron cyclotron current drive, Electron, Plasma, Fusion power, Condensed Matter Physics, 7. Clean energy, 01 natural sciences, Electron cyclotron resonance, 010305 fluids & plasmas, law.invention, Computational physics, ddc, Distribution function, Nuclear Energy and Engineering, ASDEX Upgrade, Physics::Plasma Physics, law, Non-thermal electron velocity distribution, 0103 physical sciences, 010306 general physics
Abstract

Electron cyclotron resonance heating (ECRH) can drive large current densities through electron cyclotron current drive (ECCD). ECCD is expected to be crucial for high-performance plasmas in future fusion reactors like ITER and DEMO, making the current drive efficiency of ECCD a critical design parameter for future reactors. In present-day devices, good agreement between measured and predicted current drive efficiency has been found. However, to ensure the reliability in future machines, a direct validation of the electron momentum distribution function is needed. As a first step towards this goal, we present in this paper oblique ECE measurements of a low-density plasma in the ASDEX Upgrade tokamak. Two oblique ECE diagnostics are used to allow the simultaneous measurements of electrons streaming co- and counter-directionally with the plasma current. Predictions for the distribution function are computed with the bounce-averaged Fokker-Planck code RELAX (E. Westerhof et al., Rijnhuizen report,1992). To allow direct comparison with the measurements, synthetic radiation temperatures are computed with the code ECRad (S. Denk et al., Computer Physics Communications, p. 107175, 2020). Good agreement is found if radial transport occurring predominantly at low electron energies is included. We demonstrate that the oblique ECE diagnostics measure the electron distribution function directly at the ECRH deposition site in phase space. Furthermore, they are sensitive to the abundance of pitch-angle scattered electrons that reduce the ECCD efficiency. Limitations and uncertainties of the measurements and the modeling are discussed.

Published
2020

21. Increased core ion temperatures in high-beta advanced scenarios in ASDEX upgrade

Author

R. Fischer, A. Di Siena, M. Reisner, A. Banon Navarro, J. Stober, A. Bock, R. M. McDermott, E. Fable, V. Bobkov, and ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society

Subjects
Physics, Nuclear and High Energy Physics, Plasma heating, Nuclear engineering, Ion temperature, Condensed Matter Physics, 01 natural sciences, 010305 fluids & plasmas, Ion, Bootstrap current, Core (optical fiber), ASDEX Upgrade, Beta (plasma physics), 0103 physical sciences, 010306 general physics
Published
2020
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23. Beam tracing study for design and operation of two-pass electron cyclotron heating at ASDEX Upgrade

Author

Carsten Lechte, Emanuele Poli, M. Schubert, S. Vorbrugg, F. Monaco, Albrecht Herrmann, B. Petzold, F. Leuterer, Burkhard Plaum, J. Stober, D. Wagner, and W. Kasparek

Subjects
Materials science, business.industry, Physics, QC1-999, Cyclotron, Grating, 7. Clean energy, 01 natural sciences, Electron cyclotron resonance, 010305 fluids & plasmas, law.invention, Optics, ASDEX Upgrade, law, Gyrotron, 0103 physical sciences, Physics::Accelerator Physics, Beam dump, 010306 general physics, business, Beam (structure), Gaussian beam
Abstract

The electron cyclotron resonance heating system at ASDEX Upgrade (AUG) is currently being extended to eight similar Gyrotrons in total. Each Gyrotron operates at 105 and 140 GHz and is designed for up to 1 MW millimetre wave output power. A substantial part of the AUG program will focus on experimental conditions, where the plasma density may be above the X-2 cut-off density at 140 GHz. In order to cope with the high density, the heating system will operate in the O-2 mode scheme with potentially incomplete absorption in the first pass. Reflecting gratings installed into the heat shield on AUG’s inner column allow for a controlled second pass of the beam’s unabsorbed fraction. Thermocouple measurements serve to control the beam position on the grating. The beam geometry is being finalized for the launchers #1-4. Beam propagation is simulated with the TORBEAM code and previous high density experiments are used as a database. The geometry is optimized using three criteria: central deposition, high absorption and robustness of the beam dump after the second pass. The experimental conditions, and the plasma electron density in particular, may vary such that the Gaussian beam parameters of the incoming beam on the grating deviate from the design values. It is proposed to model the effect of the grating with an equivalent ellipsoidal mirror. Laboratory measurements are shown, which support this model.

Published
2019
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24. The role of the source versus the collisionality in predicting a reactor density profile as observed on ASDEX Upgrade discharges

Author

J. Stober, H. Zohm, T. Puetterich, G. D. Conway, R. Bilato, Mattia Siccinio, R. M. McDermott, E. Fable, V. Bobkov, W. Suttrop, C. Angioni, T. Goerler, M. Teschke, and ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society

Subjects
Physics, Nuclear and High Energy Physics, Tokamak, Nuclear engineering, Extrapolation, Plasma, Fusion power, Parameter space, Collisionality, Condensed Matter Physics, 01 natural sciences, 7. Clean energy, 010305 fluids & plasmas, law.invention, ASDEX Upgrade, Heat flux, Physics::Plasma Physics, law, 0103 physical sciences, 010306 general physics
Abstract

The design and optimization of a future tokamak fusion reactor, from the point of view of the plasma performance and output fusion power, requires the understanding of the underlying physics and the validation on present experiments of the theory-based tools used for the predictions. Present experimental efforts are devoted to approach reactor-relevant parameters (collisionality, , normalized heat fluxes and sources, temperatures ratio) as much as possible. In this work a series of discharges performed on ASDEX Upgrade are presented, where plasma density and auxiliary power levels are scanned to cover a parameter space that moves towards reactor relevant parameters. On this dedicated discharge dataset, a first-principle-based model is then applied for validation. The degree of agreement between code results and experimental measurements is shown and discussed. In cases where discrepancy is found, possible causes are identified. It is shown that the employed modeling tool can predict the overall trend, consistent with more fundamental theoretical considerations, although quantitative extrapolation still has to be performed with care. Key results of this work show that the density peaking is mainly sustained by turbulence, with a minor role for the fueling source, and how this experimental demonstration is important to predict future reactor density profiles. Moreover, the role of electromagnetic effects is also pointed out.

Published
2019
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25. Completion of the 8 MW Multi-Frequency ECRH System at ASDEX Upgrade

Author

M. Kircher, M. Schubert, E. A. Solyanova, F. Leuterer, Andreas Meier, Burkhard Plaum, Dirk Strauss, Aleksandr Grigorievich Litvak, Carsten Lechte, V. E. Myasnikov, T.A. Scherer, L. G. Popov, E. M. Tai, John Jelonnek, G. G. Denisov, V. I. Malygin, G. Gantenbein, M. Münich, Manfred Thumm, J. Stober, H. Zohm, D. Wagner, W. Kasparek, A. V. Chirkov, V. O. Nichiporenko, F. Monaco, A. Zach, and ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society

Subjects
010302 applied physics, Technology, Tokamak, Materials science, business.industry, Terahertz radiation, Pulse duration, 01 natural sciences, Electron cyclotron resonance, law.invention, Power (physics), 010309 optics, Optics, Electric power transmission, Electricity generation, ASDEX Upgrade, law, 0103 physical sciences, business, ddc:600
Abstract

Over the last 15 years, the Electron Cyclotron Resonance Heating (ECRH) system at the ASDEX Upgrade tokamak has been upgraded from a 2 MW, 2 s, 140 GHz system to an 8 MW, 10 s, dual frequency system (105/140 GHz). Eight gyrotrons were in routine operation during the current experimental campaign. All gyrotrons are step-tunable operating at 105 and 140 GHz with a maximum output power of about 1 MW and 10 s pulse length. The system includes 8 transmission lines, mainly consisting of oversized corrugated waveguides (I.D. = 87 mm) with overall lengths between 50 and 70 meters including quasi-optical sections at both ends. Further improvements of the transmission lines with respect to power handling and reliability are underway.

Published
2019

26. Dependence on plasma shape and plasma fueling for small edge-localized mode regimes in TCV and ASDEX Upgrade

Author

V. Piergotti, F. Pesamosca, Bogdan Hnat, A. Sperduti, A. Krivska, J. Vicente, Panagiotis Tolias, Emanuele Poli, Matthias Hoelzl, Benedikt Geiger, A. Jardin, J. Ayllon-Guerola, G. Apruzzese, T. Lunt, J. Galdon-Quiroga, Riccardo Maggiora, M. Tardocchi, M. Koubiti, T. Jonsson, Bruce Lipschultz, P. Innocente, A. Gude, I Miron, M. G. Dunne, G. F. Harrer, A. Moro, A. Iantchenko, K. Galazka, P. Poloskei, K. Bogar, Roberto Ambrosino, G. Ferr, Vladimir E. Moiseenko, Istvan Cziegler, L. Guimarais, S. Vartanian, B. Erds, G. Pucella, V. Bobkov, James Buchanan, Raffaele Albanese, Harry M. Meyer, D. Boeyaert, G. F. Matthews, Eva Macusova, V. S. Marchenko, R. Zagórski, J. Buermans, A. Fil, W. Zhang, Giuseppe Gorini, B. Tal, D. Zaloga, Hugo Bufferand, A. Romano, L. Colas, J. Zebrowski, M. Weiland, L. Barrera-Orte, Matjaž Panjan, A.J. Thornton, E. Wolfrum, Miglena Dimitrova, R. M. McDermott, R. Lombroni, O. Tudisco, F. Reimold, E. R. Solano, X. Feng, Petra Bilkova, M. Groth, E. Alessi, D. S. Gahle, Olivier Février, I. Voitsekhovitch, Matthew Carr, A. Bock, O. Vasilovici, C. Ham, Lorenzo Figini, Guglielmo Rubinacci, Peter Lang, Pierre Manas, S. Costea, A. Kirk, F. Causa, J. Adamek, Vu N. M. T., M. Cavedon, O. Grover, Geert Verdoolaege, M. Spolaore, L. Sanchis-Sanchez, P. Bohm, P. V. Kazantzidis, Sarah Newton, M. Tomes, M.-L. Mayoral, J. R. Harrison, C. Mazzotta, H. Reimerdes, Jorge Morales, D. Brunetti, J. Gonzalez-Martin, Tomas Markovic, S. S. Henderson, D. Ricci, J. Juul Rasmussen, F. Janky, S. Saarelma, Z. Popovic, C. Tsironis, J. J. Rasmussen, S. K. Hansen, Sandra C. Chapman, Volker Naulin, H. Arnichand, Roberto Paccagnella, M. Faitsch, Anders Nielsen, M. Kong, V. Igochine, C. Piron, C. Bowman, Jorge Ferreira, D. Sytnykov, K. G. McClements, Olivier Sauter, Ondrej Ficker, Matthias Wiesenberger, T. Ravensbergen, C. Reux, Irena Ivanova-Stanik, Dirk Reiser, M. Bernert, M. Vallar, J-M Moret, M. Gruca, D. I. Refy, P. Cano Megias, Benoit Labit, M. Schubert, Giuliana Sias, O. Bogar, P. J. Mc Carthy, I. Faust, Gergely Papp, F. Matos, J. Garcia, C. Marini, E. L. Sorokovoy, Dimitri Voltolina, George Wilkie, J. M. Santos, R. R. Sheeba, Vladimir Weinzettl, Sergei Kasilov, J. Cerovsky, Matteo Agostini, G. Tardini, Laurie Porte, F. Dolizy, L. Gil, Matthias Komm, A. Dal Molin, B. Sieglin, Roch Kwiatkowski, M. C. C Messmer, Toke Koldborg Jensen, Vinodh Bandaru, Ben F. McMillan, Alessandra Fanni, Daniele Carnevale, Shimpei Futatani, D. P. Coster, V. Korovin, S. E. Sharapov, Patrik Ollus, J. Gath, A. Czarnecka, D. Gallart, M. Peterka, P. Vallejos Olivares, Jernej Kovacic, Nicolas Fedorczak, Silvio Ceccuzzi, L. Piron, J. Rosato, G. Kocsis, Stefan Kragh Nielsen, M. Garcia-Mu oz, Radomir Panek, S. F. Smith, Paolo Bettini, A. Mariani, R. Dejarnac, Lorenzo Frassinetti, D. Douai, L. Garzotti, H. J. Sun, C.K. Tsui, N. den Harder, John Elmerdahl Olsen, F. Bombarda, M. Francesco, Piero Martin, D. Hogeweij, P. Blanchard, F. Bouquey, Gabor Por, Luca Boncagni, Carlo Sozzi, Martin Hron, P. A. Schneider, V. P. Loschiavo, David Terranova, D. Aguiam, D. Choi, M. Gobbin, D. Iglesias, M. Reich, G. Avdeeva, A. Gallo, O. Biletskyi, M. Aradi, F. Liu, M. Griener, Antti Snicker, L. Kripner, Jérôme Bucalossi, L. Hesslow, Nick Walkden, M. Rodriguez-Ramos, T. C. Blanken, Cristian Galperti, F. Jaulmes, G. Calabr, G.A. Rattá, W. Bin, S. Garavaglia, V. Plyusnin, Andreas Frank Martitsch, A. Zisis, Rita Lorenzini, Duccio Testa, M. Passeri, Ola Embréus, N. Krawczyk, K. Särkimäki, Davide Galassi, D. Samaddar, M. Oberkofler, E. Seliunin, D. Brida, P. Buratti, F. Nabais, J. Ongena, J. Likonen, Yann Camenen, M. J. Mantsinen, F. Carpanese, S. Wiesen, P. Piovesan, Mirko Salewski, J. Hawke, Florian Laggner, R. Bilato, M. Wischmeier, L. Pigatto, G. I. Pokol, G. Giruzzi, Jens Madsen, D. Gadariya, L. Stipani, Christian Theiler, J. Stober, Michael Barnes, Timothy Goodman, R. D. Nem, J. J. Dominguez-Palacios Duran, F. Militello, Y. Kulyk, D. J. Cruz Zabala, A. Drenik, P. Manz, M. Scheffer, V. Pericoli Radolfini, B. Tilia, John Omotani, B. Vanovac, B. S. Schneider, E. Fable, Jakub Urban, T. Gyergyek, A. N. Karpushov, M. Farnik, Jakub Seidl, Christopher G. Albert, Antoine Merle, A. Cathey, D. A. Ryan, Sergio Galeani, R. Scannell, A. Havranek, G. de Carolis, C. Soria-Hoyo, S. Gibson, D. Carralero, D. Meshcheriakov, Morten Stejner, B. P. Duval, Francesco Cordella, Mitja Kelemen, Svetlana V. Ratynskaia, Stefano Coda, L. Calacci, C. Cianfarani, Faa Federico Felici, A. C. A. Figueiredo, L. Panaccione, E. Viezzer, Fabio Villone, Daniele Milanesio, Winfried Kernbichler, Mario Sassano, A. Teplukhina, S. Zoletnik, L. Laguardia, P. Molina Cabrera, Taina Kurki-Suonio, D. Micheletti, P. Zanca, Daniel Dunai, S. Feng, J. Decker, Stylianos Varoutis, Lorella Carraro, M. Wensing, Gustavo Granucci, Artur Palha, A. Kappatou, J. Garcia-Lopez, Felix I. Parra, Ye. O. Kazakov, S. Brezinsek, Didier Mazon, A. Lahtinen, I. Paradela Perez, P. Chmielewski, L. Giacomelli, Alessandro Pau, Gianluca Spizzo, R. Delogu, R. J. Akers, H. De Oliveira, Petr Vondracek, F. P. Orsitto, J. Hobirk, L. Xiang, A. Burckhart, B. Maljaars, V. Petrzilka, Ocleto D'Arcangelo, P. David, D. Grekov, Tamás Szepesi, Y. Andr be, P. Hacek, M. Toscano-Jimenez, T. Pütterich, L. Cordaro, V. Nikolaeva, F. Orain, M. Rabinski, C. Ionita-Schrittwieser, T. Tala, Maria Ester Puiatti, A. Casolari, T. Happel, Pär Strand, Benjamin Daniel Dudson, P. Mantica, Z. Huang, D. Colette, G. Ciraolo, Jan Mlynar, W. Suttrop, C. Meineri, J. Horacek, Seppo Sipilä, M. Gospodarczyk, S. Mastrostefano, Jesús Vega, Antti Hakola, Kevin Verhaegh, Roman Schrittwieser, C. Marchetto, M. Willensdorfer, Jari Varje, D. C. van Vugt, J. Faustin, Mathias Hoppe, M. Dreval, A. Perek, C. Angioni, Laure Vermare, U. A. Sheikh, J. F. Rivero-Rodriguez, G. Rubino, S.N. Reznik, Tsv K Popov, S. Nowak, A. S. Jacobsen, J. R. Martin Solis, David Moulton, Heinz Isliker, K. Wu, Anna Salmi, F. Nespoli, S. Elmore, O. Kudlacek, A. Kallenbach, Rok Zaplotnik, D. L. Keeling, L. Giannone, M. Maraschek, Carlos B. da Silva, F. Hitzler, M. Valovic, M. W. Jakubowski, L. Gabellieri, Jozef Varju, Marco Cecconello, M. Valisa, Vlado Menkovski, Gábor Cseh, E. Thoren, T. Eich, R. Coelho, F. Bagnato, Matteo Zuin, Alexander Kendl, G. Rocchi, G. Pautasso, D. Naydenkova, R. O. Pavlichenko, M. Fontana, Lionello Marrelli, Tommaso Bolzonella, Nicola Vianello, Pascale Hennequin, R. Ochoukov, Tom Wauters, Christian Hopf, Ch. Fuchs, E. Giovannozzi, Fulvio Auriemma, Roberto Maurizio, Stefan Buller, Massimo Nocente, K. Krieger, G. Grenfell, N. Rispoli, R. Dux, Barbara Cannas, Laboratoire de Physique des Plasmas (LPP), Université Paris-Saclay-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-École polytechnique (X)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Labit, B., Eich, T., Harrer, G. F., Wolfrum, E., Bernert, M., Dunne, M. G., Frassinetti, L., Hennequin, P., Maurizio, R., Merle, A., Meyer, H., Saarelma, S., Sheikh, U., Adamek, J., Agostini, M., Aguiam, D., Akers, R., Albanese, R., Albert, C., Alessi, E., Ambrosino, R., Andr be, Y., Angioni, C., Apruzzese, G., Aradi, M., Arnichand, H., Auriemma, F., Avdeeva, G., Ayllon-Guerola, J. M., Bagnato, F., Bandaru, V. K., Barnes, M., Barrera-Orte, L., Bettini, P., Bilato, R., Biletskyi, O., Bilkova, P., Bin, W., Blanchard, P., Blanken, T., Bobkov, V., Bock, A., Boeyaert, D., Bogar, K., Bogar, O., Bohm, P., Bolzonella, T., Bombarda, F., Boncagni, L., Bouquey, F., Bowman, C., Brezinsek, S., Brida, D., Brunetti, D., Bucalossi, J., Buchanan, J., Buermans, J., Bufferand, H., Buller, S., Buratti, P., Burckhart, A., Calabr, G., Calacci, L., Camenen, Y., Cannas, B., Cano Megias, P., Carnevale, D., Carpanese, F., Carr, M., Carralero, D., Carraro, L., Casolari, A., Cathey, A., Causa, F., Cavedon, M., Cecconello, M., Ceccuzzi, S., Cerovsky, J., Chapman, S., Chmielewski, P., Choi, D., Cianfarani, C., Ciraolo, G., Coda, S., Coelho, R., Colas, L., Colette, D., Cordaro, L., Cordella, F., Costea, S., Coster, D., Cruz Zabala, D. J., Cseh, G., Czarnecka, A., Cziegler, I., D'Arcangelo, O., Dal Molin, A., David, P., De Carolis, G., De Oliveira, H., Decker, J., Dejarnac, R., Delogu, R., Den Harder, N., Dimitrova, M., Dolizy, F., Dominguez-Palacios Duran, J. J., Douai, D., Drenik, A., Dreval, M., Dudson, B., Dunai, D., Duval, B. P., Dux, R., Elmore, S., Embreus, O., Erds, B., Fable, E., Faitsch, M., Fanni, A., Farnik, M., Faust, I., Faustin, J., Fedorczak, N., Felici, F., Feng, S., Feng, X., Ferreira, J., Ferr, G., Fevrier, O., Ficker, O., Figini, L., Figueiredo, A., Fil, A., Fontana, M., Francesco, M., Fuchs, C., Futatani, S., Gabellieri, L., Gadariya, D., Gahle, D., Galassi, D., Galazka, K., Galdon-Quiroga, J., Galeani, S., Gallart, D., Gallo, A., Galperti, C., Garavaglia, S., Garcia, J., Garcia-Lopez, J., Garcia-Mu oz, M., Garzotti, L., Gath, J., Geiger, B., Giacomelli, L., Giannone, L., Gibson, S., Gil, L., Giovannozzi, E., Giruzzi, G., Gobbin, M., Gonzalez-Martin, J., Goodman, T. P., Gorini, G., Gospodarczyk, M., Granucci, G., Grekov, D., Grenfell, G., Griener, M., Groth, M., Grover, O., Gruca, M., Gude, A., Guimarais, L., Gyergyek, T., Hacek, P., Hakola, A., Ham, C., Happel, T., Harrison, J., Havranek, A., Hawke, J., Henderson, S., Hesslow, L., Hitzler, F., Hnat, B., Hobirk, J., Hoelzl, M., Hogeweij, D., Hopf, C., Hoppe, M., Horacek, J., Hron, M., Huang, Z., Iantchenko, A., Iglesias, D., Igochine, V., Innocente, P., Ionita-Schrittwieser, C., Isliker, H., Ivanova-Stanik, I., Jacobsen, A., Jakubowski, M., Janky, F., Jardin, A., Jaulmes, F., Jensen, T., Jonsson, T., Kallenbach, A., Kappatou, A., Karpushov, A., Kasilov, S., Kazakov, Y., Kazantzidis, P. V., Keeling, D., Kelemen, M., Kendl, A., Kernbichler, W., Kirk, A., Kocsis, G., Komm, M., Kong, M., Korovin, V., Koubiti, M., Kovacic, J., Krawczyk, N., Krieger, K., Kripner, L., Krivska, A., Kudlacek, O., Kulyk, Y., Kurki-Suonio, T., Kwiatkowski, R., Laggner, F., Laguardia, L., Lahtinen, A., Lang, P., Likonen, J., Lipschultz, B., Liu, F., Lombroni, R., Lorenzini, R., Loschiavo, V. P., Lunt, T., Macusova, E., Madsen, J., Maggiora, R., Maljaars, B., Manas, P., Mantica, P., Mantsinen, M. J., Manz, P., Maraschek, M., Marchenko, V., Marchetto, C., Mariani, A., Marini, C., Markovic, T., Marrelli, L., Martin, P., Martin Solis, J. R., Martitsch, A., Mastrostefano, S., Matos, F., Matthews, G., Mayoral, M. -L., Mazon, D., Mazzotta, C., Mc Carthy, P., Mcclements, K., Mcdermott, R., Mcmillan, B., Meineri, C., Menkovski, V., Meshcheriakov, D., Messmer, M., Micheletti, D., Milanesio, D., Militello, F., Miron, I. G., Mlynar, J., Moiseenko, V., Molina Cabrera, P. A., Morales, J., Moret, J. -M., Moro, A., Moulton, D., Nabais, F., Naulin, V., Naydenkova, D., Nem, R. D., Nespoli, F., Newton, S., Nielsen, A. H., Nielsen, S. K., Nikolaeva, V., Nocente, M., Nowak, S., Oberkofler, M., Ochoukov, R., Ollus, P., Olsen, J., Omotani, J., Ongena, J., Orain, F., Orsitto, F. P., Paccagnella, R., Palha, A., Panaccione, L., Panek, R., Panjan, M., Papp, G., Paradela Perez, I., Parra, F., Passeri, M., Pau, A., Pautasso, G., Pavlichenko, R., Perek, A., Pericoli Radolfini, V., Pesamosca, F., Peterka, M., Petrzilka, V., Piergotti, V., Pigatto, L., Piovesan, P., Piron, C., Piron, L., Plyusnin, V., Pokol, G., Poli, E., Poloskei, P., Popov, T., Popovic, Z., Por, G., Porte, L., Pucella, G., Puiatti, M. E., Putterich, T., Rabinski, M., Juul Rasmussen, J., Rasmussen, J., Ratta, G. A., Ratynskaia, S., Ravensbergen, T., Refy, D., Reich, M., Reimerdes, H., Reimold, F., Reiser, D., Reux, C., Reznik, S., Ricci, D., Rispoli, N., Rivero-Rodriguez, J. F., Rocchi, G., Rodriguez-Ramos, M., Romano, A., Rosato, J., Rubinacci, G., Rubino, G., Ryan, D. A., Salewski, M., Salmi, A., Samaddar, D., Sanchis-Sanchez, L., Santos, J., Sarkimaki, K., Sassano, M., Sauter, O., Scannell, R., Scheffer, M., Schneider, B. S., Schneider, P., Schrittwieser, R., Schubert, M., Seidl, J., Seliunin, E., Sharapov, S., Sheeba, R. R., Sias, G., Sieglin, B., Silva, C., Sipila, S., Smith, S., Snicker, A., Solano, E. R., Hansen, S. K., Soria-Hoyo, C., Sorokovoy, E., Sozzi, C., Sperduti, A., Spizzo, G., Spolaore, M., Stejner, M., Stipani, L., Stober, J., Strand, P., Sun, H., Suttrop, W., Sytnykov, D., Szepesi, T., Tal, B., Tala, T., Tardini, G., Tardocchi, M., Teplukhina, A., Terranova, D., Testa, D., Theiler, C., Thoren, E., Thornton, A., Tilia, B., Tolias, P., Tomes, M., Toscano-Jimenez, M., Tsironis, C., Tsui, C., Tudisco, O., Urban, J., Valisa, M., Vallar, M., Vallejos Olivares, P., Valovic, M., Van Vugt, D., Vanovac, B., Varje, J., Varju, J., Varoutis, S., Vartanian, S., Vasilovici, O., Vega, J., Verdoolaege, G., Verhaegh, K., Vermare, L., Vianello, N., Vicente, J., Viezzer, E., Villone, F., Voitsekhovitch, I., Voltolina, D., Vondracek, P., Vu, N. M. T., Walkden, N., Wauters, T., Weiland, M., Weinzettl, V., Wensing, M., Wiesen, S., Wiesenberger, M., Wilkie, G., Willensdorfer, M., Wischmeier, M., Wu, K., Xiang, L., Zagorski, R., Zaloga, D., Zanca, P., Zaplotnik, R., Zebrowski, J., Zhang, W., Zisis, A., Zoletnik, S., Zuin, M., Swiss Federal Institute of Technology Lausanne, Max-Planck-Institut für Plasmaphysik, Vienna University of Technology, KTH Royal Institute of Technology, Université Paris-Saclay, JET, Czech Academy of Sciences, National Research Council of Italy, University of Lisbon, University of Naples Federico II, Graz University of Technology, University of Naples Parthenope, Agenzia nazionale per le nuove tecnologie, l'energia e lo sviluppo economico sostenibile, Danmarks Tekniske Universitet, University of Seville, University of Oxford, EUROfusion Programme Management Unit, National Science Center Kharkov Institute of Physics and Technology, Eindhoven University of Technology, Forschungszentrum Jülich, CEA, University of York, Royal Military Academy, Chalmers University of Technology, Tuscia University, Università di Roma Tor Vergata, CNRS, University of Cagliari, CIEMAT, Uppsala University, University of Warwick, Soltan Institute for Nuclear Studies, University of Innsbruck, Hungarian Academy of Sciences, Budapest University of Technology and Economics, Durham University, BarcelonaTech, University of Strathclyde, Barcelona Supercomputing Center, University of Milan - Bicocca, Karlsruhe Institute of Technology, Fusion and Plasma Physics, J. Stefan Institute, VTT Technical Research Centre of Finland, Dutch Institute for Fundamental Energy Research, Aristotle University of Thessaloniki, National Technical University of Athens, National Centre for Nuclear Research, University of Helsinki, Université Côte d'Azur, Polytechnic University of Turin, NASU - Institute of Nuclear Research, University of Cassino and Southern Lazio, University College Cork, National Institute for Laser, Plasma and Radiation Physics, Department of Applied Physics, Sofia University St. Kliment Ohridski, Ghent University, Aalto-yliopisto, Aalto University, Labit, B, Eich, T, Harrer, G, Wolfrum, E, Bernert, M, Dunne, M, Frassinetti, L, Hennequin, P, Maurizio, R, Merle, A, Meyer, H, Saarelma, S, Sheikh, U, Adamek, J, Agostini, M, Aguiam, D, Akers, R, Albanese, R, Albert, C, Alessi, E, Ambrosino, R, Andr be, Y, Angioni, C, Apruzzese, G, Aradi, M, Arnichand, H, Auriemma, F, Avdeeva, G, Ayllon-Guerola, J, Bagnato, F, Bandaru, V, Barnes, M, Barrera-Orte, L, Bettini, P, Bilato, R, Biletskyi, O, Bilkova, P, Bin, W, Blanchard, P, Blanken, T, Bobkov, V, Bock, A, Boeyaert, D, Bogar, K, Bogar, O, Bohm, P, Bolzonella, T, Bombarda, F, Boncagni, L, Bouquey, F, Bowman, C, Brezinsek, S, Brida, D, Brunetti, D, Bucalossi, J, Buchanan, J, Buermans, J, Bufferand, H, Buller, S, Buratti, P, Burckhart, A, Calabr, G, Calacci, L, Camenen, Y, Cannas, B, Cano Megias, P, Carnevale, D, Carpanese, F, Carr, M, Carralero, D, Carraro, L, Casolari, A, Cathey, A, Causa, F, Cavedon, M, Cecconello, M, Ceccuzzi, S, Cerovsky, J, Chapman, S, Chmielewski, P, Choi, D, Cianfarani, C, Ciraolo, G, Coda, S, Coelho, R, Colas, L, Colette, D, Cordaro, L, Cordella, F, Costea, S, Coster, D, Cruz Zabala, D, Cseh, G, Czarnecka, A, Cziegler, I, D'Arcangelo, O, Dal Molin, A, David, P, De Carolis, G, De Oliveira, H, Decker, J, Dejarnac, R, Delogu, R, Den Harder, N, Dimitrova, M, Dolizy, F, Dominguez-Palacios Duran, J, Douai, D, Drenik, A, Dreval, M, Dudson, B, Dunai, D, Duval, B, Dux, R, Elmore, S, Embreus, O, Erds, B, Fable, E, Faitsch, M, Fanni, A, Farnik, M, Faust, I, Faustin, J, Fedorczak, N, Felici, F, Feng, S, Feng, X, Ferreira, J, Ferr, G, Fevrier, O, Ficker, O, Figini, L, Figueiredo, A, Fil, A, Fontana, M, Francesco, M, Fuchs, C, Futatani, S, Gabellieri, L, Gadariya, D, Gahle, D, Galassi, D, Galazka, K, Galdon-Quiroga, J, Galeani, S, Gallart, D, Gallo, A, Galperti, C, Garavaglia, S, Garcia, J, Garcia-Lopez, J, Garcia-Mu oz, M, Garzotti, L, Gath, J, Geiger, B, Giacomelli, L, Giannone, L, Gibson, S, Gil, L, Giovannozzi, E, Giruzzi, G, Gobbin, M, Gonzalez-Martin, J, Goodman, T, Gorini, G, Gospodarczyk, M, Granucci, G, Grekov, D, Grenfell, G, Griener, M, Groth, M, Grover, O, Gruca, M, Gude, A, Guimarais, L, Gyergyek, T, Hacek, P, Hakola, A, Ham, C, Happel, T, Harrison, J, Havranek, A, Hawke, J, Henderson, S, Hesslow, L, Hitzler, F, Hnat, B, Hobirk, J, Hoelzl, M, Hogeweij, D, Hopf, C, Hoppe, M, Horacek, J, Hron, M, Huang, Z, Iantchenko, A, Iglesias, D, Igochine, V, Innocente, P, Ionita-Schrittwieser, C, Isliker, H, Ivanova-Stanik, I, Jacobsen, A, Jakubowski, M, Janky, F, Jardin, A, Jaulmes, F, Jensen, T, Jonsson, T, Kallenbach, A, Kappatou, A, Karpushov, A, Kasilov, S, Kazakov, Y, Kazantzidis, P, Keeling, D, Kelemen, M, Kendl, A, Kernbichler, W, Kirk, A, Kocsis, G, Komm, M, Kong, M, Korovin, V, Koubiti, M, Kovacic, J, Krawczyk, N, Krieger, K, Kripner, L, Krivska, A, Kudlacek, O, Kulyk, Y, Kurki-Suonio, T, Kwiatkowski, R, Laggner, F, Laguardia, L, Lahtinen, A, Lang, P, Likonen, J, Lipschultz, B, Liu, F, Lombroni, R, Lorenzini, R, Loschiavo, V, Lunt, T, Macusova, E, Madsen, J, Maggiora, R, Maljaars, B, Manas, P, Mantica, P, Mantsinen, M, Manz, P, Maraschek, M, Marchenko, V, Marchetto, C, Mariani, A, Marini, C, Markovic, T, Marrelli, L, Martin, P, Martin Solis, J, Martitsch, A, Mastrostefano, S, Matos, F, Matthews, G, Mayoral, M, Mazon, D, Mazzotta, C, Mc Carthy, P, Mcclements, K, Mcdermott, R, Mcmillan, B, Meineri, C, Menkovski, V, Meshcheriakov, D, Messmer, M, Micheletti, D, Milanesio, D, Militello, F, Miron, I, Mlynar, J, Moiseenko, V, Molina Cabrera, P, Morales, J, Moret, J, Moro, A, Moulton, D, Nabais, F, Naulin, V, Naydenkova, D, Nem, R, Nespoli, F, Newton, S, Nielsen, A, Nielsen, S, Nikolaeva, V, Nocente, M, Nowak, S, Oberkofler, M, Ochoukov, R, Ollus, P, Olsen, J, Omotani, J, Ongena, J, Orain, F, Orsitto, F, Paccagnella, R, Palha, A, Panaccione, L, Panek, R, Panjan, M, Papp, G, Paradela Perez, I, Parra, F, Passeri, M, Pau, A, Pautasso, G, Pavlichenko, R, Perek, A, Pericoli Radolfini, V, Pesamosca, F, Peterka, M, Petrzilka, V, Piergotti, V, Pigatto, L, Piovesan, P, Piron, C, Piron, L, Plyusnin, V, Pokol, G, Poli, E, Poloskei, P, Popov, T, Popovic, Z, Por, G, Porte, L, Pucella, G, Puiatti, M, Putterich, T, Rabinski, M, Juul Rasmussen, J, Rasmussen, J, Ratta, G, Ratynskaia, S, Ravensbergen, T, Refy, D, Reich, M, Reimerdes, H, Reimold, F, Reiser, D, Reux, C, Reznik, S, Ricci, D, Rispoli, N, Rivero-Rodriguez, J, Rocchi, G, Rodriguez-Ramos, M, Romano, A, Rosato, J, Rubinacci, G, Rubino, G, Ryan, D, Salewski, M, Salmi, A, Samaddar, D, Sanchis-Sanchez, L, Santos, J, Sarkimaki, K, Sassano, M, Sauter, O, Scannell, R, Scheffer, M, Schneider, B, Schneider, P, Schrittwieser, R, Schubert, M, Seidl, J, Seliunin, E, Sharapov, S, Sheeba, R, Sias, G, Sieglin, B, Silva, C, Sipila, S, Smith, S, Snicker, A, Solano, E, Hansen, S, Soria-Hoyo, C, Sorokovoy, E, Sozzi, C, Sperduti, A, Spizzo, G, Spolaore, M, Stejner, M, Stipani, L, Stober, J, Strand, P, Sun, H, Suttrop, W, Sytnykov, D, Szepesi, T, Tal, B, Tala, T, Tardini, G, Tardocchi, M, Teplukhina, A, Terranova, D, Testa, D, Theiler, C, Thoren, E, Thornton, A, Tilia, B, Tolias, P, Tomes, M, Toscano-Jimenez, M, Tsironis, C, Tsui, C, Tudisco, O, Urban, J, Valisa, M, Vallar, M, Vallejos Olivares, P, Valovic, M, Van Vugt, D, Vanovac, B, Varje, J, Varju, J, Varoutis, S, Vartanian, S, Vasilovici, O, Vega, J, Verdoolaege, G, Verhaegh, K, Vermare, L, Vianello, N, Vicente, J, Viezzer, E, Villone, F, Voitsekhovitch, I, Voltolina, D, Vondracek, P, Vu, N, Walkden, N, Wauters, T, Weiland, M, Weinzettl, V, Wensing, M, Wiesen, S, Wiesenberger, M, Wilkie, G, Willensdorfer, M, Wischmeier, M, Wu, K, Xiang, L, Zagorski, R, Zaloga, D, Zanca, P, Zaplotnik, R, Zebrowski, J, Zhang, W, Zisis, A, Zoletnik, S, Zuin, M, Universitat Politècnica de Catalunya. Departament de Física, Universitat Politècnica de Catalunya. ANT - Advanced Nuclear Technologies Research Group, Control Systems Technology, Science and Technology of Nuclear Fusion, Data Mining, Sensorics for fusion reactors, and Magneto-Hydro-Dynamic Stability of Fusion Plasmas

Subjects
Nuclear and High Energy Physics, Settore ING-INF/04, Work package, grassy ELM, ballooning modes, Nuclear physics, 01 natural sciences, Flattening, Ballooning, 010305 fluids & plasmas, grassy ELMs, separatrix density, ASDEX Upgrade, [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], 0103 physical sciences, 010306 general physics, Edge-localized mode, QC, H-mode, plasma triangularity, type-II ELMs, Physics, Física [Àrees temàtiques de la UPC], type-II ELM, Plasma, Condensed Matter Physics, Null (physics), Shear (sheet metal), Física nuclear, Atomic physics, ballooning mode
Abstract

Within the EUROfusion MST1 work package, a series of experiments has been conducted on AUG and TCV devices to disentangle the role of plasma fueling and plasma shape for the onset of small ELM regimes. On both devices, small ELM regimes with high confinement are achieved if and only if two conditions are fulfilled at the same time. Firstly, the plasma density at the separatrix must be large enough (), leading to a pressure profile flattening at the separatrix, which stabilizes type-I ELMs. Secondly, the magnetic configuration has to be close to a double null (DN), leading to a reduction of the magnetic shear in the extreme vicinity of the separatrix. As a consequence, its stabilizing effect on ballooning modes is weakened. Peer Reviewed Article escrit per 365 autors/autores: Labit, B.; Eich, T.; Harrer, G. F.; Wolfrum, E.; Bernert, M.; Dunne, M. G.; Frassinetti, L.; Hennequin, P.; Maurizio, R.; Merle, A.; Meyer, H.; Saarelma, S.; Sheikh, U.; Adamek, J.; Agostini, M.; Aguiam, D.; Akers, R.; Albanese, R.; Albert, C.; Alessi, E.; Ambrosino, R.; Andr be, Y.; Angioni, C.; Apruzzese, G.; Aradi, M.; Arnichand, H.; Auriemma, F.; Avdeeva, G.; Ayllon-Guerola, J. M.; Bagnato, F.; Bandaru, V. K.; Barnes, M.; Barrera-Orte, L.; Bettini, P.; Bilato, R.; Biletskyi, O.; Bilkova, P.; Bin, W.; Blanchard, P.; Blanken, T.; Bobkov, V.; Bock, A.; Boeyaert, D.; Bogar, K.; Bogar, O.; Bohm, P.; Bolzonella, T.; Bombarda, F.; Boncagni, L.; Bouquey, F.; Bowman, C.; Brezinsek, S.; Brida, D.; Brunetti, D.; Bucalossi, J.; Buchanan, J.; Buermans, J.; Bufferand, H.; Buller, S.; Buratti, P.; Burckhart, A.; Calabr, G.; Calacci, L.; Camenen, Y.; Cannas, B.; Cano Megías, P.; Carnevale, D.; Carpanese, F.; Carr, M.; Carralero, D.; Carraro, L.; Casolari, A.; Cathey, A.; Causa, F.; Cavedon, M.; Cecconello, M.; Ceccuzzi, S.; Cerovsky, J.; Chapman, S.; Chmielewski, P.; Choi, D.; Cianfarani, C.; Ciraolo, G.; Coda, S.; Coelho, R.; Colas, L.; Colette, D.; Cordaro, L.; Cordella, F.; Costea, S.; Coster, D.; Cruz Zabala, D. J.; Cseh, G.; Czarnecka, A.; Cziegler, I.; D’Arcangelo, O.; Dal Molin, A.; David, P.; De Carolis, G.; De Oliveira, H.; Decker, J.; Dejarnac, R.; Delogu, R.; Den Harder, N.; Dimitrova, M.; Dolizy, F.; Domínguez-Palacios Durán, J. J.; Douai, D.; Drenik, A.; Dreval, M.; Dudson, B.; Dunai, D.; Duval, B. P.; Dux, R.; Elmore, S.; Embréus, O.; Erds, B.; Fable, E.; Faitsch, M.; Fanni, A.; Farnik, M.; Faust, I.; Faustin, J.; Fedorczak, N.; Felici, F.; Feng, S.; Feng, X.; Ferreira, J.; Ferr, G.; Février, O.; Ficker, O.; Figini, L.; Figueiredo, A.; Fil, A.; Fontana, M.; Francesco, M.; Fuchs, C.; Futatani, S.; Gabellieri, L.; Gadariya, D.; Gahle, D.; Galassi, D.; Gałązka, K.; Galdon-Quiroga, J.; Galeani, S.; Gallart, D.; Gallo, A.; Galperti, C.; Garavaglia, S.; Garcia, J.; Garcia-Lopez, J.; Garcia-Mu oz, M.; Garzotti, L.; Gath, J.; Geiger, B.; Giacomelli, L.; Giannone, L.; Gibson, S.; Gil, L.; Giovannozzi, E.; Giruzzi, G.; Gobbin, M.; Gonzalez-Martin, J.; Goodman, T. P.; Gorini, G.; Gospodarczyk, M.; Granucci, G.; Grekov, D. 1; Grenfell, G.; Griener, M.; Groth, M.; Grover, O.; Gruca, M.; Gude, A.; Guimarais, L.; Gyergyek, T.; Hacek, P.; Hakola, A.; Ham, C.; Happel, T.; Harrison, J.; Havranek, A.; Hawke, J.; Henderson, S.; Hesslow, L.; Hitzler, F.; Hnat, B.; Hobirk, J.; Hoelzl, M.; Hogeweij, D.; Hopf, C.; Hoppe, M.; Horacek, J.; Hron, M.; Huang, Z.; Iantchenko, A.; Iglesias, D.; Igochine, V.; Innocente, P.; Ionita-Schrittwieser, C.; Isliker, H.; Ivanova-Stanik, I.; Jacobsen, A.; Jakubowski, M.; Janky, F.; Jardin, A.; Jaulmes, F.; Jensen, T.; Jonsson, T.; Kallenbach, A.; Kappatou, A.; Karpushov, A.; Kasilov, S.; Kazakov, Y.; Kazantzidis, P. V.; Keeling, D.; Kelemen, M.; Kendl, A.; Kernbichler, W.; Kirk, A.; Kocsis, G.; Komm, M.; Kong, M.; Korovin, V.; Koubiti, M.; Kovacic, J.; Krawczyk, N.; Krieger, K.; Kripner, L.; Křivská, A.; Kudlacek, O.; Kulyk, Y.; Kurki-Suonio, T.; Kwiatkowski, R.; Laggner, F.; Laguardia, L.; Lahtinen, A.; Lang, P.; Likonen, J.; Lipschultz, B.; Liu, F.; Lombroni, R.; Lorenzini, R.; Loschiavo, V. P.; Lunt, T.; MacUsova, E.; Madsen, J.; Maggiora, R.; Maljaars, B.; Manas, P.; Mantica, P.; Mantsinen, M. J.; Manz, P.; Maraschek, M.; Marchenko, V.; Marchetto, C.; Mariani, A.; Marini, C.; Markovic, T.; Marrelli, L.; Martin, P.; Martín Solís, J. R.; Martitsch, A.; Mastrostefano, S.; Matos, F.; Matthews, G.; Mayoral, M.-L.; Mazon, D.; Mazzotta, C.; Mc Carthy, P.; McClements, K.; McDermott, R.; McMillan, B.; Meineri, C.; Menkovski, V.; Meshcheriakov, D.; Messmer, M.; Micheletti, D.; Milanesio, D.; Militello, F.; Miron, I. G.; Mlynar, J.; Moiseenko, V.; Molina Cabrera, P. A.; Morales, J.; Moret, J.-M.; Moro, A.; Moulton, D.; Nabais, F.; Naulin, V.; Naydenkova, D.; Nem, R. D.; Nespoli, F.; Newton, S.; Nielsen, A. H.; Nielsen, S. K.; Nikolaeva, V.; Nocente, M.; Nowak, S.; Oberkofler, M.; Ochoukov, R.; Ollus, P.; Olsen, J.; Omotani, J.; Ongena, J.; Orain, F.; Orsitto, F. P.; Paccagnella, R.; Palha, A.; Panaccione, L.; Panek, R.; Panjan, M.; Papp, G.; Paradela Perez, I.; Parra, F.; Passeri, M.; Pau, A.; Pautasso, G.; Pavlichenko, R.; Perek, A.; Pericoli Radolfini, V.; Pesamosca, F.; Peterka, M.; Petrzilka, V.; Piergotti, V.; Pigatto, L.; Piovesan, P.; Piron, C.; Piron, L.; Plyusnin, V.; Pokol, G.; Poli, E.; Pölöskei, P.; Popov, T.; Popovic, Z.; Pór, G.; Porte, L.; Pucella, G.; Puiatti, M. E.; Pütterich, T.; Rabinski, M.; Juul Rasmussen, J.; Rasmussen, J.; Rattá, G. A.; Ratynskaia, S.; Ravensbergen, T.; Réfy, D.; Reich, M.; Reimerdes, H.; Reimold, F.; Reiser, D.; Reux, C.; Reznik, S.; Ricci, D.; Rispoli, N.; Rivero-Rodriguez, J. F.; Rocchi, G.; Rodriguez-Ramos, M.; Romano, A.; Rosato, J.; Rubinacci, G.; Rubino, G.; Ryan, D. A.; Salewski, M.; Salmi, A.; Samaddar, D.; Sanchis-Sanchez, L.; Santos, J.; Särkimäki, K.; Sassano, M.; Sauter, O.; Scannell, R.; Scheffer, M.; Schneider, B. S.; Schneider, P.; Schrittwieser, R.; Schubert, M.; Seidl, J.; Seliunin, E.; Sharapov, S.; Sheeba, R. R.; Sias, G.; Sieglin, B.; Silva, C.; Sipilä, S.; Smith, S.; Snicker, A.; Solano, E. R.; Hansen, S. K.; Soria-Hoyo, C.; Sorokovoy, E.; Sozzi, C.; Sperduti, A.; Spizzo, G.; Spolaore, M.; Stejner, M.; Stipani, L.; Stober, J.; Strand, P.; Sun, H.; Suttrop, W.; Sytnykov, D.; Szepesi, T.; Tál, B.; Tala, T.; Tardini, G.; Tardocchi, M.; Teplukhina, A.; Terranova, D.; Testa, D.; Theiler, C.; Thorén, E.; Thornton, A.; Tilia, B.; Tolias, P.; Tomes, M.; Toscano-Jimenez, M.; Tsironis, C.; Tsui, C.; Tudisco, O.; Urban, J.; Valisa, M.; Vallar, M.; Vallejos Olivares, P.; Valovic, M.; Van Vugt, D.; Vanovac, B.; Varje, J.; Varju, J.; Varoutis, S. 1; Vartanian, S.; Vasilovici, O.; Vega, J.; Verdoolaege, G.; Verhaegh, K.; Vermare, L.; Vianello, N.; Vicente, J.; Viezzer, E.; Villone, F.; Voitsekhovitch, I.; Voltolina, D.; Vondracek, P.; Vu, N. M. T.; Walkden, N.; Wauters, T.; Weiland, M.; Weinzettl, V.; Wensing, M.; Wiesen, S.; Wiesenberger, M.; Wilkie, G.; Willensdorfer, M.; Wischmeier, M.; Wu, K.; Xiang, L.; Zagorski, R.; Zaloga, D.; Zanca, P.; Zaplotnik, R.; Zebrowski, J.; Zhang, W.; Zisis, A.; Zoletnik, S.; Zuin, M.

Published
2019

27. In-situ real-time monitoring of spurious modes in HE11 transmission lines using multi-hole couplers in miter bends

Author

Carsten Lechte, W. Kasparek, A. Zach, H. Schütz, Thomas Hirth, B. Plaum, J. Stober, F. Monaco, and Hiroshi Idei

Subjects
Coupling, Physics, business.industry, QC1-999, Physics::Optics, Signal, law.invention, Miter joint, Electric power transmission, Optics, Transmission (telecommunications), law, Transmission line, Gyrotron, ddc:000, business, Computer science, information & general works, Waveguide
Abstract

Transmission of high-power millimeter waves for ECRH is often realised with oversized corrugated circular waveguides. Coupling from the gyrotron source to the waveguide is typically done via matching mirrors in free space. Small alignment errors of the system lead to the excitation of higher-order modes inside the waveguide beside the main transmission mode HE11. Those modes have comparably higher losses and can in worst case result in local fields exceeding the breakdown limit of the medium inside the waveguide. For alignment control over the whole pulse duration of the gyrotron, a set of hole-array couplers placed into a miter bend mirror probes the field inside the waveguide. The arrays are designed to detect the marker modes for beam offset and tilt (LP(e=o)11 )as well as for beam waist mismatch (LP02). In addition, a main mode coupler sensitive mostly for the HE11 content is used as a power monitor. By maximizing the signal of the power monitor and minimizing the content of marker modes, a first-order optimization of the coupling from free space to the waveguide can be achieved. Signal processing of the 140 GHz information is done at kHz range after downmixing, using a frequency shifted part of the power monitor signal. As the measurement system is placed in a miter bend mirror, it can also be easily installed at various locations along the transmission line to check for possible misalignments of the waveguide connections between miter bends. Simulation and low power experimental results will be shown.

Published
2019

28. Parametric decay instabilities near the second-harmonic upper hybrid resonance in fusion plasmas

Author

J. Juul Rasmussen, Toke Koldborg Jensen, Matthias Hoelzl, J. Stober, Morten Stejner, Stefan Kragh Nielsen, S.K. Hansen, and ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society

Subjects
Upper hybrid waves, Physics, Nuclear and High Energy Physics, ELMs, Wave trapping, Fusion plasma, Parametric decay instability, Resonance, Condensed Matter Physics, 7. Clean energy, 01 natural sciences, Blobs, ECRH, 010305 fluids & plasmas, Physics::Plasma Physics, 0103 physical sciences, Harmonic, Microwave diagnostics, Atomic physics, 010306 general physics, Parametric statistics
Abstract

Parametric decay instabilities (PDIs) lead to the generation of strong frequency-shifted radiation when powerful X-mode polarized microwaves, injected for electron cyclotron resonance heating (ECRH) of fusion plasmas, cross a region of non-monotonic electron density near the second-harmonic upper hybrid resonance (UHR). For the standard second-harmonic X-mode ECRH scenarios used at the ASDEX Upgrade tokamak, the second-harmonic UHR occurs near the plasma edge, meaning that PDIs occur in connection with phenomena leading to non-monotonic edge electron density profiles, e.g. blobs, edge-localized modes (ELMs), and inter-ELM modes. We present the first study of strong signals near half the ECRH frequency in fusion-relevant plasmas and demonstrate their PDI-like features, such as an ECRH power threshold required for their occurrence, through analog modulations of the ECRH power. The signals near half the ECRH frequency are found to be far more prevalent than expected based on previous theories, and we hence present a qualitative explanation of their origin, in terms of cross-polarized microwaves generated through non-linear interactions of the waves involved in the PDIs, which captures the basic features of the experimental observations. We additionally present examples of the PDI-related microwave signals just below the ECRH frequency which indicate the location of the microwave source. Furthermore, based on a non-linear magnetohydrodynamics simulation of an ELM crash in ASDEX Upgrade, performed using the JOREK code, the duration of the PDI-like microwave spikes observed in connection with ELMs is shown to match the transit time of an ELM filament though an ECRH beam. Finally, the PDI power threshold expected theoretically, calculated using the electron density and temperature profiles from the JOREK simulation, is shown to match the experimentally observed values.

Published
2020

29. Generation and dissipation of runaway electrons in ASDEX Upgrade experiments

Author

O. Linder, A. Gude, J. Stober, R. Dux, M. Bernert, Michael Lehnen, Gergely Papp, M. G. Dunne, G. Pautasso, M. Dibon, E. Fable, Peter Lang, A. Mlynek, Patrick J. McCarthy, ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society, and EUROfusion MST1 Team

Subjects
Physics, Nuclear and High Energy Physics, Millisecond, Argon, chemistry.chemical_element, Plasma, Dissipation, Condensed Matter Physics, 01 natural sciences, 010305 fluids & plasmas, Computational physics, ASDEX Upgrade, chemistry, 0103 physical sciences, Coulomb, Current (fluid), 010306 general physics, Beam (structure)
Abstract

The paper describes under which plasma and machine conditions runaway electrons (REs) are generated during ASDEX Upgrade plasma disruptions. The REs are created by argon injection to investigate methods of current and energy dissipation. The RE beams are stable and last up to a few hundred milliseconds. The experimental findings are described and made available for the validation of theoretical models. In the following, a simple 0D fluid model is used to simulate the observed RE current magnitude and time behavior. In spite of its simplicity, the model is consistent with the measured RE current. The injection of heavy gases into the RE beam is then discussed in some detail: The injected gas penetrates into the low density background plasma and through the beam without ionizing significantly. Therefore its effect on the REs can be tested directly and it is found to be consistent with the known Coulomb collisional theory.

Published
2020

30. The Multi-Frequency ECRH System at ASDEX Upgrade - Current Status and Plans

Author

M. Kircher, M. Schubert, M. Thumm, A. Zach, F. Leuterer, Burkhard Plaum, E. M. Tai, G. Gantenbein, Aleksandr Grigorievich Litvak, A. V. Chirkov, V. I. Malygin, Andreas Meier, V. O. Nichiporenko, M. Münich, F. Monaco, T.A. Scherer, E. A. Solyanova, L. G. Popov, Dirk Strauss, C. Lechte, V. E. Myasnikov, G. G. Denisov, John Jelonnek, W. Kasparek, J. Stober, H. Zohm, D. Wagner, and ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society

Subjects
010302 applied physics, business.industry, Terahertz radiation, Computer science, Electrical engineering, Stray radiation, 01 natural sciences, Optical switch, 010309 optics, Electric power transmission, Upgrade, ASDEX Upgrade, 0103 physical sciences, Power dividers and directional couplers, Current (fluid), business
Abstract

Last year, two more two-frequency 1 MW gyrotrons have been installed and put into operation at ASDEX Upgrade. In total 6 gyrotrons were in operation in the last experimental campaign. This year, two more gyrotrons will be installed which will bring the upgraded ECRH system to its completion. The system upgrade also includes technological advances in subsystems and loads as well as new concepts for passive protection of in-vessel components against ECRH stray radiation.

Published
2018

31. Feedback controlled, reactor relevant, high-density, high-confinement scenarios at ASDEX Upgrade

Author

Peter Lang, O. J. W. F. Kardaun, Faa Federico Felici, T. C. Blanken, A. Kallenbach, E. Wolfrum, V. Mertens, R. Fischer, F. Janky, R. M. McDermott, O. Kudlacek, A. Mlynek, Bernhard Ploeckl, J. Stober, H. Zohm, M. G. Dunne, W. Treutterer, V. Bobkov, Control Systems Technology, and ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society

Subjects
Nuclear and High Energy Physics, Tokamak, Materials science, Nuclear engineering, Divertor, Pellets, Plasma, Condensed Matter Physics, 01 natural sciences, 010305 fluids & plasmas, law.invention, Coping (joinery), feedback control, all metal wall, ASDEX Upgrade, law, Control system, fuelling, pellet, 0103 physical sciences, Seeding, 010306 general physics, tokamak
Abstract

One main programme topic at the ASDEX Upgrade all-metal-wall tokamak is development of a high-density regime with central densities at reactor grade level while retaining high-confinement properties. This required development of appropriate control techniques capable of coping with the pellet tool, a powerful means of fuelling but one which presented challenges to the control system for handling of related perturbations. Real-time density profile control was demonstrated, raising the core density well above the Greenwald density while retaining the edge density in order to avoid confinement losses. Recently, a new model-based approach was implemented that allows direct control of the central density. Investigations focussed first on the N-seeding scenario owing to its proven potential to yield confinement enhancements. Combining pellets and N seeding was found to improve the divertor buffering further and enhance the operational range accessible. For core densities up to about the Greenwald density, a clear improvement with respect to the non-seeding reference was achieved; however, at higher densities this benefit is reduced. This behaviour is attributed to recurrence of an outward shift of the edge density profile, resulting in a reduced peeling-ballooning stability. This is similar to the shift seen during strong gas puffing, which is required to prevent impurity influx in ASDEX Upgrade. First tests indicate that highly-shaped plasma configurations like the ITER base-line scenario, respond very well to pellet injection, showing efficient fuelling with no measurable impact on the edge density profile.

Published
2018

32. Synthesis of reflection gratings for advanced plasma heating scenarios

Author

A. Zeitler, Burkhard Plaum, W. Kasparek, Carsten Lechte, J. Stober, M. Schubert, and ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society

Subjects
010302 applied physics, Materials science, Optics, Plasma heating, business.industry, Physics, QC1-999, 0103 physical sciences, Reflection (physics), business, 01 natural sciences, 010305 fluids & plasmas
Published
2018

33. Analysis of electron cyclotron emission with extended electron cyclotron forward modeling

Author

E. Westerhof, Emanuele Poli, Omar Maj, S. S. Denk, R. Fischer, W. Suttrop, H. M. Smith, Per Helander, Ulrich Stroth, M. Willensdorfer, J. Stober, and ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society

Subjects
Physics, Nuclear Energy and Engineering, law, 0103 physical sciences, Cyclotron, Electron, Atomic physics, 010306 general physics, Condensed Matter Physics, 01 natural sciences, 010305 fluids & plasmas, law.invention, ddc
Published
2018

34. OVERVIEW OF PHYSICS STUDIES ON ASDEX UPGRADE

Author

Neville C. Luhmann, J. Mailloux, A. Kappatou, Yann Camenen, R. Arredondo Parra, P. Petersson, G. F. Harrer, I. Gomez Ortiz, E. Giovannozzi, S. S. Henderson, C. Sommariva, Thomas Schwarz-Selinger, G. Fuchert, Christopher G. Albert, P. Piovesan, A. Herrmann, C. Piron, Robert Lunsford, J. Hobirk, F. Clairet, L. Xiang, Carlo Cazzaniga, A. Burckhart, B. Kurzan, Bernhard Ploeckl, G. Kocsis, A. Mancini, Benoit Labit, M. Reich, N. den Harder, Faa Federico Felici, M. Oberparleiter, Tamás Szepesi, Sibylle Günter, K. Behler, R. Merkel, Ocleto D'Arcangelo, G. Haas, Alessandro Bortolon, T. B. Cote, E. Trier, P. Simon, A. Gude, Daniele Milanesio, Winfried Kernbichler, Dorothea Gradic, M. Rodriguez-Ramos, G.A. Rattá, G. Croci, O. Tudisco, E. Heyn, M. Groth, J. Gonzalez Martin, Olivier Sauter, Irena Ivanova-Stanik, Massimo Nocente, J. R. Harrison, Martin Heyn, C. Bruhn, C. Ham, L. Shao, M. Schubert, F. Brochard, Yu Gao, Bernd Heinemann, Sandra C. Chapman, Armin Manhard, S. S. Denk, A. Jardin, D. P. Coster, G. Schall, L. Horvath, Alexander Creely, Roman Schrittwieser, Patrick J. McCarthy, C. Castaldo, B. Wiringer, M. J. Mantsinen, Till Höschen, Ph. Lauber, V. Mertens, Anders Nielsen, G. Suarez, M. E. Manso, M. Dibon, S. Wiesen, Mirko Salewski, C. D. Challis, J. Schweinzer, D. Douai, Lorenzo Frassinetti, R. C. Wolf, Mirko Ramisch, P. de Marne, Yueqiang Liu, H. van den Brand, S. Nowak, E. Joffrin, M. Teschke, Karl Schmid, D. Silvagni, L. Giannone, D. I. Refy, E. Wolfrum, M. Sertoli, Chanho Moon, O. J. W. F. Kardaun, A. Ross, S. Elgeti, A. Shalpegin, G. D. Conway, A. Sigalov, Alberto Bottino, Benedikt Geiger, M. Willensdorfer, D. C. van Vugt, Mark Maraschek, W. Zhang, M. Oberkofler, M. Griener, Stylianos Varoutis, Bill Scott, F. Monaco, W. Suttrop, Helmut Faugel, Christian Hopf, J. Vicente, Gerhard Raupp, S. Fietz, Omar Maj, D. Terranova, Q. Yu, E. Seliunin, L. Gil, K. Lackner, I. Novikau, S. Heinzel, G. Birkenmeier, O. Linder, I. Zammuto, H. Fünfgelder, Alessandro Biancalani, D. Prisiazhniuk, Analiza M. Silva, Volker Hauer, Ulrich Stroth, M. Faitsch, Toke Koldborg Jensen, S. Brezinsek, S. Garavaglia, V. Nikolaeva, C. Angioni, T. Maceina, Antti Snicker, O. Schmitz, T. Vierle, A. Scarabosio, D. Carlton, F. Penzel, M. Tardocchi, Riccardo Maggiora, V. Plyusnin, A. Bergmann, A. Bock, G. Rocchi, Andreas Frank Martitsch, J. W. Coenen, I. Erofeev, Pierre Manas, J. Stober, O. Meyer, M. A. Van Zeeland, A. S. Jacobsen, H. Meister, Jens Madsen, E. Smigelskis, A. Lohs, T. Happel, A. Gallo, F. Ryter, P. A. Schneider, A. Kallenbach, Alf Köhn, C. Bottereau, I. Paradela Perez, N. Arden, M. Koubiti, Gergely Papp, Burkhard Plaum, Jorge Ferreira, P. Denner, H. Greuner, Daniel Told, M. Weiland, T. Hayward-Schneider, B. Sieglin, A. Buhler, B. Böswirth, A. Krämer-Flecken, F. Jaulmes, J. Galdon-Quiroga, M. Balden, J. Pinzón Acosta, C. Sozzi, T. Bolzonella, G. Neu, Simon Freethy, T. Sehmer, K. Höfler, T. T. Ribeiro, F. Mink, Ursel Fantz, Q. Yang, Jeppe Olsen, M. Wischmeier, P. Mantica, Timothy Goodman, R. Delogu, T. Tala, Panagiotis Tolias, A. Houben, G. Tardini, A. Kirk, T. Odstrcil, R. Fischer, J. Juul Rasmussen, D. Carralero, H. F. Meyer, P. Martin, J. Miettunen, E. Maljaars, Matthew Carr, Z. Yang, G. Pautasso, B. P. Duval, E. Sytova, Stefano Coda, D. Meshcheriakov, Morten Stejner, S. Zoletnik, Thomas Zehetbauer, M. Li, F. Liu, R. Neu, A. Drenik, P. Manz, E. Fable, Otto Asunta, Zhixin Lu, S. Kálvin, Bruce Lipschultz, Vinodh Bandaru, A. Di Siena, Mattia Siccinio, S. Costea, Frank Jenko, Peter Lang, V. Rohde, Manfred Zilker, F. Nabais, H. J. Sun, Chris Hegna, A. Krivska, M. Rott, S. E. Sharapov, Antoine Merle, J. Bernardo, K. Engelhardt, M. Garcia-Munoz, M. Kantor, M. Hölzl, J. M. Santos, L. Guimarais, A. Figuereido, Carlos B. da Silva, Ch. Day, P. David, U. von Toussaint, T. C. Blanken, D. A. Ryan, F. Palermo, Silvio Ceccuzzi, J.-M. Noterdaeme, M. Gobbin, A. Jansen van Vuuren, C.-P. Kasemann, D. Rittich, Wouter Tierens, Taina Kurki-Suonio, C. Martens, R. Riedl, Antti Hakola, A. Czarnecka, F. Hitzler, M. Spolaore, M. Tripský, D. Brida, A. V. Chankin, Alessandro Pau, T. Ilkei, K. Krieger, Emanuele Poli, Florian Laggner, J. F. Rivero-Rodriguez, Wolfgang Jacob, Nengchao Wang, Anne White, S. Kjer Hansen, Stefan Kragh Nielsen, M. Fröschle, R. Bilato, O. Kudlacek, Tobias Görler, A. Stegmeir, Ari Salmi, L. Colas, A. Mlynek, Istvan Cziegler, V. Bobkov, James Buchanan, A. Gräter, T. Luda di Cortemiglia, R. Drube, John Hammer Holm, Giuliana Sias, K. Galazka, Giuseppe Gorini, V. Igochine, B. Vanovac, O. P. Ford, A. Garcia-Carrasco, R. M. McDermott, B. Tal, A. Lebschy, M. Cavedon, Julia Fuchs, E. Viezzer, R. Dux, R.A. Pitts, Svetlana V. Ratynskaia, Aqsa Shabbir, Sergei Kasilov, M. Bernert, S. Saarelma, Gergö Pokol, F. Reimold, Geert Verdoolaege, M. Mayer, Marek Rubel, L. Sanchis-Sanchez, R. Maingi, William Hornsby, U. Plank, C. Cianfarani, N. Vianello, A. Huber, Gustavo Granucci, Didier Mazon, S. Glöggler, J. Simpson, I. Faust, G. L. Ravera, Laurie Porte, Johann Riesch, F. Janky, A Lyssoivan, T. Pütterich, F. Orain, M. Valisa, B. Esposito, C. Gleason-González, Juha Karhunen, M. Valovic, H. Maier, Gábor Cseh, A. Nemes-Czopf, E. Thoren, O. Pan, T. Eich, R. Coelho, M.R. de Baar, E. Strumberger, T. Hellsten, Lionello Marrelli, Boglarka Erdos, Pascale Hennequin, R. Ochoukov, H. Zohm, D. Wagner, Yevgen O. Kazakov, A. Medvedeva, M. G. Dunne, W. Treutterer, N. Leuthold, R. Zagórski, S. Potzel, V. Klevarova, Dirk Reiser, X. Wang, T. Lunt, Meyer, H, Angioni, C, Albert, C, Arden, N, Arredondo Parra, R, Asunta, O, De Baar, M, Balden, M, Bandaru, V, Behler, K, Bergmann, A, Bernardo, J, Bernert, M, Biancalani, A, Bilato, R, Birkenmeier, G, Blanken, T, Bobkov, V, Bock, A, Bolzonella, T, Bortolon, A, Boswirth, B, Bottereau, C, Bottino, A, Van Den Brand, H, Brezinsek, S, Brida, D, Brochard, F, Bruhn, C, Buchanan, J, Buhler, A, Burckhart, A, Camenen, Y, Carlton, D, Carr, M, Carralero, D, Castaldo, C, Cavedon, M, Cazzaniga, C, Ceccuzzi, S, Challis, C, Chankin, A, Chapman, S, Cianfarani, C, Clairet, F, Coda, S, Coelho, R, Coenen, J, Colas, L, Conway, G, Costea, S, Coster, D, Cote, T, Creely, A, Croci, G, Cseh, G, Czarnecka, A, Cziegler, I, D'Arcangelo, O, David, P, Day, C, Delogu, R, De Marne, P, Denk, S, Denner, P, Dibon, M, Di Siena, A, Douai, D, Drenik, A, Drube, R, Dunne, M, Duval, B, Dux, R, Eich, T, Elgeti, S, Engelhardt, K, Erdos, B, Erofeev, I, Esposito, B, Fable, E, Faitsch, M, Fantz, U, Faugel, H, Faust, I, Felici, F, Ferreira, J, Fietz, S, Figuereido, A, Fischer, R, Ford, O, Frassinetti, L, Freethy, S, Froschle, M, Fuchert, G, Fuchs, J, Funfgelder, H, Galazka, K, Galdon-Quiroga, J, Gallo, A, Gao, Y, Garavaglia, S, Garcia-Carrasco, A, Garcia-Munoz, M, Geiger, B, Giannone, L, Gil, L, Giovannozzi, E, Gleason-Gonzalez, C, Gloggler, S, Gobbin, M, Gorler, T, Gomez Ortiz, I, Gonzalez Martin, J, Goodman, T, Gorini, G, Gradic, D, Grater, A, Granucci, G, Greuner, H, Griener, M, Groth, M, Gude, A, Gunter, S, Guimarais, L, Haas, G, Hakola, A, Ham, C, Happel, T, Den Harder, N, Harrer, G, Harrison, J, Hauer, V, Hayward-Schneider, T, Hegna, C, Heinemann, B, Heinzel, S, Hellsten, T, Henderson, S, Hennequin, P, Herrmann, A, Heyn, M, Heyn, E, Hitzler, F, Hobirk, J, Hofler, K, Holzl, M, Hoschen, T, Holm, J, Hopf, C, Hornsby, W, Horvath, L, Houben, A, Huber, A, Igochine, V, Ilkei, T, Ivanova-Stanik, I, Jacob, W, Jacobsen, A, Janky, F, Jansen Van Vuuren, A, Jardin, A, Jaulmes, F, Jenko, F, Jensen, T, Joffrin, E, Kasemann, C, Kallenbach, A, Kalvin, S, Kantor, M, Kappatou, A, Kardaun, O, Karhunen, J, Kasilov, S, Kazakov, Y, Kernbichler, W, Kirk, A, Kjer Hansen, S, Klevarova, V, Kocsis, G, Kohn, A, Koubiti, M, Krieger, K, Krivska, A, Kramer-Flecken, A, Kudlacek, O, Kurki-Suonio, T, Kurzan, B, Labit, B, Lackner, K, Laggner, F, Lang, P, Lauber, P, Lebschy, A, Leuthold, N, Li, M, Linder, O, Lipschultz, B, Liu, F, Liu, Y, Lohs, A, Lu, Z, Luda Di Cortemiglia, T, Luhmann, N, Lunsford, R, Lunt, T, Lyssoivan, A, Maceina, T, Madsen, J, Maggiora, R, Maier, H, Maj, O, Mailloux, J, Maingi, R, Maljaars, E, Manas, P, Mancini, A, Manhard, A, Manso, M, Mantica, P, Mantsinen, M, Manz, P, Maraschek, M, Martens, C, Martin, P, Marrelli, L, Martitsch, A, Mayer, M, Mazon, D, Mccarthy, P, Mcdermott, R, Meister, H, Medvedeva, A, Merkel, R, Merle, A, Mertens, V, Meshcheriakov, D, Meyer, O, Miettunen, J, Milanesio, D, Mink, F, Mlynek, A, Monaco, F, Moon, C, Nabais, F, Nemes-Czopf, A, Neu, G, Neu, R, Nielsen, A, Nielsen, S, Nikolaeva, V, Nocente, M, Noterdaeme, J, Novikau, I, Nowak, S, Oberkofler, M, Oberparleiter, M, Ochoukov, R, Odstrcil, T, Olsen, J, Orain, F, Palermo, F, Pan, O, Papp, G, Paradela Perez, I, Pau, A, Pautasso, G, Penzel, F, Petersson, P, Pinzon Acosta, J, Piovesan, P, Piron, C, Pitts, R, Plank, U, Plaum, B, Ploeckl, B, Plyusnin, V, Pokol, G, Poli, E, Porte, L, Potzel, S, Prisiazhniuk, D, Putterich, T, Ramisch, M, Rasmussen, J, Ratta, G, Ratynskaia, S, Raupp, G, Ravera, G, Refy, D, Reich, M, Reimold, F, Reiser, D, Ribeiro, T, Riesch, J, Riedl, R, Rittich, D, Rivero-Rodriguez, J, Rocchi, G, Rodriguez-Ramos, M, Rohde, V, Ross, A, Rott, M, Rubel, M, Ryan, D, Ryter, F, Saarelma, S, Salewski, M, Salmi, A, Sanchis-Sanchez, L, Santos, J, Sauter, O, Scarabosio, A, Schall, G, Schmid, K, Schmitz, O, Schneider, P, Schrittwieser, R, Schubert, M, Schwarz-Selinger, T, Schweinzer, J, Scott, B, Sehmer, T, Seliunin, E, Sertoli, M, Shabbir, A, Shalpegin, A, Shao, L, Sharapov, S, Sias, G, Siccinio, M, Sieglin, B, Sigalov, A, Silva, A, Silva, C, Silvagni, D, Simon, P, Simpson, J, Smigelskis, E, Snicker, A, Sommariva, C, Sozzi, C, Spolaore, M, Stegmeir, A, Stejner, M, Stober, J, Stroth, U, Strumberger, E, Suarez, G, Sun, H, Suttrop, W, Sytova, E, Szepesi, T, Tal, B, Tala, T, Tardini, G, Tardocchi, M, Teschke, M, Terranova, D, Tierens, W, Thoren, E, Told, D, Tolias, P, Tudisco, O, Treutterer, W, Trier, E, Tripsky, M, Valisa, M, Valovic, M, Vanovac, B, Van Vugt, D, Varoutis, S, Verdoolaege, G, Vianello, N, Vicente, J, Vierle, T, Viezzer, E, Von Toussaint, U, Wagner, D, Wang, N, Wang, X, Weiland, M, White, A, Wiesen, S, Willensdorfer, M, Wiringer, B, Wischmeier, M, Wolf, R, Wolfrum, E, Xiang, L, Yang, Q, Yang, Z, Yu, Q, Zagorski, R, Zammuto, I, Zhang, W, Van Zeeland, M, Zehetbauer, T, Zilker, M, Zoletnik, S, Zohm, H, Meyer, H., Universidad de Sevilla, Departamento de Física Atómica, Molecular y Nuclear, Universidad de Sevilla. RNM138: Física Nuclear Aplicada, Universidad de Sevilla. TEP111: Ingeniería Mecánica, CEA Cadarache, Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut Jean Lamour (IJL), Institut de Chimie du CNRS (INC)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Physique des interactions ioniques et moléculaires (PIIM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique des Plasmas (LPP), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École polytechnique (X)-Sorbonne Université (SU)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Culham Science Centre, Max-Planck-Institut für Plasmaphysik, Department of Applied Physics, Dutch Institute for Fundamental Energy Research, University of Lisbon, Eindhoven University of Technology, National Research Council of Italy, Princeton University, CEA, Forschungszentrum Jülich, Université de Lorraine, CNRS, Agenzia nazionale per le nuove tecnologie, l'energia e lo sviluppo economico sostenibile, University of Warwick, Swiss Federal Institute of Technology Lausanne, University of Innsbruck, University of Wisconsin-Madison, Massachusetts Institute of Technology, Hungarian Academy of Sciences, Soltan Institute for Nuclear Studies, University of York, Karlsruhe Institute of Technology, KTH Royal Institute of Technology, University of Seville, University of Milan - Bicocca, Fusion and Plasma Physics, VTT Technical Research Centre of Finland, Vienna University of Technology, Max-Planck Computing and Data Facility, General Atomics, Université Paris-Saclay, Graz University of Technology, Institut für Grenzflachenverfahrenstechnik und Plasmatechnologie, Danmarks Tekniske Universitet, Budapest University of Technology and Economics, Polish Academy of Sciences, Royal Military Academy, Ghent University, ITER Organization, University of California Davis, Polytechnic University of Turin, Barcelona Supercomputing Center, University College Cork, Chalmers University of Technology, University of Cagliari, ITER, CIEMAT, CAS - Institute of Plasma Physics, Max Planck Institute for Plasma Physics, Aalto-yliopisto, Aalto University, Angioni, C., Albert, C. G., Arden, N., Arredondo Parra, R., Asunta, O., De Baar, M., Balden, M., Bandaru, V., Behler, K., Bergmann, A., Bernardo, J., Bernert, M., Biancalani, A., Bilato, R., Birkenmeier, G., Blanken, T. C., Bobkov, V., Bock, A., Bolzonella, T., Bortolon, A., Boswirth, B., Bottereau, C., Bottino, A., Van Den Brand, H., Brezinsek, S., Brida, D., Brochard, F., Bruhn, C., Buchanan, J., Buhler, A., Burckhart, A., Camenen, Y., Carlton, D., Carr, M., Carralero, D., Castaldo, C., Cavedon, M., Cazzaniga, C., Ceccuzzi, S., Challis, C., Chankin, A., Chapman, S., Cianfarani, C., Clairet, F., Coda, S., Coelho, R., Coenen, J. W., Colas, L., Conway, G. D., Costea, S., Coster, D. P., Cote, T. B., Creely, A., Croci, G., Cseh, G., Czarnecka, A., Cziegler, I., D'Arcangelo, O., David, P., Day, C., Delogu, R., De Marne, P., Denk, S. S., Denner, P., Dibon, M., Di Siena, A., Douai, D., Drenik, A., Drube, R., Dunne, M., Duval, B. P., Dux, R., Eich, T., Elgeti, S., Engelhardt, K., Erdos, B., Erofeev, I., Esposito, B., Fable, E., Faitsch, M., Fantz, U., Faugel, H., Faust, I., Felici, F., Ferreira, J., Fietz, S., Figuereido, A., Fischer, R., Ford, O., Frassinetti, L., Freethy, S., Froschle, M., Fuchert, G., Fuchs, J. C., Funfgelder, H., Galazka, K., Galdon-Quiroga, J., Gallo, A., Gao, Y., Garavaglia, S., Garcia-Carrasco, A., Garcia-Munoz, M., Geiger, B., Giannone, L., Gil, L., Giovannozzi, E., Gleason-Gonzalez, C., Gloggler, S., Gobbin, M., Gorler, T., Gomez Ortiz, I., Gonzalez Martin, J., Goodman, T., Gorini, G., Gradic, D., Grater, A., Granucci, G., Greuner, H., Griener, M., Groth, M., Gude, A., Gunter, S., Guimarais, L., Haas, G., Hakola, A. H., Ham, C., Happel, T., Den Harder, N., Harrer, G. F., Harrison, J., Hauer, V., Hayward-Schneider, T., Hegna, C. C., Heinemann, B., Heinzel, S., Hellsten, T., Henderson, S., Hennequin, P., Herrmann, A., Heyn, M. F., Heyn, E., Hitzler, F., Hobirk, J., Hofler, K., Holzl, M., Hoschen, T., Holm, J. H., Hopf, C., Hornsby, W. A., Horvath, L., Houben, A., Huber, A., Igochine, V., Ilkei, T., Ivanova-Stanik, I., Jacob, W., Jacobsen, A. S., Janky, F., Jansen Van Vuuren, A., Jardin, A., Jaulmes, F., Jenko, F., Jensen, T., Joffrin, E., Kasemann, C. -P., Kallenbach, A., Kalvin, S., Kantor, M., Kappatou, A., Kardaun, O., Karhunen, J., Kasilov, S., Kazakov, Y., Kernbichler, W., Kirk, A., Kjer Hansen, S., Klevarova, V., Kocsis, G., Kohn, A., Koubiti, M., Krieger, K., Krivska, A., Kramer-Flecken, A., Kudlacek, O., Kurki-Suonio, T., Kurzan, B., Labit, B., Lackner, K., Laggner, F., Lang, P. T., Lauber, P., Lebschy, A., Leuthold, N., Li, M., Linder, O., Lipschultz, B., Liu, F., Liu, Y., Lohs, A., Lu, Z., Luda Di Cortemiglia, T., Luhmann, N. C., Lunsford, R., Lunt, T., Lyssoivan, A., Maceina, T., Madsen, J., Maggiora, R., Maier, H., Maj, O., Mailloux, J., Maingi, R., Maljaars, E., Manas, P., Mancini, A., Manhard, A., Manso, M. -E., Mantica, P., Mantsinen, M., Manz, P., Maraschek, M., Martens, C., Martin, P., Marrelli, L., Martitsch, A., Mayer, M., Mazon, D., Mccarthy, P. J., Mcdermott, R., Meister, H., Medvedeva, A., Merkel, R., Merle, A., Mertens, V., Meshcheriakov, D., Meyer, O., Miettunen, J., Milanesio, D., Mink, F., Mlynek, A., Monaco, F., Moon, C., Nabais, F., Nemes-Czopf, A., Neu, G., Neu, R., Nielsen, A. H., Nielsen, S. K., Nikolaeva, V., Nocente, M., Noterdaeme, J. -M., Novikau, I., Nowak, S., Oberkofler, M., Oberparleiter, M., Ochoukov, R., Odstrcil, T., Olsen, J., Orain, F., Palermo, F., Pan, O., Papp, G., Paradela Perez, I., Pau, A., Pautasso, G., Penzel, F., Petersson, P., Pinzon Acosta, J., Piovesan, P., Piron, C., Pitts, R., Plank, U., Plaum, B., Ploeckl, B., Plyusnin, V., Pokol, G., Poli, E., Porte, L., Potzel, S., Prisiazhniuk, D., Putterich, T., Ramisch, M., Rasmussen, J., Ratta, G. A., Ratynskaia, S., Raupp, G., Ravera, G. L., Refy, D., Reich, M., Reimold, F., Reiser, D., Ribeiro, T., Riesch, J., Riedl, R., Rittich, D., Rivero-Rodriguez, J. F., Rocchi, G., Rodriguez-Ramos, M., Rohde, V., Ross, A., Rott, M., Rubel, M., Ryan, D., Ryter, F., Saarelma, S., Salewski, M., Salmi, A., Sanchis-Sanchez, L., Santos, J., Sauter, O., Scarabosio, A., Schall, G., Schmid, K., Schmitz, O., Schneider, P. A., Schrittwieser, R., Schubert, M., Schwarz-Selinger, T., Schweinzer, J., Scott, B., Sehmer, T., Seliunin, E., Sertoli, M., Shabbir, A., Shalpegin, A., Shao, L., Sharapov, S., Sias, G., Siccinio, M., Sieglin, B., Sigalov, A., Silva, A., Silva, C., Silvagni, D., Simon, P., Simpson, J., Smigelskis, E., Snicker, A., Sommariva, C., Sozzi, C., Spolaore, M., Stegmeir, A., Stejner, M., Stober, J., Stroth, U., Strumberger, E., Suarez, G., Sun, H. -J., Suttrop, W., Sytova, E., Szepesi, T., Tal, B., Tala, T., Tardini, G., Tardocchi, M., Teschke, M., Terranova, D., Tierens, W., Thoren, E., Told, D., Tolias, P., Tudisco, O., Treutterer, W., Trier, E., Tripsky, M., Valisa, M., Valovic, M., Vanovac, B., Van Vugt, D., Varoutis, S., Verdoolaege, G., Vianello, N., Vicente, J., Vierle, T., Viezzer, E., Von Toussaint, U., Wagner, D., Wang, N., Wang, X., Weiland, M., White, A. E., Wiesen, S., Willensdorfer, M., Wiringer, B., Wischmeier, M., Wolf, R., Wolfrum, E., Xiang, L., Yang, Q., Yang, Z., Yu, Q., Zagorski, R., Zammuto, I., Zhang, W., Van Zeeland, M., Zehetbauer, T., Zilker, M., Zoletnik, S., Zohm, H., ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society, and EUROfusion MST1 Team

Subjects
Magnetic confinement, Edge-localized modes (ELMs), Nuclear engineering, PLASMAS, Nuclear physics, 01 natural sciences, 010305 fluids & plasmas, ASDEX Upgrade, ITER, MODE, Physics, iter, Divertor, magnetic confinement, Magnetic confinement fusion, mode, Dissipation, Condensed Matter Physics, ddc, Tokamak physics, Física nuclear, tokamak physics, Tokamaks, FLUX, Nuclear and High Energy Physics, Technology and Engineering, DEMO, nuclear fusion, Electron cyclotron resonance, Resonant magnetic perturbations, Physics::Plasma Physics, 0103 physical sciences, Nuclear fusion, ddc:530, 010306 general physics, SOLID TUNGSTEN DIVERTOR, Física [Àrees temàtiques de la UPC], demo, plasmas, solid tungsten divertor, flux, ___, HEAVY ALLOYS, Magnetohydrodynamics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], heavy alloys
Abstract

The ASDEX Upgrade (AUG) programme, jointly run with the EUROfusion MST1 task force, continues to significantly enhance the physics base of ITER and DEMO. Here, the full tungsten wall is a key asset for extrapolating to future devices. The high overall heating power, flexible heating mix and comprehensive diagnostic set allows studies ranging from mimicking the scrape-off-layer and divertor conditions of ITER and DEMO at high density to fully non-inductive operation (q95 = 5.5, ) at low density. Higher installed electron cyclotron resonance heating power 6 MW, new diagnostics and improved analysis techniques have further enhanced the capabilities of AUG. Stable high-density H-modes with MW m−1 with fully detached strike-points have been demonstrated. The ballooning instability close to the separatrix has been identified as a potential cause leading to the H-mode density limit and is also found to play an important role for the access to small edge-localized modes (ELMs). Density limit disruptions have been successfully avoided using a path-oriented approach to disruption handling and progress has been made in understanding the dissipation and avoidance of runaway electron beams. ELM suppression with resonant magnetic perturbations is now routinely achieved reaching transiently . This gives new insight into the field penetration physics, in particular with respect to plasma flows. Modelling agrees well with plasma response measurements and a helically localised ballooning structure observed prior to the ELM is evidence for the changed edge stability due to the magnetic perturbations. The impact of 3D perturbations on heat load patterns and fast-ion losses have been further elaborated. Progress has also been made in understanding the ELM cycle itself. Here, new fast measurements of and Er allow for inter ELM transport analysis confirming that Er is dominated by the diamagnetic term even for fast timescales. New analysis techniques allow detailed comparison of the ELM crash and are in good agreement with nonlinear MHD modelling. The observation of accelerated ions during the ELM crash can be seen as evidence for the reconnection during the ELM. As type-I ELMs (even mitigated) are likely not a viable operational regime in DEMO studies of 'natural' no ELM regimes have been extended. Stable I-modes up to have been characterised using -feedback. Core physics has been advanced by more detailed characterisation of the turbulence with new measurements such as the eddy tilt angle—measured for the first time—or the cross-phase angle of and fluctuations. These new data put strong constraints on gyro-kinetic turbulence modelling. In addition, carefully executed studies in different main species (H, D and He) and with different heating mixes highlight the importance of the collisional energy exchange for interpreting energy confinement. A new regime with a hollow profile now gives access to regimes mimicking aspects of burning plasma conditions and lead to nonlinear interactions of energetic particle modes despite the sub-Alfvénic beam energy. This will help to validate the fast-ion codes for predicting ITER and DEMO. This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014–2018 and 2019–2020 under grant agreement No. 633053. The views and opinions expressed herein do not necessarily reflect those of the European Commission. "Article signat per més de 100 autors/es: H. Meyer, for the AUG Team: D. Aguiam, C. Angioni, C.G. Albert, N. Arden, R. Arredondo Parra, O. Asunta, M. de Baar, M. Balden, V. Bandaru, K. Behler, A. Bergmann, J. Bernardo, M. Bernert, A. Biancalani, R. Bilato, G. Birkenmeier, T.C. Blanken, V. Bobkov, A. Bock, T. Bolzonella, A. Bortolon, B. Böswirth, C. Bottereau, A. Bottino, H. van den Brand, S. Brezinsek, D. Brida, F. Brochard, C. Bruhn, J. Buchanan, A. Buhler, A. Burckhart, Y. Camenen, D. Carlton, M. Carr, D. Carralero, C. Castaldo, M. Cavedon, C. Cazzaniga, S. Ceccuzzi, C. Challis, A. Chankin, S. Chapman, C. Cianfarani, F. Clairet, S. Coda, R. Coelho, J.W. Coenen, L. Colas, G.D. Conway, S. Costea, D.P. Coster, T.B. Cote, A. Creely, G. Croci, G. Cseh, A. Czarnecka, I. Cziegler, O. D'Arcangelo, P. David, C. Day, R. Delogu, P. de Marné, S.S. Denk, P. Denner, M. Dibon, A. Di Siena, D. Douai, A. Drenik, R. Drube, M. Dunne, B.P. Duval, R. Dux, T. Eich, S. Elgeti, K. Engelhardt, B. Erdös, I. Erofeev, B. Esposito, E. Fable, M. Faitsch, U. Fantz, H. Faugel, I. Faust, F. Felici, J. Ferreira, S. Fietz, A. Figuereido, R. Fischer, O. Ford, L. Frassinetti, S. Freethy, M. Fröschle, G. Fuchert, J.C. Fuchs, H. Fünfgelder, K. Galazka, J. Galdon-Quiroga, A. Gallo, Y. Gao, S. Garavaglia, A. Garcia-Carrasco, M. Garcia-Muñoz, B. Geiger, L. Giannone, L. Gil, E. Giovannozzi, C. Gleason-González, S. Glöggler, M. Gobbin, T. Görler, I. Gomez Ortiz, J. Gonzalez Martin, T. Goodman, G. Gorini, D. Gradic, A. Gräter, G. Granucci, H. Greuner, M. Griener, M. Groth, A. Gude, S. Günter, L. Guimarais, G. Haas, A.H. Hakola, C. Ham, T. Happel, N. den Harder, G.F. Harrer, J. Harrison, V. Hauer, T. Hayward-Schneider, C.C. Hegna, B. Heinemann, S. Heinzel, T. Hellsten, S. Henderson, P. Hennequin, A. Herrmann, M.F. Heyn, E. Heyn, F. Hitzler, J. Hobirk, K. Höfler, M. Hölzl, T. Höschen, J.H. Holm, C. Hopf, W.A. Hornsby, L. Horvath, A. Houben, A. Huber, V. Igochine, T. Ilkei, I. Ivanova-Stanik, W. Jacob, A.S. Jacobsen, F. Janky, A. Jansen van Vuuren, A. Jardin, F. Jaulmes, F. Jenko, T. Jensen, E. Joffrin, C.-P. Käsemann, A. Kallenbach, S. Kálvin, M. Kantor, A. Kappatou, O. Kardaun, J. Karhunen, S. Kasilov,, Y. Kazakov, W. Kernbichler, A. Kirk, S. Kjer Hansen, V. Klevarova, G. Kocsis, A. Köhn, M. Koubiti, K. Krieger, A. Krivska, A. Krämer-Flecken, O. Kudlacek, T. Kurki-Suonio, B. Kurzan, B. Labit, K. Lackner, F. Laggner, P.T. Lang, P. Lauber, A. Lebschy, N. Leuthold, M. Li, O. Linder, B. Lipschultz, F. Liu, Y. Liu, A. Lohs, Z. Lu, T. Luda di Cortemiglia, N.C. Luhmann, R. Lunsford, T. Lunt, A. Lyssoivan, T. Maceina, J. Madsen, R. Maggiora, H. Maier, O. Maj, J. Mailloux, R. Maingi, E. Maljaars, P. Manas, A. Mancini, A. Manhard, M.-E. Manso, P. Mantica, M. Mantsinen, P. Manz, M. Maraschek, C. Martens, P. Martin, L. Marrelli, A. Martitsch, M. Mayer, D. Mazon, P.J. McCarthy, R. McDermott, H. Meister, A. Medvedeva, R. Merkel, A. Merle, V. Mertens, D. Meshcheriakov, O. Meyer, J. Miettunen, D. Milanesio, F. Mink, A. Mlynek, F. Monaco, C. Moon, F. Nabais, A. Nemes-Czopf, G. Neu, R. Neu, A.H. Nielsen, S.K. Nielsen, V. Nikolaeva, M. Nocente, J.-M. Noterdaeme, I. Novikau, S. Nowak, M. Oberkofler, M. Oberparleiter, R. Ochoukov, T. Odstrcil, J. Olsen, F. Orain, F. Palermo, O. Pan, G. Papp, I. Paradela Perez, A. Pau, G. Pautasso, F. Penzel, P. Petersson, J. Pinzón Acosta, P. Piovesan, C. Piron, R. Pitts, U. Plank, B. Plaum, B. Ploeckl, V. Plyusnin, G. Pokol, E. Poli, L. Porte, S. Potzel, D. Prisiazhniuk, T. Pütterich, M. Ramisch, J. Rasmussen, G.A. Rattá, S. Ratynskaia, G. Raupp, G.L. Ravera, D. Réfy, M. Reich, F. Reimold, D. Reiser, T. Ribeiro, J. Riesch, R. Riedl, D. Rittich, J.F. Rivero-Rodriguez, G. Rocchi, M. Rodriguez-Ramos, V. Rohde, A. Ross1, M. Rott, M. Rubel, D. Ryan, F. Ryter, S. Saarelma, M. Salewski, A. Salmi, L. Sanchis-Sanchez, J. Santos, O. Sauter, A. Scarabosio, G. Schall, K. Schmid, O. Schmitz, P.A. Schneider, R. Schrittwieser, M. Schubert, T. Schwarz-Selinger, J. Schweinzer, B. Scott, T. Semer, E. Seliunin, M. Sertoli, A. Shabbir, A. Shalpegin, L. Shao, S. Sharapov, G. Sias, M. Siccinio, B. Sieglin, A. Sigalov, A. Silva, C. Silva, D. Silvagni, P. Simon, J. Simpson, E. Smigelskis, A. Snicker, C. Sommariva, C. Sozzi, M. Spolaore, A. Stegmeir, M. Stejner, J. Stober, U. Stroth, E. Strumberger, G. Suarez, H.-J. Sun, W. Suttrop, E. Sytova, T. Szepesi, B. Tál, T. Tala, G. Tardini, M. Tardocchi, M. Teschke, D. Terranova, W. Tierens, E. Thorén, D. Told, P. Tolias, O. Tudisco, W. Treutterer, E. Trier, M. Tripský, M. Valisa, M. Valovic, B. Vanovac, D. van Vugt, S. Varoutis, G. Verdoolaege, N. Vianello, J. Vicente, T. Vierle, E. Viezzer, U. von Toussaint, D. Wagner, N. Wang, X. Wang, M. Weiland, A.E. White, S. Wiesen, M. Willensdorfer, B. Wiringer, M. Wischmeier, R. Wolf, E. Wolfrum, L. Xiang, Q. Yang, Z. Yang, Q. Yu, R. Zagórski, I. Zammuto, W. Zhang, M. van Zeeland, T. Zehetbauer, M. Zilker, S. Zoletnik, H. Zohm and the EUROfusion MST1 Team55

Published
2018

35. Prediction of ohmic losses in miter bend polarizers

Author

W. Kasparek, J. Stober, D. Wagner, F. Leuterer, Carsten Lechte, and ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society

Subjects
010302 applied physics, Materials science, business.industry, Physics, QC1-999, Polarizer, 01 natural sciences, 010305 fluids & plasmas, law.invention, Miter joint, law, 0103 physical sciences, Optoelectronics, business, Ohmic contact
Published
2018

36. Assessment of the baseline scenario at q95~3 for ITER

Author

Hajime Urano, Francesca Turco, P. de Vries, Itpa-Ios Tg members, S.H. Kim, J. Stober, I. Nunes, E. Joffrin, T. C. Luce, T. Pütterich, Shunsuke Ide, J. Schweinzer, C.E. Kessel, F.G. Rimini, W. M. Solomon, P. J. Lomas, A. C. C. Sips, J. Hobirk, Jet Contributors, S.M. Wolfe, Experts, JET Contributors, ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society, DIII-D Team, C-Mod Team, JT-U Team, and ITPA-IOS TG Members and Experts

Subjects
Nuclear and High Energy Physics, Tokamak, law, Nuclear engineering, 0103 physical sciences, 010306 general physics, Condensed Matter Physics, Baseline (configuration management), 01 natural sciences, 7. Clean energy, 010305 fluids & plasmas, law.invention
Abstract

The International Tokamak Physics Activity topical group on integrated operational scenarios has compiled a database of stationary H-mode discharges at q(95) similar to 3 from AUG, C-Mod, DIII-D, J ...

Published
2018

37. Parameter dependences of small edge localized modes (ELMs)

Author

P. Manz, Harry M. Meyer, T. Eich, M. Bernert, Peter Lang, Benoit Labit, Florian Laggner, Friedrich Aumayr, B. Kurzan, J. Stober, E. Wolfrum, M. G. Dunne, M. Cavedon, G. F. Harrer, Harrer, G, Wolfrum, E, Dunne, M, Manz, P, Cavedon, M, Lang, P, Kurzan, B, Eich, T, Labit, B, Stober, J, Meyer, H, Bernert, M, Laggner, F, Aumayr, F, EUROfusion MST1 Team, and ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society

Subjects
Physics, Nuclear and High Energy Physics, Condensed matter physics, Edge (geometry), magnetic shear, Condensed Matter Physics, 01 natural sciences, edge localized mode, 010305 fluids & plasmas, type-II, pellet, 0103 physical sciences, ballooning mode, 010306 general physics, ballooning, small ELM
Abstract

The development of small edge localized mode (ELM) scenarios is important in order to reduce the strain on plasma facing components. One such scenario can be found at high densities, in highly shaped, close to double-null plasmas in ASDEX Upgrade, showing small ELMs characterized by a frequency fELM > 300 Hz and a low power loss. Changing from gas fuelling to pellet fuelling results in edge profiles in which the collisionality of pedestal top and separatrix are decoupled. While the pedestal top values remain unchanged, only the phases with low separatrix and scrape-off layer (SOL) density show large ELMs with small ELMs in between. In phases with high separatrix density the small ELMs increase in amplitude and large ELMs do not occur. Similarly, a change in vertical plasma position by only ∼2 cm downwards, at constant ne,sep reduces the size of small ELMs while the large ELMs appear more intense. A possible explanation of this behaviour could be the influence of the drive and the stabilization of modes positioned close to the separatrix. When these small ELM modes cause enough transport, they flatten the gradient region around the separatrix and thereby consequently narrow the effective pedestal width. Because a narrower pedestal is more stable against global PB modes, the stability boundary is shifted towards higher pressure gradients and type-I ELMs do not occur. It is shown that a higher ne,sep increases the amplitude of small ELMs and, in agreement with basic ballooning mode theory, a higher local magnetic shear reduces their amplitude.

Published
2018

38. Actuator management for ECRH at ASDEX Upgrade

Author

J. Stober, C. J. Rapson, W. Treutterer, M. Reich, and ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society

Subjects
Long pulse, Computer science, business.industry, Mechanical Engineering, Control engineering, 01 natural sciences, 7. Clean energy, Automation, 010305 fluids & plasmas, Nuclear Energy and Engineering, ASDEX Upgrade, Software deployment, Control system, 0103 physical sciences, General Materials Science, 010306 general physics, Actuator, business, Civil and Structural Engineering
Abstract

Automated actuator management will be necessary on long pulse fusion experiments to adjust to unforeseen plasma events and unpredictable actuator availability. However, as a control problem, actuator management is underdeveloped in the fusion community. This contribution proposes an algorithm based on a control hierarchy and a cost function to optimally allocate scarce actuator resources to various objectives in real-time. Details are given on the development and offline testing which have been completed ready for deployment at ASDEX Upgrade. Electron Cyclotron Resonance Heating (ECRH) is particularly relevant for actuator management due to its localised deposition which can flexibly target specific regions of the plasma for different effects such as non-inductive current drive, impurity regulation, control of MHD modes and of course heating. A further motivation is that automated actuator management will simplify the setup of ECRH, in keeping with the long term goal of integrating MHD control as a routine part of ASDEX Upgrade experiments.

Published
2015

39. Status, Operation, and Extension of the ECRH System at ASDEX Upgrade

Author

F. Leuterer, Burkhard Plaum, W. Kasparek, M. Schubert, W. Treutterer, C. J. Rapson, V. E. Zapevalov, G. Gantenbein, Stefan Müller, A. V. Chirkov, M. Reich, H. Schütz, V. I. Malygin, Gregory G. Denisov, John Jelonnek, J. Stober, H. Zohm, Aleksandr Grigorievich Litvak, Manfred Thumm, D. Wagner, V. O. Nichiporenko, F. Monaco, T.A. Scherer, L. G. Popov, Timothy Goodman, Andreas Meier, Carsten Lechte, M. Münich, E. A. Solyanova, S. A. Malygin, V. E. Myasnikov, E. M. Tai, and ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society

Subjects
Physics, Radiation, business.industry, Nuclear engineering, Power deposition, Electrical engineering, Plasma, Condensed Matter Physics, 01 natural sciences, 7. Clean energy, Electron cyclotron resonance, 010305 fluids & plasmas, Upgrade, ASDEX Upgrade, 0103 physical sciences, Electrical and Electronic Engineering, 010306 general physics, business, Instrumentation
Abstract

The upgraded electron cyclotron resonance heating (ECRH) system at ASDEX Upgrade (AUG) has been routinely used with eight gyrotrons during the last experimental campaign. A further upgrade will replace the existing system of four short-pulse (140 GHz, 2 s, 500 kW) gyrotrons. The final goal is to have around 6.5–7 MW at 140 GHz (or 5.5 MW at 105 GHz) from eight units available in the plasma during the whole AUG discharge (10 s). The system operates at 140 and 105 GHz with X2, O2 and X3 schemes. For B > 3 T also an ITER-like O1-scenario can be run using the 105 GHz option. Four of the eight launching antennas are capable of fast poloidal movements necessary for real-time control of the location of power deposition.

Published
2015

40. En route to high-performance discharges: Insights & guidance from high-realism gyrokinetics

Author

T. Görler, A. Di Siena, H. Doerk, T. Happel, S.J. Freethy, I.-G. Farcas, A. Bañón Navarro, R. Bilato, A. Bock, J. Citrin, G.D. Conway, A. Creely, P. Hennequin, F. Jenko, T. Johnson, C. Lechte, T. Neckel, E. Poli, M. Schneider, E. Sonnendruecker, J. Stober, A.E. White, ASDEX-Upgrade-Team, JET-Contributors, and Department of Informatics

Subjects
ddc
Published
2017

41. Extension of heating and pulse power capabilities at ASDEX upgrade

Author

J. Stober, Jean-Marie Noterdaeme, Christian Hopf, Igor Goldstein, N. Arden, A. Kallenbach, C.-P. Käsemann, and ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society

Subjects
Heating power, Materials science, Mechanical Engineering, Divertor, Nuclear engineering, Magnetic confinement fusion, Pulsed power, Fusion power, 7. Clean energy, 01 natural sciences, 010305 fluids & plasmas, Power (physics), Nuclear Energy and Engineering, ASDEX Upgrade, 13. Climate action, Range (aeronautics), 0103 physical sciences, General Materials Science, 010306 general physics, Civil and Structural Engineering
Abstract

One of the biggest challenges for a fusion reactor with magnetic confinement is the controlled removal of the heating power. ASDEX Upgrade (AUG) is one of the leading experiments in this area and investigates integrated solutions that combine high heating power and wall materials suitable for reactors. A measure of the challenge to remove the power in the divertor region is given by the normalized output power. In AUG it is already 2/3 of the value expected for a reactor. To increase it to the range of the values intended for ITER and DEMO, the present AUG program combines the rise of the central heating power by ECRH, ICRF and NBI with an enhancement and optimization of the power supply installation.

Published
2017
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42. A comparison of the impact of central ECRH and central ICRH on the tungsten behaviour in ASDEX Upgrade H-mode plasmas

Author

T. Odstrcil, J. Stober, V. Bobkov, R. Bilato, M. Sertoli, C. Angioni, A. Loarte, Th. Pütterich, R. Ochoukov, and ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society

Subjects
Nuclear and High Energy Physics, Materials science, Cyclotron resonance, Condensed Matter Physics, 01 natural sciences, 7. Clean energy, Electron cyclotron resonance, Neutral beam injection, 010305 fluids & plasmas, ASDEX Upgrade, Heat flux, Physics::Plasma Physics, 0103 physical sciences, Dielectric heating, Atomic physics, 010306 general physics, Ion cyclotron resonance, Power density
Abstract

A comparison of the impact of additional central electron cyclotron resonance heating (ECRH) and ion cyclotron resonance heating (ICRH) on the behaviour of the tungsten (W) density in the core of H-mode plasmas heated with neutral beam injection (NBI) is performed in ASDEX Upgrade. Both localized and broad profiles of the power density of the ECRH have been obtained, where broad profiles reproduce the profile shape of the ICRH power density, which is applied with a hydrogen minority heating scheme. In contrast to ECRH, which produces direct electron heating only, ICRH eventually heats both electrons and ions in almost equal fractions. It is found that both additional RF heating systems reduce the peaking of the W density profile with increasing central RF heating power. Approximately the same values of W density peaking are obtained when the same values of electron heating are produced by the two RF heating systems, which implies that less total heating power is required with ECRH than with ICRH to reduce the W density peaking. A related modelling activity shows that an important ingredient to explain the experimentally observed trend is the variation of the turbulent W diffusion as a function of the electron to ion heat flux ratio. Additional effects are connected with the more favorable W neoclassical transport convection in the presence of ICRH, produced by the combination of stronger central ion temperature gradients and the impact of the H minority on the W poloidal density asymmetry.

Published
2017

43. Experiments on actuator management and integrated control at ASDEX Upgrade

Author

M. Reich, C. Galperti, C. J. Rapson, J. Stober, M. Lennholm, Olivier Sauter, W. Treutterer, M. Maraschek, Peter Lang, B. Plöckl, E. Maljaars, Faa Federico Felici, ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society, and Control Systems Technology

Subjects
Computer science, Density, Atmospheric-pressure plasma, Actuator management, 01 natural sciences, 010305 fluids & plasmas, law.invention, Pellet, ASDEX Upgrade, Control theory, law, Gyrotron, 0103 physical sciences, General Materials Science, 010306 general physics, Civil and Structural Engineering, Coupling, Flexibility (engineering), Radiation, Mechanical Engineering, Multivariable calculus, Divertor, Integrated control, DCS, ECRH, Nuclear Energy and Engineering, NTM, Actuator
Abstract

The established field of integrated multivariable control promises improved performance and stability for strongly coupled processes, given a control-oriented model of the system. Fusion plasmas are strongly coupled, but there is currently no model which accurately reflects the nature of these complex interactions. Therefore, experiments were performed specifically to investigate coupling between controlled parameters, as a step towards designing integrated controllers in the future. The parameters chosen were core density, divertor neutral pressure and divertor temperature. For control of the plasma pressure and Neoclassical Tearing Modes, where a simple model of the coupling is known, it will be shown that linking the two controllers gives reliably good plasma performance. An additional complication with integrated control is that limited actuator resources are often oversubscribed when trying to control multiple parameters simultaneously. In order to achieve the optimum result, some form of actuator management is a pre-requisite for integrated control. An algorithm has been developed to automatically allocate Electron Cyclotron Resonant Heating gyrotrons to targets, by evaluating a cost function in real-time. Results will be shown to demonstrate the flexibility of this routine to changes in plasma state, gyrotron availability and the goals of the physics experiment.

Published
2017

44. Measurements of the t(t)over-bar production cross section in lepton plus jets final states in pp collisions at 8 and ratio of 8 to 7 cross sections

Author

Khachatryan, V. Sirunyan, A. M. Tumasyan, A. Adam, W. and Asilar, E. Bergauer, T. Brandstetter, J. Brondolin, E. and Dragicevic, M. Ero, J. Flechl, M. Friedl, M. Fruhwirth, R. Ghete, V. M. Hartl, C. Hormann, N. Hrubec, J. and Jeitler, M. Knunz, V. Konig, A. Krammer, M. Kratschmer, I. Liko, D. Matsushita, T. Mikulec, I. Rabady, D. and Rahbaran, B. Rohringer, H. Schieck, J. Schofbeck, R. and Strauss, J. Treberer-Treberspurg, W. Waltenberger, W. Wulz, C. -E. Mossolov, V. Shumeiko, N. Suarez Gonzalez, J. and Alderweireldt, S. Cornelis, T. De Wolf, E. A. Janssen, X. and Knutsson, A. Lauwers, J. Luyckx, S. Van De Klundert, M. and Van Haevermaet, H. Van Mechelen, P. Van Remortel, N. Van Spilbeeck, A. Abu Zeid, S. Blekman, F. D'Hondt, J. Daci, N. Bruyn, I. De Deroover, K. Heracleous, N. Keaveney, J. and Lowette, S. Maes, M. Moreels, L. Olbrechts, A. and Python, Q. Strom, D. Tavernier, S. Van Doninck, W. Van Mulders, P. Van Onsem, G. P. Van Parijs, I. Barria, P. and Brun, H. Caillol, C. Clerbaux, B. De Lentdecker, G. and Fasanella, G. Favart, L. Grebenyuk, A. Karapostoli, G. and Lenzi, T. Leonard, A. Maerschalk, T. Marinov, A. Pernie, L. Randle-conde, A. Reis, T. Seva, T. Vander Velde, C. and Vanlaer, P. Yonamine, R. Zenoni, F. Zhang, F. and Beernaert, K. Benucci, L. Cimmino, A. Costantini, S. and Crucy, S. Dobur, D. Fagot, A. Garcia, G. Gul, M. and Mccartin, J. Ocampo Rios, A. A. Poyraz, D. Ryckbosch, D. and Salva, S. Sigamani, M. Strobbe, N. Tytgat, M. Van Driessche, W. Yazgan, E. Zaganidis, N. Basegmez, S. and Beluffi, C. Bondu, O. Brochet, S. Bruno, G. Caudron, A. and Ceard, L. Da Silveira, G. G. Delaere, C. Favart, D. and Forthomme, L. Giammanco, A. Hollar, J. Jafari, A. Jez, P. Komm, M. Lemaitre, V. Mertens, A. Musich, M. and Nuttens, C. Perrini, L. Pin, A. Piotrzkowski, K. Popov, A. Quertenmont, L. Selvaggi, M. Vidal Marono, M. Beliy, N. Hammad, G. H. Alda Junior, W. L. Alves, F. L. Alves, G. A. Brito, L. Correa Martins Junior, M. Hamer, M. and Hensel, C. Mora Herrera, C. Moraes, A. Pol, M. E. and Rebello Teles, P. Belchior Batista Das Chagas, E. Carvalho, W. and Chinellato, J. Custodio, A. Da Costa, E. M. De Jesus Damiao, D. De Oliveira Martins, C. Fonseca De Souza, S. and Huertas Guativa, L. M. Malbouisson, H. Matos Figueiredo, D. and Mundim, L. Nogima, H. Prado Da Silva, W. L. Santoro, A. and Sznajder, A. Tonelli Manganote, E. J. Vilela Pereira, A. and Ahuja, S. Bernardes, C. A. De Souza Santos, A. Dogra, S. and Fernandez Perez Tomei, T. R. Gregores, E. M. Mercadante, P. G. and Moon, C. S. Novaes, S. F. Padula, Sandra S. Romero Abad, D. Ruiz Vargas, J. C. Aleksandrov, A. Hadjiiska, R. and Iaydjiev, P. Rodozov, M. Stoykova, S. Sultanov, G. and Vutova, M. Dimitrov, A. Glushkov, I. Litov, L. Pavlov, B. Petkov, P. Ahmad, M. Bian, J. G. Chen, G. M. and Chen, H. S. Chen, M. Cheng, T. Du, R. Jiang, C. H. and Plestina, R. Romeo, F. Shaheen, S. M. Spiezia, A. Tao, J. Wang, C. Wang, Z. Zhang, H. Asawatangtrakuldee, C. and Ban, Y. Li, Q. Liu, S. Mao, Y. Qian, S. J. Wang, D. Xu, Z. Avila, C. Cabrera, A. Chaparro Sierra, L. F. and Florez, C. Gomez, J. P. Gomez Moreno, B. Sanabria, J. C. and Godinovic, N. Lelas, D. Puljak, I. Ribeiro Cipriano, P. M. Antunovic, Z. Kovac, M. Brigljevic, V. Kadija, K. and Luetic, J. Micanovic, S. Sudic, L. Attikis, A. and Mavromanolakis, G. Mousa, J. Nicolaou, C. Ptochos, F. and Razis, P. A. Rykaczewski, H. Bodlak, M. Finger, M. and Finger, Jr., M. Abdelalim, A. A. Awad, A. El Sawy, M. and Mahrous, A. Radi, A. Calpas, B. Kadastik, M. Murumaa, M. and Raidal, M. Tiko, A. Veelken, C. Eerola, P. Pekkanen, J. Voutilainen, M. Harkonen, J. Karimaki, V. Kinnunen, R. Lampen, T. Lassila-Perini, K. Lehti, S. Linden, T. and Luukka, P. Maenpaa, T. Peltola, T. Tuominen, E. and Tuominiemi, J. Tuovinen, E. Wendland, L. Talvitie, J. and Tuuva, T. Besancon, M. Couderc, F. Dejardin, M. Denegri, D. Fabbro, B. Faure, J. L. Favaro, C. Ferri, F. and Ganjour, S. Givernaud, A. Gras, P. Hamel de Monchenault, G. and Jarry, P. Locci, E. Machet, M. Malcles, J. Rander, J. Rosowsky, A. Titov, M. Zghiche, A. Antropov, I. and Baffioni, S. Beaudette, F. Busson, P. Cadamuro, L. and Chapon, E. Charlot, C. Dahms, T. Davignon, O. Filipovic, N. Florent, A. Granier de Cassagnac, R. Lisniak, S. and Mastrolorenzo, L. Mine, P. Naranjo, I. N. Nguyen, M. and Ochando, C. Ortona, G. Paganini, P. Pigard, P. Regnard, S. Salerno, R. Sauvan, J. B. Sirois, Y. Strebler, T. and Yilmaz, Y. Zabi, A. Agram, J. -L. Andrea, J. Aubin, A. and Bloch, D. Brom, J. -M. Buttignol, M. Chabert, E. C. and Chanon, N. Collard, C. Conte, E. Coubez, X. Fontaine, J. -C. Gele, D. Goerlach, U. Goetzmann, C. Le Bihan, A. -C. and Merlin, J. A. Skovpen, K. Van Hove, P. Gadrat, S. and Beauceron, S. Bernet, C. Boudoul, G. Bouvier, E. and Carrillo Montoya, C. A. Chierici, R. Contardo, D. Courbon, B. Depasse, P. El Mamouni, H. Fan, J. Fay, J. and Gascon, S. Gouzevitch, M. Ille, B. Lagarde, F. Laktineh, I. B. Lethuillier, M. Mirabito, L. Pequegnot, A. L. and Perries, S. Ruiz Alvarez, J. D. Sabes, D. Sgandurra, L. and Sordini, V. Vander Donckt, M. Verdier, P. Viret, S. and Toriashvili, T. Tsamalaidze, Z. Autermann, C. Beranek, S. and Edelhoff, M. Feld, L. Heister, A. Kiesel, M. K. and Klein, K. Lipinski, M. Ostapchuk, A. Preuten, M. and Raupach, F. Schael, S. Schulte, J. F. Verlage, T. Weber, H. Wittmer, B. Zhukov, V. Ata, M. Brodski, M. and Dietz-Laursonn, E. Duchardt, D. Endres, M. Erdmann, M. and Erdweg, S. Esch, T. Fischer, R. Guth, A. Hebbeker, T. and Heidemann, C. Hoepfner, K. Klingebiel, D. Knutzen, S. and Kreuzer, P. Merschmeyer, M. Meyer, A. Millet, P. and Olschewski, M. Padeken, K. Papacz, P. Pook, T. Radziej, M. Reithler, H. Rieger, M. Scheuch, F. Sonnenschein, L. and Teyssier, D. Thuer, S. Cherepanov, V. Erdogan, Y. and Flugge, G. Geenen, H. Geisler, M. Hoehle, F. Kargoll, B. and Kress, T. Kuessel, Y. Kunsken, A. Lingemann, J. and Nehrkorn, A. Nowack, A. Nugent, I. M. Pistone, C. Pooth, O. Stahl, A. Aldaya Martin, M. Asin, I. Bartosik, N. and Behnke, O. Behrens, U. Bell, A. J. Borras, K. Burgmeier, A. Campbell, A. Choudhury, S. Costanza, F. Diez Pardos, C. Dolinska, G. Dooling, S. Dorland, T. Eckerlin, G. and Eckstein, D. Eichhorn, T. Flucke, G. Gallo, E. Garay Garcia, J. Geiser, A. Gizhko, A. Gunnellini, P. Hauk, J. and Hempel, M. Jung, H. Kalogeropoulos, A. Karacheban, O. and Kasemann, M. Katsas, P. Kieseler, J. Kleinwort, C. and Korol, I. Lange, W. Leonard, J. Lipka, K. Lobanov, A. and Lohmann, W. Mankel, R. Marfin, I. Melzer-Pellmann, I. -A. Meyer, A. B. Mittag, G. Mnich, J. Mussgiller, A. and Naumann-Emme, S. Nayak, A. Ntomari, E. Perrey, H. Pitzl, D. Placakyte, R. Raspereza, A. Roland, B. Sahin, M. O-. and Saxena, P. Schoerner-Sadenius, T. Schroder, M. Seitz, C. and Spannagel, S. Trippkewitz, K. D. Walsh, R. Wissing, C. and Blobel, V. Centis Vignali, M. Draeger, A. R. Erfle, J. and Garutti, E. Goebel, K. Gonzalez, D. Gorner, M. and Haller, J. Hoffmann, M. Hoing, R. S. Junkes, A. Klanner, R. Kogler, R. Kovalchuk, N. Lapsien, T. Lenz, T. and Marchesini, I. Marconi, D. Meyer, M. Nowatschin, D. Ott, J. Pantaleo, F. Peiffer, T. Perieanu, A. Pietsch, N. and Poehlsen, J. Rathjens, D. Sander, C. Scharf, C. and Schettler, H. Schleper, P. Schlieckau, E. Schmidt, A. and Schwandt, J. Sola, V. Stadie, H. Steinbruck, G. Tholen, H. Troendle, D. Usai, E. Vanelderen, L. Vanhoefer, A. and Vormwald, B. Akbiyik, M. Barth, C. Baus, C. Berger, J. Boser, C. Butz, E. Chwalek, T. Colombo, F. De Boer, W. Descroix, A. Dierlamm, A. Fink, S. Frensch, F. and Friese, R. Giffels, M. Gilbert, A. Haitz, D. and Hartmann, F. Heindl, S. M. Husemann, U. Katkov, I. and Kornmayer, A. Lobelle Pardo, P. Maier, B. Mildner, H. and Mozer, M. U. Muller, T. Muller, Th. Plagge, M. Quast, G. and Rabbertz, K. Rocker, S. Roscher, F. Sieber, G. and Simonis, H. J. Stober, F. M. Ulrich, R. Wagner-Kuhr, J. and Wayand, S. Weber, M. Weiler, T. Wohrmann, C. Wolf, R. and Anagnostou, G. Daskalakis, G. Geralis, T. and Giakoumopoulou, V. A. Kyriakis, A. Loukas, D. Psallidas, A. and Topsis-Giotis, I. Agapitos, A. Kesisoglou, S. and Panagiotou, A. Saoulidou, N. Tziaferi, E. Evangelou, I. and Flouris, G. Foudas, C. Kokkas, P. Loukas, N. Manthos, N. and Papadopoulos, I. Paradas, E. Strologas, J. Bencze, G. and Hajdu, C. Hazi, A. Hidas, P. Horvath, D. Sikler, F. and Veszpremi, V. Vesztergombi, G. Zsigmond, A. J. Beni, N. and Czellar, S. Karancsi, J. Molnar, J. Szillasi, Z. and Bartok, M. Makovec, A. Raics, P. Trocsanyi, Z. L. and Ujvari, B. Mal, P. Mandal, K. Sahoo, D. K. Sahoo, N. and Swain, S. K. Bansal, S. Beri, S. B. Bhatnagar, V. and Chawla, R. Gupta, R. Bhawandeep, U. Kalsi, A. K. Kaur, A. Kaur, M. Kumar, R. Mehta, A. Mittal, M. Singh, J. B. Walia, G. Kumar, Ashok Bhardwaj, A. Choudhary, B. C. and Garg, R. B. Kumar, A. Malhotra, S. Naimuddin, M. and Nishu, N. Ranjan, K. Sharma, R. Sharma, V. Bhattacharya, S. Chatterjee, K. Dey, S. Dutta, S. Jain, Sa. and Majumdar, N. Modak, A. Mondal, K. Mukherjee, S. and Mukhopadhyay, S. Roy, A. Roy, D. Chowdhury, S. Roy and Sarkar, S. Sharan, M. Abdulsalam, A. Chudasama, R. and Dutta, D. Jha, V. Kumar, V. Mohanty, A. K. Pant, L. M. and Shukla, P. Topkar, A. Aziz, T. Banerjee, S. Bhowmik, S. Chatterjee, R. M. Dewanjee, R. K. Dugad, S. Ganguly, S. Ghosh, S. Guchait, M. Gurtu, A. Kole, G. Kumar, S. Mahakud, B. Maity, M. Majumder, G. Mazumdar, K. and Mitra, S. Mohanty, G. B. Parida, B. Sarkar, T. Sur, N. and Sutar, B. Wickramage, N. Chauhan, S. Dube, S. and Kothekar, K. Sharma, S. Bakhshiansohi, H. Behnamian, H. and Etesami, S. M. Fahim, A. Goldouzian, R. Khakzad, M. and Mohammadi Najafabadi, M. Naseri, M. Paktinat Mehdiabadi, S. and Rezaei Hosseinabadi, F. Safarzadeh, B. Zeinali, M. Felcini, M. Grunewald, M. Abbrescia, M. Calabria, C. Caputo, C. and Colaleo, A. Creanza, D. Cristella, L. De Filippis, N. and De Palma, M. Fiore, L. Iaselli, G. Maggi, G. Maggi, M. Miniello, G. My, S. Nuzzo, S. Pompili, A. and Pugliese, G. Radogna, R. Ranieri, A. Selvaggi, G. and Silvestris, L. Venditti, R. Verwilligen, P. Abbiendi, G. and Battilana, C. Benvenuti, A. C. Bonacorsi, D. and Braibant-Giacomelli, S. Brigliadori, L. Campanini, R. and Capiluppi, P. Castro, A. Cavallo, F. R. Chhibra, S. S. and Codispoti, G. Cuffiani, M. Dallavalle, G. M. Fabbri, F. and Fanfani, A. Fasanella, D. Giacomelli, P. Grandi, C. and Guiducci, L. Marcellini, S. Masetti, G. Montanari, A. and Navarria, F. L. Perrotta, A. Rossi, A. M. Rovelli, T. and Siroli, G. P. Tosi, N. Travaglini, R. Cappello, G. and Chiorboli, M. Costa, S. Di Mattia, A. Giordano, F. and Potenza, R. Tricomi, A. Tuve, C. Barbagli, G. Ciulli, V. and Civinini, C. D'Alessandro, R. Focardi, E. Gonzi, S. and Gori, V. Lenzi, P. Meschini, M. Paoletti, S. Sguazzoni, G. Tropiano, A. Viliani, L. Benussi, L. Bianco, S. and Fabbri, F. Piccolo, D. Primavera, F. Calvelli, V. Ferro, F. Lo Vetere, M. Monge, M. R. Robutti, E. Tosi, S. and Brianza, L. Dinardo, M. E. Fiorendi, S. Gennai, S. and Gerosa, R. Ghezzi, A. Govoni, P. Malvezzi, S. Manzoni, R. A. Marzocchi, B. Menasce, D. Moroni, L. Paganoni, M. and Pedrini, D. Ragazzi, S. Redaelli, N. Tabarelli de Fatis, T. Buontempo, S. Cavallo, N. Di Guida, S. Esposito, M. and Fabozzi, F. Iorio, A. O. M. Lanza, G. Lista, L. and Meola, S. Merola, M. Paolucci, P. Sciacca, C. Thyssen, F. Azzi, P. Bacchetta, N. Benato, L. Bisello, D. and Boletti, A. Branca, A. Carlin, R. Checchia, P. and Dall'Osso, M. Dorigo, T. Dosselli, U. Gasparini, F. and Gasparini, U. Gozzelino, A. Kanishchev, K. Lacaprara, S. and Margoni, M. Meneguzzo, A. T. Pazzini, J. Pozzobon, N. and Ronchese, P. Simonetto, F. Torassa, E. Tosi, M. Ventura, S. Zanetti, M. Zotto, P. Zucchetta, A. Zumerle, G. and Braghieri, A. Magnani, A. Montagna, P. Ratti, S. P. Re, V. Riccardi, C. Salvini, P. Vai, I. Vitulo, P. and Alunni Solestizi, L. Biasini, M. Bilei, G. M. Ciangottini, D. Fano, L. Lariccia, P. Mantovani, G. Menichelli, M. and Saha, A. Santocchia, A. Androsov, K. Azzurri, P. and Bagliesi, G. Bernardini, J. Boccali, T. Castaldi, R. and Ciocci, M. A. Dell'Orso, R. Donato, S. Fedi, G. Foa, L. and Giassi, A. Grippo, M. T. Ligabue, F. Lomtadze, T. and Martini, L. Messineo, A. Palla, F. Rizzi, A. and Savoy-Navarro, A. Serban, A. T. Spagnolo, P. Tenchini, R. and Tonelli, G. Venturi, A. Verdini, P. G. Barone, L. and Cavallari, F. D'imperio, G. Del Re, D. Diemoz, M. Gelli, S. Jorda, C. Longo, E. Margaroli, F. Meridiani, P. and Organtini, G. Paramatti, R. Preiato, F. Rahatlou, S. and Rovelli, C. Santanastasio, F. Traczyk, P. Amapane, N. and Arcidiacono, R. Argiro, S. Arneodo, M. Bellan, R. Biino, C. Cartiglia, N. Costa, M. Covarelli, R. Degano, A. and Demaria, N. Finco, L. Kiani, B. Mariotti, C. Maselli, S. and Migliore, E. Monaco, V. Monteil, E. Obertino, M. M. and Pacher, L. Pastrone, N. Pelliccioni, M. Pinna Angioni, G. L. and Ravera, F. Romero, A. Ruspa, M. Sacchi, R. Solano, A. Staiano, A. Tamponi, U. Belforte, S. Candelise, V. and Casarsa, M. Cossutti, F. Della Ricca, G. Gobbo, B. and La Licata, C. Marone, M. Schizzi, A. Zanetti, A. and Kropivnitskaya, A. Nam, S. K. Kim, D. H. Kim, G. N. Kim, M. S. Kong, D. J. Lee, S. Oh, Y. D. Sakharov, A. and Son, D. C. Brochero Cifuentes, J. A. Kim, H. Kim, T. J. and Song, S. Choi, S. Go, Y. Gyun, D. Hong, B. Jo, M. and Kim, H. Kim, Y. Lee, B. Lee, K. Lee, K. S. Lee, S. Park, S. K. Roh, Y. Yoo, H. D. Choi, M. Kim, H. and Kim, J. H. Lee, J. S. H. Park, I. C. Ryu, G. Ryu, M. S. Choi, Y. Goh, J. Kim, D. Kwon, E. Lee, J. Yu, I. Dudenas, V. Juodagalvis, A. Vaitkus, J. Ahmed, I. and Ibrahim, Z. A. Komaragiri, J. R. Md Ali, M. A. B. Mohamad Idris, F. Wan Abdullah, W. A. T. Yusli, M. N. Casimiro Linares, E. Castilla-Valdez, H. De La Cruz-Burelo, E. and Heredia-De La Cruz, I. Hernandez-Almada, A. Lopez-Fernandez, R. and Sanchez-Hernandez, A. Carrillo Moreno, S. Valencia, F. Vazquez Pedraza, I. Salazar Ibarguen, H. A. Morelos Pineda, A. Krofcheck, D. Butler, P. H. Ahmad, A. Ahmad, M. and Hassan, Q. Hoorani, H. R. Khan, W. A. Khurshid, T. and Shoaib, M. Bialkowska, H. Bluj, M. Boimska, B. Frueboes, T. Gorski, M. Kazana, M. Nawrocki, K. and Romanowska-Rybinska, K. Szleper, M. Zalewski, P. Brona, G. and Bunkowski, K. Byszuk, A. Doroba, K. Kalinowski, A. and Konecki, M. Krolikowski, J. Misiura, M. Olszewski, M. and Walczak, M. Bargassa, P. Beirao Da Cruz E Silva, C. Di Francesco, A. Faccioli, P. Ferreira Parracho, P. G. and Gallinaro, M. Leonardo, N. Lloret Iglesias, L. Nguyen, F. and Rodrigues Antunes, J. Seixas, J. Toldaiev, O. Vadruccio, D. Varela, J. Vischia, P. Afanasiev, S. Bunin, P. and Gavrilenko, M. Golutvin, I. Gorbunov, I. Kamenev, A. and Karjavin, V. Konoplyanikov, V. Lanev, A. Malakhov, A. and Matveev, V. Moisenz, P. Palichik, V. Perelygin, V. and Shmatov, S. Shulha, S. Skatchkov, N. Smirnov, V. and Zarubin, A. Golovtsov, V. Ivanov, Y. Kim, V. Kuznetsova, E. Levchenko, P. Murzin, V. Oreshkin, V. Smirnov, I. and Sulimov, V. Uvarov, L. Vavilov, S. Vorobyev, A. Andreev, Yu. Dermenev, A. Gninenko, S. Golubev, N. Karneyeu, A. and Kirsanov, M. Krasnikov, N. Pashenkov, A. Tlisov, D. and Toropin, A. Epshteyn, V. Gavrilov, V. Lychkovskaya, N. and Popov, V. Pozdnyakov, I. Safronov, G. Spiridonov, A. and Vlasov, E. Zhokin, A. Bylinkin, A. Andreev, V. Azarkin, M. Dremin, I. Kirakosyan, M. Leonidov, A. Mesyats, G. and Rusakov, S. V. Baskakov, A. Belyaev, A. Boos, E. and Bunichev, V. Dubinin, M. Dudko, L. Ershov, A. Gribushin, A. Klyukhin, V. Korneeva, N. Lokhtin, I. Myagkov, I. and Obraztsov, S. Perfilov, M. Savrin, V. Azhgirey, I. and Bayshev, I. Bitioukov, S. Kachanov, V. Kalinin, A. and Konstantinov, D. Krychkine, V. Petrov, V. Ryutin, R. and Sobol, A. Tourtchanovitch, L. Troshin, S. Tyurin, N. and Uzunian, A. Volkov, A. Adzic, P. Milosevic, J. Rekovic, V. Alcaraz Maestre, J. Calvo, E. Cerrada, M. Chamizo Llatas, M. Colino, N. De La Cruz, B. Delgado Peris, A. and Dominguez Vazquez, D. Escalante Del Valle, A. Fernandez Bedoya, C. Fernandez Ramos, J. P. Flix, J. Fouz, M. C. and Garcia-Abia, P. Gonzalez Lopez, O. Goy Lopez, S. Hernandez, J. M. Josa, M. I. Navarro De Martino, E. Perez-Calero Yzquierdo, A. Puerta Pelayo, J. Quintario Olmeda, A. and Redondo, I. Romero, L. Santaolalla, J. Soares, M. S. and Albajar, C. de Trocniz, J. F. Missiroli, M. Moran, D. and Cuevas, J. Fernandez Menendez, J. Folgueras, S. Gonzalez Caballero, I. Palencia Cortezon, E. Vizan Garcia, J. M. and Cabrillo, I. J. Calderon, A. Castineiras De Saa, J. R. De Castro Manzano, P. Duarte Campderros, J. Fernandez, M. and Garcia-Ferrero, J. Gomez, G. Lopez Virto, A. Marco, J. and Marco, R. Martinez Rivero, C. Matorras, F. Munoz Sanchez, F. J. Piedra Gomez, J. Rodrigo, T. Rodriguez-Marrero, A. Y. and Ruiz-Jimeno, A. Scodellaro, L. Trevisani, N. Vila, I. and Vilar Cortabitarte, R. Abbaneo, D. Auffray, E. Auzinger, G. and Bachtis, M. Baillon, P. Ball, A. H. 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Salfeld-Nebgen, J. and Stephans, G. S. F. Sumorok, K. Varma, M. Velicanu, D. and Veverka, J. Wang, J. Wang, T. W. Wyslouch, B. Yang, M. Zhukova, V. Dahmes, B. Evans, A. Finkel, A. Gude, A. Hansen, P. Kalafut, S. Kao, S. C. Klapoetke, K. and Kubota, Y. Lesko, Z. Mans, J. Nourbakhsh, S. Ruckstuhl, N. Rusack, R. Tambe, N. Turkewitz, J. Acosta, J. G. and Oliveros, S. Avdeeva, E. Bloom, K. Bose, S. Claes, D. R. and Dominguez, A. Fangmeier, C. Gonzalez Suarez, R. and Kamalieddin, R. Keller, J. Knowlton, D. Kravchenko, I. and Meier, F. Monroy, J. Ratnikov, F. Siado, J. E. Snow, G. R. Alyari, M. Dolen, J. George, J. Godshalk, A. and Harrington, C. Iashvili, I. Kaisen, J. Kharchilava, A. and Kumar, A. Rappoccio, S. Roozbahani, B. Alverson, G. and Barberis, E. Baumgartel, D. Chasco, M. Hortiangtham, A. and Massironi, A. Morse, D. M. Nash, D. Orimoto, T. Teixeira De Lima, R. Trocino, D. Wang, R. -J. Wood, D. Zhang, J. and Hahn, K. A. Kubik, A. Mucia, N. Odell, N. Pollack, B. Pozdnyakov, A. Schmitt, M. Stoynev, S. Sung, K. and Trovato, M. Velasco, M. Brinkerhoff, A. Dev, N. and Hildreth, M. Jessop, C. Karmgard, D. J. Kellams, N. and Lannon, K. Lynch, S. Marinelli, N. Meng, F. Mueller, C. and Musienko, Y. Pearson, T. Planer, M. Reinsvold, A. and Ruchti, R. Smith, G. Taroni, S. Valls, N. Wayne, M. and Wolf, M. Woodard, A. Antonelli, L. Brinson, J. Bylsma, B. Durkin, L. S. Flowers, S. Hart, A. Hill, C. and Hughes, R. Ji, W. Kotov, K. Ling, T. Y. Liu, B. Luo, W. Puigh, D. Rodenburg, M. Winer, B. L. Wulsin, H. W. and Driga, O. Elmer, P. Hardenbrook, J. Hebda, P. Koay, S. A. Lujan, P. Marlow, D. Medvedeva, T. Mooney, M. and Olsen, J. Palmer, C. Piroue, P. Saka, H. Stickland, D. and Tully, C. Zuranski, A. Malik, S. Barnes, V. E. and Benedetti, D. Bortoletto, D. Gutay, L. Jha, M. K. Jones, M. Jung, K. Miller, D. H. Neumeister, N. Radburn-Smith, B. C. Shi, X. Shipsey, I. Silvers, D. Sun, J. and Svyatkovskiy, A. Wang, F. Xie, W. Xu, L. Parashar, N. and Stupak, J. Adair, A. 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Safonov, A. Tatarinov, A. Ulmer, K. A. and Akchurin, N. Cowden, C. Damgov, J. Dragoiu, C. Dudero, P. R. Faulkner, J. Kunori, S. Lamichhane, K. Lee, S. W. and Libeiro, T. Undleeb, S. Volobouev, I. Appelt, E. and Delannoy, A. G. Greene, S. Gurrola, A. Janjam, R. Johns, W. Maguire, C. Mao, Y. Melo, A. Ni, H. Sheldon, P. and Snook, B. Tuo, S. Velkovska, J. Xu, Q. Arenton, M. W. Cox, B. Francis, B. Goodell, J. Hirosky, R. and Ledovskoy, A. Li, H. Lin, C. Neu, C. Sinthuprasith, T. and Sun, X. Wang, Y. Wolfe, E. Wood, J. Xia, F. and Clarke, C. Harr, R. Karchin, P. E. Don, C. Kottachchi Kankanamge Lamichhane, P. Sturdy, J. Belknap, D. A. and Carlsmith, D. Cepeda, M. Dasu, S. Dodd, L. Duric, S. and Gomber, B. Grothe, M. Hall-Wilton, R. Herndon, M. Herve, A. Klabbers, P. Lanaro, A. Levine, A. Long, K. and Loveless, R. Mohapatra, A. Ojalvo, I. Perry, T. Pierro, G. A. Polese, G. Ruggles, T. Sarangi, T. Savin, A. and Sharma, A. Smith, N. Smith, W. H. Taylor, D. Woods, N. and CMS Collaboration

Subjects
High Energy Physics::Experiment
Abstract

A measurement of the top quark pair production () cross section in proton-proton collisions at the centre-of-mass energy of 8 is presented using data collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 19.6. This analysis is performed in the decay channels with one isolated, high transverse momentum electron or muon and at least four jets, at least one of which is required to be identified as originating from hadronization of a b quark. The calibration of the jet energy scale and the efficiency of b jet identification are determined from data. The measured cross section is . This measurement is compared with an analysis of 7 data, corresponding to an integrated luminosity of 5.0, to determine the ratio of 8 to 7 cross sections, which is found to be . The measurements are in agreement with QCD predictions up to next-to-next-to-leading order.

Published
2017

45. Extension of electron cyclotron heating at ASDEX Upgrade with respect to high density operation

Author

M. Schubert, W. Kasparek, S. Vorbrugg, Albrecht Herrmann, J. Stober, H. Zohm, D. Wagner, B. Petzold, F. Monaco, F. Leuterer, Burkhard Plaum, and ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society

Subjects
Physics, business.industry, QC1-999, Cyclotron, Electrical engineering, Pulse duration, Plasma, Electron, 7. Clean energy, 01 natural sciences, Electron cyclotron resonance, 010305 fluids & plasmas, law.invention, Optics, ASDEX Upgrade, law, 0103 physical sciences, Electromagnetic shielding, Heat shield, 010306 general physics, business
Abstract

The ASDEX Upgrade electron cyclotron resonance heating operates at 105 GHz and 140 GHz with flexible launching geometry and polarization. In 2016 four Gyrotrons with 10 sec pulse length and output power close to 1 MW per unit were available. The system is presently being extended to eight similar units in total. High heating power and high plasma density operation will be a part of the future ASDEX Upgrade experiment program. For the electron cyclotron resonance heating, an O-2 mode scheme is proposed, which is compatible with the expected high plasma densities. It may, however, suffer from incomplete single-pass absorption. The situation can be improved significantly by installing holographic mirrors on the inner column, which allow for a second pass of the unabsorbed fraction of the millimetre wave beam. Since the beam path in the plasma is subject to refraction, the beam position on the holographic mirror has to be controlled. Thermocouples built into the mirror surface are used for this purpose. As a protective measure, the tiles of the heat shield on the inner column were modified in order to increase the shielding against unabsorbed millimetre wave power.

Published
2017

46. Recent development of collective Thomson scattering for magnetically confined fusion plasmas

Author

Frank Leipold, J. Juul Rasmussen, S. K. Hansen, P. K. Michelsen, M. Schubert, J. Stober, D. Wagner, Søren Bang Korsholm, M. Stejner, Stefan Kragh Nielsen, Mirko Salewski, and ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society

Subjects
Physics, Collective Thomson scattering, Scattering, Thomson scattering, Fast ions, Plasma, Inelastic scattering, Condensed Matter Physics, 01 natural sciences, Atomic and Molecular Physics, and Optics, Charged particle, Plasma physics, Plasma diagnostics, 010305 fluids & plasmas, Ion, Nuclear physics, ASDEX Upgrade, Physics::Plasma Physics, 0103 physical sciences, 010306 general physics, CTS, Mathematical Physics
Abstract

Here we review recent experimental developments within the field of collective Thomson scattering with a focus on the progress made on the devices TEXTOR and ASDEX Upgrade. We discuss recently discovered possibilities and limitations of the diagnostic technique. Diagnostic applications with respect to ion measurements are demonstrated. Examples include measurements of the ion temperature, energetic ion distribution function, and the ion composition.

Published
2017
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47. Active control of Alfvén eigenmodes in magnetically confined toroidal plasmas

Author

E. Ascasíbar, J. Gonzalez-Martin, Jorge Ferreira, F. Nabais, P. Vallejos, J. Galdon-Quiroga, J. F. Rivero-Rodriguez, M. J. Mantsinen, P. A. Schneider, M. Garcia-Munoz, S. E. Sharapov, A. Cappa, Ph. Lauber, A.V. Melnikov, J. Stober, William Heidbrink, W. Suttrop, L. Sanchis-Sanchez, Fulvio Zonca, Yasushi Todo, Thomas Johnson, M. A. Van Zeeland, Ling Chen, Benedikt Geiger, Mst Teams, Garcia-Munoz, M., Sharapov, S. E., Van Zeeland, M. A., Ascasibar, E., Cappa, A., Chen, L., Ferreira, J., Galdon-Quiroga, J., Geiger, B., Gonzalez-Martin, J., Heidbrink, W. W., Johnson, T., Lauber, P., Mantsinen, M., Melnikov, A. V., Nabais, F., Rivero-Rodriguez, J. F., Sanchis-Sanchez, L., Schneider, P., Stober, J., Suttrop, W., Todo, Y., Vallejos, P., Zonca, F., Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear, Universidad de Sevilla. RNM138: Física Nuclear Aplicada, Universidad de Sevilla. TEP111: Ingeniería Mecánica, ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society, MST1 Team, and Barcelona Supercomputing Center

Subjects
fusion, Tokamak, MHD, perturbation, Perturbation (astronomy), Perturbations, 01 natural sciences, 010305 fluids & plasmas, law.invention, stellarator, perturbations, Physics::Plasma Physics, law, 0103 physical sciences, Magnetohydrodynamic waves, waves, Fusion, 010306 general physics, tokamak, Computer Science::Databases, Stellarator, Ones electromagnètiques, Physics, Toroid, Electromagnetic waves, Física [Àrees temàtiques de la UPC], Stellarators, Plasma, Neutral beams, Condensed Matter Physics, Active control, Alfvén, Perturbation, Nuclear Energy and Engineering, Quantum electrodynamics, Physics::Space Physics, Waves, Magnetohydrodynamics, Tokamaks
Abstract

Alfvén waves are electromagnetic perturbations inherent to magnetized plasmas that can be driven unstable by a free energy associated with gradients in the energetic particles' distribution function. The energetic particles with velocities comparable to the Alfvén velocity may excite Alfvén instabilities via resonant wave–particle energy and momentum exchange. Burning plasmas with large population of fusion born super-Alfvénic alpha particles in magnetically confined fusion devices are prone to excite weakly-damped Alfvén eigenmodes (AEs) that, if allowed to grow unabated, can cause a degradation of fusion performance and loss of energetic ions through a secular radial transport. In order to control the fast-ion distribution and associated Alfvénic activity, the fusion community is currently searching for external actuators that can control AEs and energetic ions in the harsh environment of a fusion reactor. Most promising control techniques are based on (i) variable fast-ion sources to modify gradients in the energetic particles' distribution, (ii) localized electron cyclotron resonance heating to affect the fast-ion slowing-down distribution, (iii) localized electron cyclotron current drive to modify the equilibrium magnetic helicity and thus the AE existence criteria and damping mechanisms, and (iv) externally applied 3D perturbative fields to manipulate the fast-ion distribution and thus the wave drive. Advanced simulations help to identify the key physics mechanisms underlying the observed AE mitigation and suppression and thus to develop robust control techniques towards future burning plasmas. This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014–2018 and 2019–2020 under grant agreement No 633053. The views and opinions expressed herein do not necessarily reflect those of the European Commission. Support by US DOE and ITER-CN is also acknowledged. The support from the FP7 People: Marie-Curie Actions (Grant No. 321455) and the Spanish Ministry of Economy and Competitiveness (Grants No. RYC-2011-09152, No. FIS2015-69362-P) is gratefully acknowledged. The work of AVM was funded by the Russian Science Foundation, project 14-22-00193, and was partly supported by the Competitiveness Program of NRNU MEPhI.

Published
2019

48. Simulation of Polarising and Reflector Gratings for High Power mm Waves

Author

M. Schubert, Carsten Lechte, F. Leuterer, Burkhard Plaum, W. Kasparek, J. Stober, and D. Wagner

Subjects
Materials science, business.industry, Physics, QC1-999, Reflector (antenna), Polarizer, Grating, Electron cyclotron resonance, law.invention, Optics, ASDEX Upgrade, law, Harmonics, Reflection (physics), business, Waveguide
Abstract

High power mm waves for fusion plasma heating need to be elliptically polarised to ensure good absorption in the plasma. In some scenarios, electron cyclotron resonance heating (ECRH) at higher harmonics (X3 and O2) is used, but this has significant shine-through because of low single pass absorption. Grating reflectors at the inboard strike point form a holographic mirror that reflects the beam back into the plasma. This paper investigates the optical properties and ohmic losses of both the polariser and the reflectors with the 3D fullwave code IPF-FD3D. The reflection properties of a reflector for ASDEX Upgrade and the improved ohmic losses of a waveguide polariser were confirmed.

Published
2019

49. Development of reflection gratings for advanced ECRH scenarios

Author

M. Schubert, Burkhard Plaum, W. Kasparek, J. Stober, Achim Zeitler, C. Lechte, and ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society

Subjects
Physics, Series (mathematics), 010308 nuclear & particles physics, business.industry, QC1-999, Plane wave, Physics::Optics, Grating, 01 natural sciences, Optics, 0103 physical sciences, Incident beam, Reflection (physics), Physics::Accelerator Physics, Development (differential geometry), 010306 general physics, business, Beam (structure), Interpolation
Abstract

An existing framework for the design of reflection gratings was reworked. It takes the astigmatic complex beam parameters and the orientations of the beam axes of the incident and reflected beams as input and synthesizes a grating, which transforms the incident beam into the reflected beam. This is done by decomposing the 3D problem into a series of 2D reflections of plane waves. The 2D grating profiles are optimized in parallel on multiple computers. Finally, the 3D grating is derived using a simplified interpolation scheme.

Published
2019

50. Investigation of a broadband double-disc diamond window unit

Author

Andreas Meier, J. Stober, D. Wagner, Alessandro Vaccaro, and T.A. Scherer

Subjects
Tokamak, Materials science, business.industry, Terahertz radiation, Phase (waves), Window (computing), Diamond, engineering.material, Interference (wave propagation), 01 natural sciences, 010305 fluids & plasmas, law.invention, Optics, ASDEX Upgrade, law, 0103 physical sciences, engineering, Brazing, 010306 general physics, business
Abstract

In this paper we investigate the potential causes of failure of a diamond window unit employed in the experimental tokamak ASDEX Upgrade in Garching, Germany. The window unit features a double-disc configuration that allows for a more complex transmission spectrum than with a single disc and is used in conjunction with step-tunable gyrotrons for electron-cyclotron heating of fusion plasmas. The window unit failed during high-power operation as a consequence of a crack in one of the two diamond discs. The event that initiated the crack is unknown. Two possible reasons have been investigated in detail: high stress on the diamond due to bad quality of the brazing and due to localized power depositions. The first is investigated by computer tomography imaging of the brazing, the second by means of a custom ray-tracing code that uses a “hybrid” approach that accounts for the waves' phase, thus reproducing the effects of interference.

Published
2016

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