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151. Feedback control of the sawtooth period through real time control of the ion cyclotron resonance frequency

Author: G. Calabrò, R. J. Dumont, M.-L. Mayoral, S. Jachmich, M. Lennholm, Carlo Sozzi, M. Tsalas, M. E. Graham, Jet-Efda Contributors, P. de Vries, M.F. Stamp, I. T. Chapman, M.R. de Baar, L.-G. Eriksson, T. R. Blackman, D. F. Howell, and Jonathan Graves
Subjects: Physics, Nuclear and High Energy Physics, Jet (fluid), Period (periodic table), Flux, Sawtooth wave, Condensed Matter Physics, Computational physics, sawtooth control realtime, Control theory, Real-time Control System, Absorption (electromagnetic radiation), Ion cyclotron resonance
Abstract: Modification of the sawtooth period through ion cyclotron resonance frequency (ICRF) heating and current drive has been demonstrated in a number of experiments. The effect has been seen to depend critically on the location of the ICRF absorption region with respect to the q = 1 flux surface. Consequently, for ICRF to be a viable tool for sawtooth control, one must be able to control the ICRF absorption location in real time so as to follow variations in the location of the q = 1 surface. To achieve this, the JET ICRF system has been modified to allow the JET real time central controller to control the frequency of the ICRF generators. An algorithm for real time determination of the sawtooth period has been developed and a closed loop controller, which modifies the frequency of the ICRF generators to bring the measured sawtooth period to the desired reference value, has been implemented. This paper shows the first experimental demonstration of closed loop sawtooth period control by real time variation of the ICRF wave frequency.
Published: 2011
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152. Lower hybrid current drive for the steady-state scenario

Author: G. T. Hoang, K. K. Kirov, Yves Peysson, D. Dodt, Gregory Wallace, A. Ekedahl, C. Castaldo, Julien Hillairet, J. Garcia, Pankaj Sharma, Lorenzo Figini, G. Calabrò, X. Litaudon, T. Oosako, A. E. Hubbard, P. Platania, G. Giruzzi, V. Pericoli Ridolfini, Yu.F. Baranov, F.G. Rimini, R. Cesario, E. Joffrin, A. Cardinali, R. Parker, L. Amicucci, J. Mailloux, J. Decker, Carlo Sozzi, M. Goniche, and V. Basiuk
Subjects: Physics, Jet (fluid), WAVES, Cyclotron, Bremsstrahlung, Electron, Plasma, Tore Supra, Condensed Matter Physics, Electromagnetic radiation, law.invention, TOKAMAK PLASMAS, Nuclear Energy and Engineering, JET, Physics::Plasma Physics, law, SIMPLE-MODEL, PARAMETRIC-INSTABILITIES, Emission spectrum, Atomic physics
Abstract: Lower hybrid current drive (LHCD) experiments performed at a density close to that required for the steady-state (SS) scenario are reported. On C-Mod, FTU and Tore Supra, a strong decay of the bremsstrahlung emission is observed when the density is increased, much faster that the prediction of LHCD modelling. On JET, LH power deposition is also found to be sensitive to the plasma density: LH power modulation indicates that the power deposition moves to the very edge of the plasma (r/a similar to 0.9) when the density approaches the requirement of the JET SS scenario. From this experiment but also from the reconstruction of the electron cyclotron emission spectrum, the decrease in the LHCD efficiency with density is also found. From LHCD modelling of different JET pulses performed at different densities and wave parallel refraction indexes, it is concluded that the wave accessibility condition is not the key parameter for explaining the decrease in the efficiency. C-Mod, FTU and Tore Supra experiments indicate that the plasma edge parameters, namely density and temperature but also fluctuations, are affecting the efficiency via loss mechanisms which are likely to be collisional damping (C-Mod), parametric decay instabilities or wave scattering (FTU/Tore Supra).
Published: 2010
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153. Stationary magnetic entropy tokamak states and experimental observations

Author: E. Minardi, P. Mantica, Jet-Efda Contributors, and Carlo Sozzi
Subjects: Physics, Nuclear and High Energy Physics, Tokamak, Normal conditions, Condensed matter physics, business.industry, Mechanics, Plasma, Condensed Matter Physics, law.invention, Physics::Plasma Physics, law, ____, Entropy (energy dispersal), business, Current density, Thermal energy
Abstract: The assumption that the tokamak magnetic configuration at equilibrium is associated with the stationary magnetic entropy and with minimum plasma thermal energy leads to the prediction of definite profiles for the induced current density and for the pressure. These profiles should characterize the states spontaneously assumed by the tokamak under normal conditions (to be defined in the text).The theoretical results are compared with the observations collected from different tokamaks, plasma regimes and heating methods, taking into account the possible existence of non-inductive currents. The comparison allows the identification of the limits of validity of the model and confirms the robustness, within these limits, of the magnetic entropy concept for the description of the ‘privileged’ tokamak states.
Published: 2008
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154. Analysis of metallic impurity density profiles in low collisionality Joint European Torus H-mode and L-mode plasmas

Author: M. Mattioli, P. Mantica, I. H. Coffey, M. E. Puiatti, M. Valisa, C. Angioni, Jet-Efda Contributors, Carlo Sozzi, L. Garzotti, and L. Carraro
Subjects: Physics, plasma density, Magnetically Confined Plasmas, Thermonuclear fusion, Tokamak devices, Joint European Torus, chemistry.chemical_element, Plasma, Collisionality, Condensed Matter Physics, plasma toroidal confinement, Ion, Heating, nickel, Nickel, chemistry, Physics::Plasma Physics, Pinch, Electron temperature, Atomic physics, plasma impurities, Confinement
Abstract: This paper describes the behavior of nickel in low confinement (L-mode) and high confinement (H-mode) Joint European Torus (JET) discharges [P. J. Lomas, Plasma Phys. Control. Fusion 31, 1481 (1989)] characterized by the application of radio-frequency (rf) power heating and featuring ITER (International Thermonuclear Experimental Reactor) relevant collisionality. The impurity transport is analyzed on the basis of perturbative experiments (laser blow off injection) and is compared with electron heat and deuterium transport. In the JET plasmas analyzed here, ion cyclotron resonance heating (ICRH) is applied either in mode conversion (MC) to heat the electrons or in minority heating (MH) to heat the ions. The two heating schemes have systematically different effects on nickel transport, yielding flat or slightly hollow nickel density profiles in the case of ICRH in MC and peaked nickel density profiles in the case of rf applied in MH. Accordingly, both diffusion coefficients and pinch velocities of nickel are found to be systematically different. Linear gyrokinetic calculations by means of the code GS2 [M. Kotschenreuther, G. Rewoldt, and W.M. Tang, Comput. Phys. Commun. 88, 128 (1995)] provide a possible explanation of such different behavior by exploring the effects produced by the different microinstabilities present in these plasmas. In particular, trapped electron modes driven by the stronger electron temperature gradients measured in the MC cases, although subdominant, produce a contribution to the impurity pinch directed outwards that is qualitatively in agreement with the pinch reversal found in the experiment. Particle and heat diffusivities appear to be decoupled in MH shots, with ?e and DD>>DNi, and are instead quite similar in the MC ones. In the latter case, nickel transport appears to be driven by the same turbulence that drives the electron heat transport and is sensitive to the value of the electron temperature gradient length. These findings give ground to the idea that in ITER it should be possible to find conditions in which the risk of accumulation of metals such as nickel can be contained
Published: 2006
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155. Electric Birefringence of a Dispersion of Electrically Charged Anisotropic Particles

Author: Roberto Piazza, Tommaso Bellini, Vittorio Degiorgio, and Carlo Sozzi
Subjects: chemistry.chemical_classification, Materials science, Birefringence, Condensed matter physics, business.industry, General Physics and Astronomy, Rotational diffusion, Square wave, Rod, Condensed Matter::Soft Condensed Matter, Optics, chemistry, Electric field, Volume fraction, Dispersion (optics), sense organs, Counterion, business
Abstract: We have measured the static and dynamic birefringence induced by an electric field on a dispersion of PTFE rods having length of about 0.33 ?m and diameter of 0.15 ?m. The rods are electrically charged and have a crystalline structure. By using a pulse consisting of a train of square waves of variable frequency, we have been able to separate the contribution of the counterion cloud from that due only to form and intrinsic anisotropy of the rods. We find that the optical anisotropy of the material is n|| - n??=?0.04. At volume fractions above 0.1% we find an important collective effect in the measured Kerr constant. Such an effect disappears upon addition of a few mM NaCl. The dynamics of electric birefringence appears to be controlled by the rotational diffusion constant of the individual rod, irrespective of the volume fraction and the added salt concentration.
Published: 1988
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156. Tracking of neoclassical tearing modes in TCV using the electron cyclotron emission diagnostics in quasi-in-line configuration

Author: M. Fontana, D. Micheletti, A. Moro, U. A. Sheikh, E. Alessi, Saul Garavaglia, Stefano Coda, M. Maraschek, M. Kong, N. Rispoli, Laurie Porte, Carlo Sozzi, Timothy Goodman, Duccio Testa, Lorenzo Figini, Cristian Galperti, Olivier Sauter, EUROfusion MST1 Team, and TCV Team
Subjects: Physics, Tokamak, Toroid, 010308 nuclear & particles physics, Mechanical Engineering, Cyclotron, Plasma, Electron, Real time control, Tracking (particle physics), 01 natural sciences, 010305 fluids & plasmas, law.invention, Computational physics, Amplitude, Nuclear Energy and Engineering, law, Physics::Plasma Physics, 0103 physical sciences, General Materials Science, TCV, Magnetohydrodynamics, Neoclassical tearing mode, Civil and Structural Engineering
Abstract: An important goal of the control system in a tokamak is the suppression of magneto-hydrodynamic (MHD) instabilities with low m, n (poloidal and toroidal mode numbers), which can influence the confinement time of energy and particles and possibly lead to plasma disruption. These instabilities, which appear as rotating magnetic islands, can be reduced or completely suppressed by a current driven by electron cyclotron waves (ECW) accurately located within the island. A fundamental requisite for this control technique is the ability to identify the island parameters (amplitude and radial position) and to vary accordingly the ECW deposition location. Here we describe a control scheme of the steering mirror of the ECW source based on the real-time tracking of the island radial position realized using only the electron cyclotron emission (ECE) diagnostics in quasi-in-line configuration, i.e. with toroidal anti-parallel propagation of the ECW and ECE beams. The successful experimental proof of principle of this scheme, tested on the TCV tokamak, is here reported.
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157. Overview of the TCV tokamak program: scientific progress and facility upgrades

Author: S. Mastrostefano, J.-Ph. Hogge, S. Nowak, W. Bin, Bogdan Hnat, Nuno Cruz, S. Allan, T. C. Blanken, Cristian Galperti, H. F. Meyer, M. Faitsch, Stefano Coda, Y. Andrebe, D. Rittich, E. Maljaars, Laust Emil Hjerrild Tophøj, C. Ham, P. Molina Cabrera, Alessandro Pau, Jonathan Graves, D. Douai, C.K. Tsui, H. Weisen, J-M Moret, Marco Gobbin, M. Nocente, David Moulton, Heinz Isliker, F. Sciortino, S. Vartanian, M. Koubiti, P. A. Schneider, V. P. Loschiavo, R. M. McDermott, E. Alessi, I Miron, Yann Camenen, F. Braunmüller, Duccio Testa, T. Odstrcil, J. Juul Rasmussen, J. Horacek, M. Sertoli, G. De Tommasi, Geert Verdoolaege, Patrick Maget, Gustavo Granucci, Timothy P. Robinson, M. Preynas, Cyrille Honoré, Benedikt Geiger, Paolo Innocente, C. Tsironis, A. Jardin, J.A. Boedo, Izaskun Garrido, M. Gospodarczyk, M. G. Dunne, F. Carpanese, M. Kong, Ondrej Ficker, N. Vianello, V. Igochine, P. Zestanakis, V. Pericoli Ridolfini, R. Scannell, T. Lunt, A. Malygin, J. Ahn, M. Bernert, G. Calabrò, Theophilos Pisokas, M. Wischmeier, Piero Martin, Fulvio Militello, B. Lomanowski, Benoit Labit, Giuseppe Gorini, Daniele Carnevale, A. Czarnecka, Faa Federico Felici, F. Saint-Laurent, B. Sieglin, X. Llobet, Patrick Tamain, M. Mavridis, G. Ciraolo, Ambrogio Fasoli, J. Sinha, F. Causa, Ch. Schlatter, J. Decker, Raffaele Albanese, P. Blanchard, F. Bouquey, C. Angioni, G. De Masi, R. McAdams, A. Moro, S. Garavaglia, Hugo Bufferand, Antoine Merle, O. Chellai, Torsten Stange, Laure Vermare, Loukas Vlahos, W. A. J. Vijvers, G. Pautasso, Olivier Février, N. A. Kirneva, H. Reimerdes, Timothy Goodman, Nicolas Fedorczak, Bruce Lipschultz, E. Lazzaro, C. Piron, Z. Huang, J. Kamleitner, James Harrison, Fabio Riva, Lorenzo Frassinetti, Paolo Ricci, Y. R. Martin, Anders Nielsen, B. Esposito, Jonathan Citrin, Antti Hakola, M. Reich, I. T. Chapman, Kevin Verhaegh, C. Marini, H.B. Le, V. Naulin, B. P. Duval, M. Silva, A. Gallo, J. Hawke, A. Krämer-Flecken, D. Hogeweij, N. Krawczyk, Roberto Maurizio, Ivo Furno, Marco Ariola, Christian Theiler, A. N. Karpushov, Jernej Kovacic, M. N. A. Beurskens, A. Uccello, M. Fontana, C. J. Rapson, Tom Wauters, Christian Hopf, C. Ionita Schrittwieser, S. Saarelma, T. Eich, T. Stoltzfus-Dueck, S. Fietz, P. Piovesan, R. Jacquier, D. Choi, H. Anand, Nick Walkden, Gergely Papp, F. Nespoli, D. L. Keeling, B. S. Schneider, Sergio Galeani, G. Ramogida, S. Elmore, E. Giovannozzi, Stefano Alberti, Rémy Nouailletas, O. Kudlacek, R. Guirlet, R. Papřok, Matteo Zuin, T. Bolzonella, F. Crisanti, D. Mazon, U. A. Sheikh, Pascale Hennequin, R. Cesario, A.J. Thornton, S. Costea, P. Buratti, C. Cianfarani, R. Schrittwieser, A. Teplukhina, N.M.T. Vu, Laurie Porte, M. Spolaore, Carlo Sozzi, Minh Quang Tran, M. Maraschek, Olivier Sauter, C. Reux, G. Anastassiou, Ramogida, G., Giovannozzi, E., Esposito, B., Cianfarani, C., Cesario, R., Causa, F., Calabró, G., Buratti, P., Max-Planck-Institut für Plasmaphysik [Garching] (IPP), EURATOM/CCFE Fusion Association, Culham Science Centre [Abingdon], Institut de Recherche sur la Fusion par confinement Magnétique (IRFM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Physique des interactions ioniques et moléculaires (PIIM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences et Ingénierie Chimiques (ISIC), Ecole Polytechnique Fédérale de Lausanne (EPFL), Associazone EURATOM ENEA sulla Fusione, EURATOM, Sygen International Plc, Laboratoire de Physique des Plasmas (LPP), Université Paris-Sud - Paris 11 (UP11)-Université Pierre et Marie Curie - Paris 6 (UPMC)-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), Institute of Plasma Physics, Association Euratom/IPP.CR (IPP PRAGUE), Czech Academy of Sciences [Prague] (CAS), York Plasma Institute (YPI), University of York [York, UK], Association EURATOM-CEA (CEA/DSM/DRFC), Association EURATOM-Risø National Laboratory, Technical University of Denmark [Lyngby] (DTU), Plateforme RX, UFR Chimie, Université Paris Diderot - Paris 7 (UPD7), Istituto di Fisica del Plasma, EURATOM-ENEA-CNR Association, Consiglio Nazionale delle Ricerche [Roma] (CNR), EUROfusion MST1 Team, Coda, S., Ahn, J., Albanese, Raffaele, Alberti, S., Alessi, E., Allan, S., Anand, H., Anastassiou, G., Andrèbe, Y., Angioni, C., Ariola, M., Bernert, M., Beurskens, M., Bin, W., Blanchard, P., Blanken, T. C., Boedo, J. A., Bolzonella, T., Bouquey, F., Braunmüller, F. H., Bufferand, H., Camenen, Y., Carnevale, D., Carpanese, F., Chapman, I. T., Chellai, O., Choi, D., Ciraolo, G., Citrin, J., Costea, S., Crisanti, F., Cruz, N., Czarnecka, A., Decker, J., De Masi, G., DE TOMMASI, Gianmaria, Douai, D., Dunne, M., Duval, B. P., Eich, T., Elmore, S., Faitsch, M., Fasoli, A., Fedorczak, N., Felici, F., Février, O., Ficker, O., Fietz, S., Fontana, M., Frassinetti, L., Furno, I., Galeani, S., Gallo, A., Galperti, C., Garavaglia, S., Garrido, I., Geiger, B., Gobbin, M., Goodman, T. P., Gorini, G., Gospodarczyk, M., Granucci, G., Graves, J. P., Guirlet, R., Hakola, A., Ham, C., Harrison, J., Hawke, J., Hennequin, P., Hnat, B., Hogeweij, D., Hogge, J. P. h., Honoré, C., Hopf, C., Horáček, J., Huang, Z., Igochine, V., Innocente, P., Ionita Schrittwieser, C., Isliker, H., Jacquier, R., Jardin, A., Kamleitner, J., Karpushov, A., Keeling, D. L., Kirneva, N., Kong, M., Koubiti, M., Kovacic, J., Krämer Flecken, A., Krawczyk, N., Kudlacek, O., Labit, B., Lazzaro, E., Le, H. B., Lipschultz, B., Llobet, X., Lomanowski, B., Loschiavo, VINCENZO PAOLO, Lunt, T., Maget, P., Maljaars, E., Malygin, A., Maraschek, M., Marini, C., Martin, P., Martin, Y., Mastrostefano, S., Maurizio, R., Mavridis, M., Mazon, D., Mcadams, R., Mcdermott, R., Merle, A., Meyer, H., Militello, F., Miron, I. G., Molina Cabrera, P. A., Moret, J. M., Moro, A., Moulton, D., Naulin, V., Nespoli, F., Nielsen, A. H., Nocente, M., Nouailletas, R., Nowak, S., Odstrčil, T., Papp, G., Papřok, R., Pau, A., Pautasso, G., Pericoli Ridolfini, V., Piovesan, P., Piron, C., Pisokas, T., Porte, L., Preynas, M., Rapson, C., Juul Rasmussen, J., Reich, M., Reimerdes, H., Reux, C., Ricci, P., Rittich, D., Riva, F., Robinson, T., Saarelma, S., Saint Laurent, F., Sauter, O., Scannell, R., Schlatter, C. h., Schneider, B., Schneider, P., Schrittwieser, R., Sciortino, F., Sertoli, M., Sheikh, U., Sieglin, B., Silva, M., Sinha, J., Sozzi, C., Spolaore, M., Stange, T., Stoltzfus Dueck, T., Tamain, P., Teplukhina, A., Testa, D., Theiler, C., Thornton, A., Tophøj, L., Tran, M. Q., Tsironis, C., Tsui, C., Uccello, A., Vartanian, S., Verdoolaege, G., Verhaegh, K., Vermare, L., Vianello, N., Vijvers, W. A. J., Vlahos, L., Vu, N. M. T., Walkden, N., Wauters, T., Weisen, H., Wischmeier, M., Zestanakis, P., Zuin, M., Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École polytechnique (X)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Danmarks Tekniske Universitet = Technical University of Denmark (DTU), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Coda, S, Ahn, J, Albanese, R, Alberti, S, Alessi, E, Allan, S, Anand, H, Anastassiou, G, Andrãbe, Y, Angioni, C, Ariola, M, Bernert, M, Beurskens, M, Bin, W, Blanchard, P, Blanken, T, Boedo, J, Bolzonella, T, Bouquey, F, Braunmã¼ller, F, Bufferand, H, Buratti, P, Calabrã³, G, Camenen, Y, Carnevale, D, Carpanese, F, Causa, F, Cesario, R, Chapman, I, Chellai, O, Choi, D, Cianfarani, C, Ciraolo, G, Citrin, J, Costea, S, Crisanti, F, Cruz, N, Czarnecka, A, Decker, J, De Masi, G, De Tommasi, G, Douai, D, Dunne, M, Duval, B, Eich, T, Elmore, S, Esposito, B, Faitsch, M, Fasoli, A, Fedorczak, N, Felici, F, Fã©vrier, O, Ficker, O, Fietz, S, Fontana, M, Frassinetti, L, Furno, I, Galeani, S, Gallo, A, Galperti, C, Garavaglia, S, Garrido, I, Geiger, B, Giovannozzi, E, Gobbin, M, Goodman, T, Gorini, G, Gospodarczyk, M, Granucci, G, Graves, J, Guirlet, R, Hakola, A, Ham, C, Harrison, J, Hawke, J, Hennequin, P, Hnat, B, Hogeweij, D, Hogge, J, Honorã©, C, Hopf, C, Horã¡ä ek, J, Huang, Z, Igochine, V, Innocente, P, Ionita Schrittwieser, C, Isliker, H, Jacquier, R, Jardin, A, Kamleitner, J, Karpushov, A, Keeling, D, Kirneva, N, Kong, M, Koubiti, M, Kovacic, J, KrÃ¤mer-Flecken, A, Krawczyk, N, Kudlacek, O, Labit, B, Lazzaro, E, Le, H, Lipschultz, B, Llobet, X, Lomanowski, B, Loschiavo, V, Lunt, T, Maget, P, Maljaars, E, Malygin, A, Maraschek, M, Marini, C, Martin, P, Martin, Y, Mastrostefano, S, Maurizio, R, Mavridis, M, Mazon, D, Mcadams, R, Mcdermott, R, Merle, A, Meyer, H, Militello, F, Miron, I, Molina Cabrera, P, Moret, J, Moro, A, Moulton, D, Naulin, V, Nespoli, F, Nielsen, A, Nocente, M, Nouailletas, R, Nowak, S, Odsträ il, T, Papp, G, PapÅ™ok, R, Pau, A, Pautasso, G, Pericoli Ridolfini, V, Piovesan, P, Piron, C, Pisokas, T, Porte, L, Preynas, M, Ramogida, G, Rapson, C, Juul Rasmussen, J, Reich, M, Reimerdes, H, Reux, C, Ricci, P, Rittich, D, Riva, F, Robinson, T, Saarelma, S, Saint-Laurent, F, Sauter, O, Scannell, R, Schlatter, C, Schneider, B, Schneider, P, Schrittwieser, R, Sciortino, F, Sertoli, M, Sheikh, U, Sieglin, B, Silva, M, Sinha, J, Sozzi, C, Spolaore, M, Stange, T, Stoltzfus-Dueck, T, Tamain, P, Teplukhina, A, Testa, D, Theiler, C, Thornton, A, Tophã¸j, L, Tran, M, Tsironis, C, Tsui, C, Uccello, A, Vartanian, S, Verdoolaege, G, Verhaegh, K, Vermare, L, Vianello, N, Vijvers, W, Vlahos, L, Vu, N, Walkden, N, Wauters, T, Weisen, H, Wischmeier, M, Zestanakis, P, and Zuin, M
Subjects: Nuclear and High Energy Physics, Tokamak, Technology and Engineering, Nuclear engineering, Overview, overview, 01 natural sciences, 010305 fluids & plasmas, law.invention, Settore ING-INF/04 - Automatica, law, Control theory, [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], 0103 physical sciences, 010306 general physics, tokamak, Nuclear and High Energy Physic, Physics, Toroid, Divertor, Magnetic confinement fusion, Plasma, Condensed Matter Physics, TCV, TRANSPORT, Magnetohydrodynamics, Beam (structure)
Abstract: a quiescent runaway beam carrying the entire electrical current appears to develop in some cases. Developments in plasma control have benefited from progress in individual controller design and have evolved steadily towards controller integration, mostly within an environment supervised by a tokamak profile control simulator. TCV has demonstrated effective wall conditioning with ECRH in He in support of the preparations for JT-60SA operation. © 2017 Ecole Polytechnique Federale de Lausanne., in particular, the double decay length in L-mode limited plasmas was found to be replaced by a single length at high SOL resistivity. Experiments on disruption mitigation by massive gas injection and electron-cyclotron resonance heating (ECRH) have begun in earnest, in parallel with studies of runaway electron generation and control, in both stable and disruptive conditions, The TCV tokamak is augmenting its unique historical capabilities (strong shaping, strong electron heating) with ion heating, additional electron heating compatible with high densities, and variable divertor geometry, in a multifaceted upgrade program designed to broaden its operational range without sacrificing its fundamental flexibility. The TCV program is rooted in a three-pronged approach aimed at ITER support, explorations towards DEMO, and fundamental research. A 1 MW, tangential neutral beam injector (NBI) was recently installed and promptly extended the TCV parameter range, with record ion temperatures and toroidal rotation velocities and measurable neutral-beam current drive. ITER-relevant scenario development has received particular attention, with strategies aimed at maximizing performance through optimized discharge trajectories to avoid MHD instabilities, such as peeling-ballooning and neoclassical tearing modes. Experiments on exhaust physics have focused particularly on detachment, a necessary step to a DEMO reactor, in a comprehensive set of conventional and advanced divertor concepts. The specific theoretical prediction of an enhanced radiation region between the two X-points in the low-field-side snowflake-minus configuration was experimentally confirmed. Fundamental investigations of the power decay length in the scrape-off layer (SOL) are progressing rapidly, again in widely varying configurations and in both D and He plasmas
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158. Enhanced confinement regimes with strong electron heating in the presence of flat or inverted safety factor profiles

Author: E. Barbato, M.L. Apicella, B. Tilia, M. Leigheb, G. Apruzzese, E. Giovannozzi, L Gabellieri, N. Tartoni, L Bertalot, D. Frigione, P. Buratti, M Panella, G. Maffia, B. Angelini, C. Centioli, F. Gravanti, H. Kroegler, Alessandro Simonetto, Carlo Sozzi, M. Marinucci, L. Panaccione, F. Santini, F. P. Orsitto, V Cocilovo, R. De Angelis, A. Bertocchi, V. Pericoli-Ridolfini, F. Crisanti, Fulvio Zonca, C. Gourlan, S. Ciattaglia, C. Cianfarani, R. Cesario, F. Alladio, B. C. Gregory, Francesco Mirizzi, Angelo A. Tuccillo, Gregorio Vlad, Alessandro Bruschi, M. Sassi, M R Belforte, P. Chuilon, C. Castaldo, B Esposito, G. Maddaluno, F. Iannone, M. Borra, G. Buceti, Francesco Romanelli, A. Cardinali, L. Pieroni, O. Tudisco, D. Pacella, G. Bracco, S. Podda, M. Grolli, G.B. Righetti, Gustavo Granucci, M. Zerbini, S. E. Segre, G. Mazzitelli, S Cirant, F. De Marco, E. Sternini, V Vitale, G Gatti, P Micozzi, and V Zanza
Subjects: Materials science, Safety factor, Tokamak, Frascati Tokamak Upgrade, Condensed Matter Physics, equipment and supplies, Electron transport chain, Settore FIS/07 - Fisica Applicata(Beni Culturali, Ambientali, Biol.e Medicin), Electron cyclotron resonance, law.invention, Shear (sheet metal), Nuclear Energy and Engineering, ___, law, Physics::Plasma Physics, Magnetohydrodynamic drive, Atomic physics, Magnetohydrodynamics, human activities
Abstract: The role of magnetic shear in affecting electron transport is discussed on the basis of the Frascati tokamak upgrade (FTU) data with central electron cyclotron resonance heating (ECRH) on the current ramp phase and with pellet injection. The results point out that strongly negative magnetic shear is not a necessary condition in order to have good electron transport and that magnetohydrodynamic (MHD) activity plays a crucial role in affecting the electron transport in the region with low/negative magnetic shear. The theoretical arguments for the dependence of transport on magnetic shear are reviewed and compared with the experimental evidence.
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159. Progress of CW and short-pulse calorimetric loads for high power millimeter-wave beams

Author: S. Cirant, A. Nardone, Gustavo Granucci, F. Gandini, N. Spinicchia, V. Mellera, V. Muzzini, William Bin, Carlo Sozzi, and Alessandro Bruschi
Subjects: Physics, business.industry, Terahertz radiation, Bolometer, law.invention, Pulse (physics), Wavelength, Optics, law, Extremely high frequency, Millimeter, business, Absorption (electromagnetic radiation), Electron gun
Abstract: A family of compact matched loads for high power millimeter wavelength beams absorption, good for atmospheric and vacuum operation, suited for CW (1MW) or short pulses (2MW, 0.ls) precise measurement has been designed to test high power gyrotrons. The common origin for members of this family is a toad developed for the ECRH FTU plant (140 GHz, 0.5 s, 0.5 MW) and successfully exploited. A CW version of the load has been built and used as absorber and bolometer for the high-power test of a remote steering launcher mock-up at 140 GHz. The high-power tests have been performed with powers up to 700 kW and pulse lengths of up to 10 seconds without limitation due to the load. An investigation of the gas emission properties of the load coating material at high temperature and under vacuum has been accomplished by means of high power deposition from an electron gun. Results from these tests are presented.

160. Development of helium electron cyclotron wall conditioning on TCV

Author: Tom Wauters, S. Vartanian, Kevin Verhaegh, A. Moro, P. Blanchard, D. Douai, Lorenzo Figini, Masakatsu Fukumoto, Christian Theiler, Carlo Sozzi, Saul Garavaglia, Y. Miyata, Akihiko Isayama, Timothy Goodman, D. Ricci, M. Silva, and Stefano Coda
Subjects: fusion, ECWC, Nuclear and High Energy Physics, Electron density, Materials science, Cyclotron, Cyclotron resonance, chemistry.chemical_element, 7. Clean energy, 01 natural sciences, Electron cyclotron resonance, 010305 fluids & plasmas, law.invention, symbols.namesake, plasma wall interaction, law, 0103 physical sciences, Langmuir probe, Helium, 010302 applied physics, wall conditioning, Plasma, Condensed Matter Physics, ECRH, Magnetic field, chemistry, symbols, Atomic physics
Abstract: JT-60SA envisions electron cyclotron wall conditioning (ECWC), as wall conditioning method in the presence of the toroidal field to control fuel and impurity recycling and to improve plasma performance and reproducibility. This paper reports on Helium ECWC experiments on TCV in support of JT-60SA operation. Nearly sixty Helium conditioning discharges have been successfully produced in TCV, at a toroidal field B T = 1.3 or 1.54 T, with gyrotrons at 82.7 GHz in X2 mode, mimicking ECWC operation in JT-60SA at the second harmonic of the EC wave. Discharge parameters were tuned in order to (i) minimize the time for the onset of ECWC plasmas, thus minimizing absorption of stray radiation by in-vessel components, (ii) improve discharge homogeneity by extending the discharge vertically and radially, and wall coverage, in particular of inboard surfaces where JT-60SA plasmas will be initiated, (iii) assess the efficiency of He-ECWC to deplete carbon walls from fuel. An optimized combination of vertical and radial magnetic fields, with amplitudes typically 0.1 to 0.6% of that of B T, has been determined, which resulted in lowest breakdown time, improved wall coverage and enhanced fuel removal. A standard ohmic D 2-plasma could be then sustained, whereas it would not have been possible without He-ECWC.
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161. Electromagnetic characterization of the new Martin-Puplett interferometer at JET

Author: S. Garavaglia, Carlo Sozzi, Alessandro Simonetto, and J. Fessey
Subjects: Physics, business.industry, Terahertz radiation, Astrophysics::High Energy Astrophysical Phenomena, Cyclotron, Electron, Radiation, law.invention, Wavelength, Interferometry, Optics, law, Extremely high frequency, business, Coherence (physics)
Abstract: The new multichannel Martin-Puplett interferometer for electron cyclotron emission (ECE) measurements has been working at JET from the 2006 experimental campaign. After the installation, the interferometer has been extensively studied using radiation sources of different wavelengths and coherence. This paper deals with the detailed description of the installation tests performed in the millimeter wave range, and discusses the features and the limits of the different measurements performed.

162. Electron cyclotron stray radiation detection and machine protection system proposal for JT-60SA

Author: Stefano Coda, Paola Platania, D. Ricci, D. Micheletti, Akihiko Isayama, Daniela Farina, Timothy Goodman, Lorenzo Figini, Shinichi Moriyama, Takayuki Kobayashi, D. Douai, Carlo Sozzi, and A. Moro
Subjects: Tokamak, Electron cyclotron, Computer science, Mechanical Engineering, Nuclear engineering, Cyclotron, Electron, Stray radiation, Auxiliary heating, Protection system, 01 natural sciences, 7. Clean energy, 010305 fluids & plasmas, law.invention, Nuclear magnetic resonance, Machine protection, Nuclear Energy and Engineering, law, 0103 physical sciences, General Materials Science, Antenna (radio), 010306 general physics, Beam (structure), Civil and Structural Engineering
Abstract: The JT-60SA tokamak is scheduled to start operations in 2019 to support the ITER experimental programme and to provide key information for the design of DEMO scenarios. The device will count on ECRH and NBI as auxiliary heating. Potentially dangerous situations that could harm the tokamak structures during operations characterized by low EC absorption cannot be a priori excluded. An estimation of the wall load under direct beam exposure and during plasma operations will be given, using the EC antenna main characteristics and launching geometry. A system capable to prevent the risk of damage to machine components for JT-60SA is presented and examples of potential benefits of such a system will be given, based on recent experience gained on the TCV tokamak during EC wall cleaning experiments performed in preparation of JT-60SA operations.
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163. Thermo-mechanical assessment of the JT-60SA fast-ion loss detector

Author: M. Garcia-Munoz, N. Hajnal, Carlo Sozzi, J. Hidalgo-Salaverri, Valerio Tomarchio, M. Wanner, C. Cobacho-Rodriguez, J. Ayllon-Guerola, E. Perelli Cippo, D. García-Vallejo, M. Vallar, M. Verrecchia, Massimo Nocente, S. Davis, Guy Phillips, C. Piccinni, J. Segado-Fernandez, J. Nunez-Portillo, O. Putignano, A. Mancini, Ayllon-Guerola, J, Cobacho-Rodriguez, C, Segado-Fernandez, J, Hidalgo-Salaverri, J, Mancini, A, Nunez-Portillo, J, Garcia-Vallejo, D, Garcia-Munoz, M, Davis, S, Tomarchio, V, Hajnal, N, Piccinni, C, Verrecchia, M, Phillips, G, Vallar, M, Cippo, E, Nocente, M, Putignano, O, Sozzi, C, and Wanner, M
Subjects: Work (thermodynamics), Materials science, Tokamak, Plasma diagnostic, Nuclear engineering, fild, 01 natural sciences, 010305 fluids & plasmas, Ion, law.invention, law, 11. Sustainability, 0103 physical sciences, Thermal, General Materials Science, 010306 general physics, Civil and Structural Engineering, fast ion loss detector, plasma diagnostics, Mechanical Engineering, Detector, Finite element method, jt-60sa, FILDJT-60SA, Nuclear Energy and Engineering, Head (vessel), simulations, mechanical assessment, thermal assessment, Thermo mechanical
Abstract: A fast-ion loss detector (FILD) is being designed for the JT-60SA tokamak. In this work, the preliminary mechanical design of this diagnostic is described. The expected motion needed to move the probe head between the parking and the measuring positions has been estimated by numerical simulations. A finite element thermal assessment of the detector is presented, to characterize its thermal response during the operation of the machine. Finally, the results of a preliminary electromagnetic analysis are reported to evaluate the impact of major disruptions on the structural components the system.
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164. High plasma density lower-hybrid current drive in the FTU Tokamak

Author: L. Gabellieri, C. Gourlan, G. Maddaluno, G. Maffia, E. Barbato, L. Pieroni, Alessandro Simonetto, A. A. Tuccillo, F. Gravanti, F. Santini, R. Cesario, Gustavo Granucci, B. Angelini, E. Giovannozzi, S. Nowak, Gregorio Vlad, Francesco Romanelli, M. Marinucci, G. Buceti, S. E. Segre, L. Lovisetto, A. Bertocchi, M. Sassi, D. Frigione, S. Cirant, A. Imparato, H. Kroegler, E. Sternini, Cristina Centioli, L. Panaccione, Salvatore Podda, D. Pacella, V. Cocilovo, Francesco Mirizzi, S. Ciattaglia, V. Vitale, Alessandro Bruschi, M. Grolli, A. Cardinali, G.B. Righetti, V. Pericoli-Ridolfini, Luciano Bertalot, V. Zanza, B. Tilia, Giovanni Bracco, G. Apruzzese, M. Panella, M. Leigheb, M. Zerbini, N. Tartoni, G. Mazzitelli, Carlo Sozzi, B. Esposito, R. De Angelis, F. De Marco, F. Alladio, P. Buratti, F.P. Orsitto, F. Crisanti, Fulvio Zonca, P. Micozzi, M.L. Apicella, O. Tudisco, M. Borra, and Giancarlo Gatti
Subjects: Nuclear physics, Physics, Part iii, Tokamak, ___, law, High plasma, General Physics and Astronomy, Plasma, Current (fluid), Settore FIS/07 - Fisica Applicata(Beni Culturali, Ambientali, Biol.e Medicin), law.invention
Abstract: s Vol. 19C (European Physical Society, Geneva, 1995), Part III, p. 361. [15] G. Tonon et al., Plasma Phys. Controlled Fusion 35, A105
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165. Real time control developments at JET in preparation for deuterium-tritium operation

Author: Ivo S. Carvalho, R. C. Felton, Daniel F. Valcarcel, M. Lennholm, Carlo Sozzi, C. Guillemaut, L. Garzotti, R. Mooney, Jonathan Graves, K. Cave-Ayland, A. Goodyear, P. J. Lomas, Jesús Vega, E. Lerche, F.G. Rimini, C. D. Challis, D. Frigione, A. C. C. Sips, A. Chagnard, J. R. Harrison, Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear, and Universidad de Sevilla. RNM138: Física Nuclear Aplicada
Subjects: Tritium operation, Computer science, ELMs, Detachment, Nuclear engineering, Automatic frequency control, Context (language use), Sawtooth wave, 7. Clean energy, 01 natural sciences, 010305 fluids & plasmas, Nuclear physics, Fusion, plasma och rymdfysik, Real-time Control System, 0103 physical sciences, General Materials Science, 010306 general physics, Civil and Structural Engineering, Jet (fluid), Mechanical Engineering, Plasma, Real time control, Fusion, Plasma and Space Physics, Power (physics), Isotope control, Plasma termination, Nuclear Energy and Engineering, Cascade, Sawteeth
Abstract: Robust high performance plasma scenarios are being developed to exploit the unique capability of JET to operate with Tritium and Deuterium. In this context, real time control schemes are used to guide the plasma into the desired state and maintain it there. Other real time schemes detect undesirable behaviour and trigger appropriate actions to assure the best experimental results without unnecessary use of the limited neutron and Tritium budget. This paper discusses continuously active controllers and event/threshold detection algorithms triggering a variety of actions. Recent advances include: (i) Control of the degree of plasma detachment via impurity injection; (ii) ELM frequency control via gas/Pellet injection; (iii) Sawtooth pacing using ICRH modulation, (iv) control of the Hydrogen to Deuterium isotope ratio through gas injection and (v) the determination that a discharge is not evolving as desired, triggering a cascade of actions attempting to stop the plasma rapidly and safely, eventually triggering massive gas injection if a disruption is deemed unavoidable. For high power Deuterium-Tritium operation these control schemes need to be integrated into the plasma scenarios ensuring that they are mutually compatible. For complete list of authors see http://dx.doi.org/10.1016/j.fusengdes.2017.05.023

166. Minority and mode conversion heating in (He-3)-H JET plasmas

Author: V. Vdovin, M. Nocente, Yu-Ming Lin, D. Van Eester, E. Lerche, R. C. Felton, T. W. Versloot, Marco Cecconello, T. R. Blackman, M. Maslov, Yevgen O. Kazakov, Carl Hellesen, Vasile Zoita, D. Frigione, M. Lennholm, M. Tardocchi, A. Coyne, I. Coffey, I. Proverbio, Carlo Sozzi, D. Brennan, C. Noble, A. Whitehurst, C. Giroud, P. Beaumont, L. Pangioni, G. Calabrò, A. V. Krasilnikov, A. Czarnecka, A. Brett, E. Wooldridge, Jet-Efda Contributors, M.F. Stamp, W. Studholme, I. Monakhov, S. Knipe, Thomas Johnson, Ph. Jacquet, J. Ongena, M. Gatu Johnson, V. G. Kiptily, Giuseppe Gorini, M.-L. Mayoral, Torbjörn Hellsten, Kristel Crombé, Science and Technology of Nuclear Fusion, Van Eester, D, Lerche, E, Johnson, T, Hellsten, T, Ongena, J, Mayoral, M, Frigione, D, Sozzi, C, Calabro, G, Lennholm, M, Beaumont, P, Blackman, T, Brennan, D, Brett, A, Cecconello, M, Coffey, I, Coyne, A, Crombe, K, Czarnecka, A, Felton, R, Gatu Johnson, M, Giroud, C, Gorini, G, Hellesen, C, Jacquet, P, Kazakov, Y, Kiptily, V, Knipe, S, Krasilnikov, A, Lin, Y, Maslov, M, Monakhov, I, Noble, C, Nocente, M, Pangioni, L, Proverbio, I, Stamp, M, Studholme, W, Tardocchi, M, Versloot, T, Vdovin, V, Whitehurst, A, Wooldridge, E, and Zoita, V
Subjects: plasma-filled waveguide, Tokamak, Materials science, 52.40.Hf Plasma-material interaction, Cyclotron, Resonance, Ion, law.invention, Nuclear magnetic resonance, Ion-Cyclotron, law, ICR, ICP, helicon, Dielectric heating, Wave, 52.50.Qt Plasma heating by radio-frequency field, Plasma, RESONANCE, Condensed Matter Physics, 52.40.Fd Plasma interactions with antenna, FIS/01 - FISICA SPERIMENTALE, Physics and Astronomy, Nuclear Energy and Engineering, TOKAMAK, ION-CYCLOTRON, WAVE, 52.70.Ds Electric and magnetic measurement, Radio frequency, Atomic physics, boundary layer effects, Ion cyclotron resonance
Abstract: Radio frequency (RF) heating experiments have recently been conducted in JET (He-3)-H plasmas. This type of plasmas will be used in ITER's non-activated operation phase. Whereas a companion paper in this same PPCF issue will discuss the RF heating scenario's at half the nominal magnetic field, this paper documents the heating performance in (He-3)-H plasmas at full field, with fundamental cyclotron heating of He-3 as the only possible ion heating scheme in view of the foreseen ITER antenna frequency bandwidth. Dominant electron heating with global heating efficiencies between 30% and 70% depending on the He-3 concentration were observed and mode conversion (MC) heating proved to be as efficient as He-3 minority heating. The unwanted presence of both He-4 and D in the discharges gave rise to 2 MC layers rather than a single one. This together with the fact that the location of the high-field side fast wave (FW) cutoff is a sensitive function of the parallel wave number and that one of the locations of the wave confluences critically depends on the He-3 concentration made the interpretation of the results, although more complex, very interesting: three regimes could be distinguished as a function of X[He-3]: (i) a regime at low concentration (X[He-3] < 1.8%) at which ion cyclotron resonance frequency (ICRF) heating is efficient, (ii) a regime at intermediate concentrations (1.8 < X[He-3] < 5%) in which the RF performance is degrading and ultimately becoming very poor, and finally (iii) a good heating regime at He-3 concentrations beyond 6%. In this latter regime, the heating efficiency did not critically depend on the actual concentration while at lower concentrations (X[He-3] < 4%) a bigger excursion in heating efficiency is observed and the estimates differ somewhat from shot to shot, also depending on whether local or global signals are chosen for the analysis. The different dynamics at the various concentrations can be traced back to the presence of 2 MC layers and their associated FW cutoffs residing inside the plasma at low He-3 concentration. One of these layers is approaching and crossing the low-field side plasma edge when 1.8 < X[He-3] < 5%. Adopting a minimization procedure to correlate the MC positions with the plasma composition reveals that the different behaviors observed are due to contamination of the plasma. Wave modeling not only supports this interpretation but also shows that moderate concentrations of D-like species significantly alter the overall wave behavior in He-3-H plasmas. Whereas numerical modeling yields quantitative information on the heating efficiency, analytical work gives a good description of the dominant underlying wave interaction physics.
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167. Preliminary design of the ITER ECH upper launcher

Author: J.-D. Landis, Gerd Gantenbein, H. Zohm, Timothy Goodman, T.A. Scherer, A. Moro, Daniela Farina, Dirk Strauss, Emanuele Poli, M. deBaar, Burkhard Plaum, W. Kasparek, Gaetano Aiello, Peter Spaeh, K. Kleefeldt, M. A. Henderson, F. Sanchez, Sabine Schreck, René Chavan, G. Saibene, Dennis Ronden, S. Cirant, Alessandro Vaccaro, Carlo Sozzi, O. Sautter, G. Ramponi, Arkady Serikov, and Andreas Meier
Subjects: Physics, Tokamak, Electric power transmission, Plasma heating, law, Nuclear engineering, Sawtooth instability, Cyclotron, Plasma, Electron, Magnetic flux, law.invention
Abstract: The design of the ITER electron cyclotron launchers recently reached the preliminary design level -the last major step before design finalization. The ITER ECH system contains 24 installed gyrotrons providing a maximum ECH injected power of 20 MW through transmission lines towards the tokamak. There are two EC launcher types both using a front steering mirror; one Equatorial Launcher for plasma heating and four Upper Launchers (UL) for plasma mode stabilization (neoclassical tearing modes and the sawtooth instability). A wide steering angle of the ULs allows to focus on magnetic islands which are expected on the rational magnetic flux surfaces q = 1 (sawtooth instability), q = 3/2 and q = 2 (NTMs).

168. Electron cyclotron emission diagnostic of high temperature electron cyclotron resonance heated plasmas on Frascati tokamak upgrade

Author: K. B. Fournier, P. Buratti, Michael Finkenthal, Alessandro Simonetto, D. Pacella, G. Giruzzi, O. Tudisco, M. Zerbini, Gustavo Granucci, Franco Gandini, Carlo Sozzi, Alessandro Bruschi, and S. Cirant
Subjects: Physics, Tokamak, Thomson scattering, Astrophysics::High Energy Astrophysical Phenomena, Frascati Tokamak Upgrade, Cyclotron, Electron, Electron cyclotron resonance, law.invention, Physics::Plasma Physics, law, Electron temperature, Plasma diagnostics, Atomic physics, Instrumentation
Abstract: The electron cyclotron emission (ECE) diagnostic on FTU tokamak is routinely performed with a Michelson interferometer with spectral range extending up to 1300 GHz. The diagnostic allowed accurate electron temperature measurements during the recent 140 GHz electron cyclotron resonance heating (ECRH) experiments on FTU. Very accurate measurements have been performed on a wide range of electron temperatures and profile peaking. The ECE measurements have been compared with Thomson scattering and with observations of x-ray spectra from highly stripped molybdenum ions. The suprathermal emission in these conditions has been studied.

169. Transport and MHD studies at high Te in FTU tokamak

Author: S. Podda, E. Barbato, M.L. Apicella, M. Grolli, Angelo A. Tuccillo, G. Maddaluno, S. E. Segre, M. Marinucci, B Esposito, G. Apruzzese, B. Angelini, V Vitale, C. Centioli, G. Bracco, E. Lazzaro, L Bertalot, G Gatti, Gustavo Granucci, P. Orsitto, P Micozzi, S. Nowak, Giovanna Cenacchi, A. Bertocchi, L Gabellieri, E. Giovannozzi, A. Cardinali, G. Mazzitelli, S Cirant, V. Pericoli, M. Zerbini, V Zanza, D. Pacella, Francesco Romanelli, S. Ciattaglia, S. Sternini, M. Leigheb, D. Frigione, N. Tartoni, R Coelho, L. Pieroni, F. Alladio, G.B. Righetti, Alessandro Simonetto, Carlo Sozzi, F. Iannone, G. Ramponi, R. De Angelis, H. Krögler, M Panella, R. Cesario, F. Gandini, Alessandro Bruschi, V Cocilovo, Gregorio Vlad, G. Buceti, M. Borra, P. Chuilon, O. Tudisco, A Airoldi, F. Crisanti, Fulvio Zonca, P. Buratti, and L. Panaccione
Subjects: Physics, Tokamak, Toroid, Magnetic reconnection, Condensed Matter Physics, Thermal conduction, Settore FIS/07 - Fisica Applicata(Beni Culturali, Ambientali, Biol.e Medicin), Electron cyclotron resonance, Computational physics, law.invention, ___, Nuclear Energy and Engineering, Physics::Plasma Physics, law, Mode coupling, Magnetohydrodynamic drive, Atomic physics, Magnetohydrodynamics
Abstract: Magnetohydrodynamic (MHD) activity and energy transport at rational-q surfaces is analysed on the basis of experimental results on current density profile control obtained with localized electron cyclotron resonance heating (ECRH) on FTU tokamak. The MHD response, in particular 2/1 and 1/1 modes, to ECRH is in agreement with expectations from a theoretical model including resistive wall braking and toroidal mode coupling. It is also shown that the magnetic shear at rq = 1 could control m = 1 mode saturation and magnetic reconnection. Heating results with ECRH at steady state indicate that transport enhancement is the dominant effect on confinement at the q = 2 surface, and suggest that conduction and convection inside the asymmetric m = 1 island should both be taken into account for a proper description of the thermal response to localized ECRH.
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170. An overview of FTU results

Author: William Bin, G. Rocchi, Lorenzo Figini, G. Ramogida, Zwinglio Guimarães-Filho, Daniela Farina, C. Galperti, E. Giovannozzi, S. Nowak, D. Frigione, R. Tulli, H. Kroegler, A. Sibio, M. De Angeli, A. Krivska, S. Garavaglia, L. Di Matteo, M. Vellucci, F. Napoli, P. Petrolini, Sergio Briguglio, B. Angelini, Gregorio Vlad, B. Tilia, F. Gravanti, Giovanni Grossetti, G. Apruzzese, F. Belli, E. Di Ferdinando, Luca Boncagni, A. Cardinali, S. Di Giovenale, V Zanza, L. Gabellieri, G. Maddaluno, C. Di Troia, Gustavo Granucci, Silvio Ceccuzzi, E. Alessi, F. Iannone, G. Mazzitelli, M. Panella, A. Romano, B. Viola, G. Giacomi, Giovanni Grosso, V. Piergotti, G. Calabrò, A. Bertocchi, S. Podda, Gian Luca Ravera, C. Centioli, L. Amicucci, S. Cirant, C. Torelli, B. Raspante, Aldo Pizzuto, A. Grosso, V. Vitale, Angelo A. Tuccillo, O. D'Arcangelo, D. Pacella, V. Pericoli-Ridolfini, Alessandro Bruschi, E. Barbato, M. Zerbini, C. Castaldo, C. Marchetto, M. Marinucci, M. Mezzacappa, G. Pucella, A. Milovanov, M.L. Apicella, P. Cefali, M. Lontano, A. Botrugno, R. Cesario, C. Mazzotta, Carlo Sozzi, M. Aquilini, C. Cianfarani, A. Pensa, R. De Angelis, G.A. Moro, Francesco Mirizzi, E. Lazzaro, Daniele Marocco, D. Zannetti, V. Fusco, D. Minelli, O. Tudisco, G. Fogaccia, G. Artaserse, F. Crisanti, Fulvio Zonca, P. Buratti, Basilio Esposito, F.P. Orsitto, L. Panaccione, V. Mellera, Zannetti, D., Vellucci, M., Tulli, R., Torelli, C., Tilia, B., Sibio, A., Rocchi, G., Raspante, B., Piergotti, V., Petrolini, P., Pensa, A., Mezzacappa, M., Grosso, A., Gravanti, F., Giacomi, G., Di Giovenale, S., Di Ferdinando, E., Cefali, P., Aquilini, M., Zonca, F., Zerbini, M., Zanza, V., Vlad, G., Vitale, V., Viola, B., Tudisco, O., Tuccillo, A. A., Romano, A., Ravera, G., Ramogida, G., Pucella, G., Pizzuto, A., Podda, S., Pericoli-Ridolfini, V., Panella, M., Panaccione, L., Pacella, D., Orsitto, F. P., Mirizzi, F. C., Milovanov, A., Mazzotta, C., Mazzitelli, G., Marocco, D., Marinucci, M., Maddaluno, G., Kroegler, H., Krivska, A., Iannone, F., Giovannozzi, E., Gabellieri, L., Frigione, D., Fogaccia, G., Esposito, B., Di Troia, C., Di Matteo, L., De Angelis, R., Crisanti, F., Cirant, S., Cianfarani, C., Cesario, R., Centioli, C., Castaldo, C., Cardinali, A., Calabrò, G., Bruschi, A., Briguglio, S., Botrugno, A., DE ANGELIS, Riccardo, Calabro, G., Apicella, M. L., and Buratti, P.
Subjects: Physics, Nuclear and High Energy Physics, Safety factor, Cyclotron, Plasma, Sawtooth wave, Condensed Matter Physics, Electron cyclotron resonance, Computational physics, law.invention, Physics::Plasma Physics, Modulation, law, ____, Electric current, Doppler broadening
Abstract: Since the 2010 IAEA-FEC Conference, FTU has exploited improvements in cleaning procedures and in the density control system to complete a systematic exploration of access to high-density conditions in a wide range of plasma currents and magnetic fields. The line-averaged densities at the disruptive limit increased more than linearly with the toroidal field, while no dependence on plasma current was found; in fact, the maximum density of 4.3 × 10 20 m-3 was reached at B = 8 T even at the minimum current of 0.5 MA, corresponding to twice the Greenwald limit. The lack of plasma current dependence was due to the increase in density peaking with the safety factor. Experiments with the 140 GHz electron cyclotron resonance heating (ECRH) system were focused on the sawtooth (ST) period control and on the commissioning of a new launcher with real-time steering capability that will act as the front-end actuator of a real-time system for ST period control and tearing mode stabilization. Various ECRH and electron cyclotron current-drive modulation schemes were used; with the fastest one, the ST period synchronized with an 8 ms modulation period. The observed period variations were simulated using the JETTO code with a critical shear model for the crash trigger. The new launcher was of the plug-in type, allowing quick insertion and connection to the transmission line. Both beam characteristics and steering speed were in line with design expectation. Experimental results on the connection between improved coupling of lower hybrid waves in high-density plasmas and reduced wave spectral broadening were interpreted by fully kinetic, non-linear model calculations. A dual-frequency, time-of-flight diagnostic for the measurement of density profiles was developed and successfully tested. Fishbone-like instabilities driven by energetic electrons were simulated by the hybrid MHD-gyrokinetic XHMGC code. © 2013 IAEA, Vienna.
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171. Progress of the ECRH Upper Launcher design for ITER

Author: Sabine Schreck, Emanuele Poli, C.J.M. Heemskerk, Lorenzo Figini, A. Krause, M. A. Henderson, Timothy Goodman, Gaetano Aiello, Peter Spaeh, Alessandro Bruschi, P. Platania, René Chavan, Olivier Sauter, G. Saibene, Andreas Meier, T.A. Scherer, Daniela Farina, F. Sanchez, W. Kasparek, Dennis Ronden, Burkhard Plaum, J.-D. Landis, Dirk Strauss, B. Weinhorst, V. Garcia, Alessandro Vaccaro, Carlo Sozzi, Arkady Serikov, Mario Gagliardi, Giovanni Grossetti, and A. Moro
Subjects: Physics, Launcher, Mechanical Engineering, Mechanical engineering, Port (circuit theory), Blanket, law.invention, ECRH, Diamond windows, Electric power transmission, Nuclear Energy and Engineering, law, Shield, Shutter, ITER, Extremely high frequency, General Materials Science, Front steering, Spark plug, Beam (structure), Civil and Structural Engineering
Abstract: The design of the ITER ECRH system provides 20 MW millimeter wave power for central plasma heating and MHD stabilization. The system consists of an array of 24 gyrotrons with power supplies coupled to a set of transmission lines guiding the beams to the four upper and the equatorial launcher. The front steering upper launcher design described herein has passed successfully the preliminary design review, and it is presently in the final design stage. The launcher consists of a millimeter wave system and steering mechanism with neutron shielding integrated into an upper port plug with the plasma facing blanket shield module (in-vessel) and a set of ex-vessel waveguides connecting the launcher to the transmission lines. Part of the transmission lines are the ultra-low loss CVD torus diamond windows and a shutter valve, a miter bend section and the feedthroughs integrated in the plug closure plate. These components are connected by corrugated waveguides and form together the first confinement system (FCS). In-vessel, the millimeter-wave system includes a quasi-optical beam propagation system including four mirror sets and a front steering mirror. The millimeter wave system is integrated into a specifically optimized upper port plug providing structural stability to withstand plasma disruption force and the high heat load from the plasma side with a dedicated blanket shield module. A recent update in the ITER interface definition has resulted in the recession of the upper port plug first wall panels, which is now integrated into the design. Apart from the millimeter wave system the upper port plug houses also a set of shield blocks which provide neutron shielding. An overview of the actual ITER ECRH Upper Launcher is given together with some highlights of the design. (C) 2014 Elsevier B.V. All rights reserved.
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172. MHD activity in FTU plasmas with reversed magnetic shear

Author: C. Centioli, V. Pericoli Ridolfini, S. Podda, Marco Ciotti, S. Ciattaglia, A Mancuso, G. Maddaluno, O. Tudisco, M. Grolli, Gregorio Vlad, D. Frigione, G. Buceti, Angelo A. Tuccillo, F. Alladio, G. Maffia, Alessandro Simonetto, Carlo Sozzi, E. Barbato, A. Bertocchi, B. Angelini, D Pacella, P. Buratti, R. De Angelis, G. Apruzzese, M.L. Apicella, G Gatti, H. Kroegler, M Panella, G. Bracco, F. Santini, V Vitale, F. P. Orsitto, L. Panaccione, P Micozzi, S. Sternini, V Zanza, F Valente, B Esposito, L Gabellieri, L. Acitelli, F. Crisanti, L. Pieroni, M. Leigheb, Francesco Mirizzi, R. Cesario, Alessandro Bruschi, A Imparato, V Cocilovo, G. Mazzitelli, C. Gourlan, S Cirant, E. Giovannozzi, F. De Marco, M. Marinucci, Gustavo Granucci, G.B. Righetti, S. E. Segre, L. Lovisetto, M. Zerbini, A. Cardinali, M. Sassi, and Francesco Romanelli
Subjects: Physics, Resistive touchscreen, Safety factor, Tokamak, Plasma, Condensed Matter Physics, law.invention, Shear (sheet metal), ___, Nuclear Energy and Engineering, Physics::Plasma Physics, law, Excited state, Physics::Space Physics, Magnetohydrodynamics, Atomic physics, Excitation
Abstract: The MHD activity of plasma configurations with reversed magnetic shear has been investigated on the FTU tokamak. In the presence of pairs of surfaces with the same rational value q = m/n of the safety factor, double-tearing modes are excited which give rise in most cases to bursts of sawtooth-like profile rearrangements. More stable regimes have also been found, in which the activity is dominated by rotating saturated modes. In a particular case with q(0) approximate to 2.8 and q(min) approximate to 2.5 a discharge without any detectable MHD activity during the current flat-top has been obtained. In high-temperature regimes (T-e x 8 keV at n(e) approximate to 0.8 x 10(20) m(-3)), an irregular activity has been detected near the plasma centre which could be due to the excitation of resistive interchange modes.
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173. Deep neural networks for plasma tomography with applications to JET and COMPASS

Author: J. Denis, M. Tardocchi, Kiptily, M. Koubiti, M. Ghate, R. Michling, G. De Masi, T. Tala, M. Bassan, R. McAdams, S. Dowson, Antoine Merle, Seppo Koivuranta, O. J. Kwon, S. Mahesan, P. Sparapani, A. Malaquias, M. Tsalas, Gennady V. Miloshevsky, M. Vecsei, Michal Stano, E. Lerche, Štefan Matejčík, Piergiorgio Sonato, S. D. Pinches, A. Dal Molin, O. McCormack, B. Colling, F. Mink, Ph. Mertens, P. Drewelow, Nuno Cruz, D. Iglesias, Alessandro Zocco, K. Rathod, S. Collins, F. Koechl, James Buchanan, Andrew West, Francesco Maviglia, E. Stefanikova, David Taylor, B. Graham, T. Lunt, S. Meshchaninov, Arturo Buscarino, G. L. Ravera, Maide Bucolo, J. P. Thomas, S. Foley, B. Wakeling, N. Ashikawa, D. W. Robson, N. J. Conway, V. P. Lo Schiavo, Stefan Buller, Sergey Popovichev, M. Saleem, Jorge Luis Rodriguez, M. Wheatley, Gabriele Croci, Hugo Bufferand, J.F. Artaud, R. C. Felton, O. Kovanda, D. Hepple, K. Dylst, Gabor Szepesi, M. Oberkofler, G.J. van Rooij, N. Teplova, Istvan Cziegler, K. K. Kirov, S. Vartanian, Y. Xue, D. Nina, J. Bernardo, Lorenzo Figini, Guglielmo Rubinacci, Peter Lang, R. Scannell, N. C. Hawkes, P. Denner, Istvan Pusztai, D. D. Carvalho, Salvatore Ventre, A. Lescinskis, Afanasev, C. Hamlyn-Harris, Panagiotis Tolias, R. Vale, T. O'Gorman, S. Lesnoj, I.E. Day, Karol Malinowski, D. Carralero, N. Balshaw, Massimo Angelone, Michaele Freisinger, I. Monakhov, Jesús Vega, Jonathan Citrin, Antti Hakola, H. Patten, P. A. Simmons, Y. Austin, Sehyun Kwak, J. Regana, Rohde, T. Eich, A. Alkseev, R. Lawless, C. G. Elsmore, Fusco, S. Hacquin, S. A. Silburn, A. Fernades, Luigi Fortuna, P. Bunting, R. Sartori, Yuji Hatano, D. Borodin, L. Colas, Daniele Marocco, M. Lennholm, Carlo Sozzi, J. J. Rasmussen, P. McCullen, Tommy Ahlgren, A. Kirschner, Thomas Johnson, M. Rack, Göran Ericsson, Hans Nordman, Jakub Bielecki, P. Merriman, M. Cavedon, G. Hermon, Geert Verdoolaege, K. J. Gibson, Daisuke Nishijima, R. Clarkson, Fuchs, M. Tomes, R. Zagórski, Gerald Pintsuk, W. Higginson, Daniel F. Valcarcel, R. Mooney, K. Dawson, A. Tallargio, T.H. Osborne, P. J. Carvalho, M. Gethins, R. Dux, Pierre Dumortier, G. Urbanczyk, Inessa Bolshakova, R. King, B. Tal, Daniel Tegnered, J. W. Coenen, Leena Aho-Mantila, Eva Belonohy, S. Schmuck, Kai Nordlund, Grégoire Hornung, G. Tvalashvili, M. De Bock, Y. Baranov, G. De Tommasi, A. Urban, L. Forsythe, I. Zychor, J. Dobrashian, E. Clark, Paolo Arena, Alessia Santucci, Ivan Lupelli, S. Nowak, M. Curuia, Jonathan Graves, J. C. Hillesheim, Claudio Verona, Zoita, S. Moon, C. Castaldo, A.V. Stephen, Karl Schmid, A. Sahlberg, C. Di Troia, R. Woodley, L. Garzotti, D. Sandiford, Matthew M. Knight, Juho Leppänen, S. Emery, O. G. Pompilian, M. Goniche, C. Luna, M. Mayer, M. Baruzzo, A. Weckmann, M. Kempenaars, S. Hazel, Fabio Pisano, Claudia Corradino, A. G. Meigs, P. Leichauer, S. Potzel, Stéphane Devaux, C. Piron, G. Saibene, David A Rasmussen, Bruce Lipschultz, A. Di Siena, E. Lazzaro, J. Deane, C. Meadowcroft, C. J. 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Barrera Orte, Tomas Markovic, Yu Gao, A. Lunniss, Z. Vizvary, E. Khilkevich, Th. Puetterich, Dmitry Matveev, E. Perelli Cippo, T. Owen, N. Imazawa, A. Silva, H. P. Summers, Norberto Catarino, Roberto Pasqualotto, P. Muscat, K. Keogh, Ricardo Magnus Osorio Galvao, P. Carman, M. Leyland, E. Veshchev, A. de Castro, M. Gruca, D. C. McDonald, L. Moreira, J. W. Banks, Sanjeev Ranjan, N. Sutton, Iris D. Young, Martin Imrisek, W. Zhang, J. K. Blackburn, Moiseenko, A. Parsloe, T. Loarer, D. N. Borba, S.J. Wukitch, D. P. Coster, J. Penzo, Jose Ramon Martin-Solis, P. Mantica, N. Bekris, M. G. O'Mullane, S. E. Dorling, Yunfeng Liang, S. Gulati, Roberto Ambrosino, J. Schweinzer, Cocilovo, D. Douai, M. A. Henderson, T. Suzuki, Gianluca Rubino, A. Peackoc, Yann Camenen, Y. Miyoshi, Ph. Jacquet, H. T. Lambertz, E. Tholerus, C. Sommariva, Prajapati, Yannick Marandet, F. Hasenbeck, Faa Federico Felici, M. Buckley, Kenneth Hammond, Daniele Milanesio, Cristian Ruset, Katsumichi Hoshino, D. Frigione, D. Chandra, I. Borodkina, P. Dinca, S. Brezinsek, J. Stallard, H. G. Esser, Matthew Sibbald, S. Knipe, Jorge Estrela da Silva, Kensaku Kamiya, P. A. Coates, J. C. Giacalone, Alfredo Pironti, Carvalho, D. D., Ferreira, D. R., Carvalho, P. J., Imrisek, M., Mlynar, J., Fernandes, H., and Formisano, A.
Subjects: Computer science, Feature extraction, Image processing, Computerized Tomography (CT) and Computed Radiography (CR), Plasma diagnostics - interferometry, spectroscopy and imaging, 01 natural sciences, Convolutional neural network, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, 0302 clinical medicine, Compass, Plasma diagnostics-interferometry, spectroscopy and imaging, 0103 physical sciences, Computer vision, Instrumentation, Mathematical Physics, Jet (fluid), Contextual image classification, 010308 nuclear & particles physics, business.industry, Cognitive neuroscience of visual object recognition, Plasma diagnostics - interferometry spectroscopy and imaging, Tomography, Artificial intelligence, business, plasma diagnostics - interferometry, spectroscopy and imaging
Abstract: Convolutional neural networks (CNNs) have found applications in many image processing tasks, such as feature extraction, image classification, and object recognition. It has also been shown that the inverse of CNNs, so- called deconvolutional neural networks, can be used for inverse problems such as plasma tomography. In essence, plasma tomography consists in reconstructing the 2D plasma profile on a poloidal cross-section of a fusion device, based on line-integrated measurements from multiple radiation detectors. Since the reconstruction process is computationally intensive, a deconvolutional neural network trained to produce the same results will yield a significant computational speedup, at the expense of a small error which can be assessed using different metrics. In this work, we discuss the design principles behind such networks, including the use of multiple layers, how they can be stacked, and how their dimensions can be tuned according to the number of detectors and the desired tomographic resolution for a given fusion device. We describe the application of such networks at JET and COMPASS, where at JET we use the bolometer system, and at COMPASS we use the soft X-ray diagnostic based on photodiode arrays.
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174. Runaway electron imaging spectrometry (REIS) system

Author: G. Rocchi, Z. Popovic, A. Grosso, Ftu Team, Jose Ramon Martin-Solis, Carlo Sozzi, R. De Angelis, B. Tilia, A. Sibio, Daniele Carnevale, M. Gospodarczyk, V. Piergotti, P. Buratti, Giorgio Maddaluno, M. Valisa, F. Causa, B. Esposito, Causa, F., Gospodarczyk, M., Buratti, P., Carnevale, D., De Angelis, R., Esposito, B., Grosso, A., Maddaluno, G., Martin-Solis, J. R., Piergotti, V., Popovic, Z., Rocchi, G., Sibio, A., Sozzi, C., Tilia, B., Valisa, M., and European Commission
Subjects: Settore ING-INF/04, Tokamak, Infrared, Synchrotron radiation, Electron, Runaway Electron Imaging and Spectrometry System, Mass spectrometry, 01 natural sciences, Spectral line, 010305 fluids & plasmas, law.invention, Optics, law, Optical systems, 0103 physical sciences, Emission spectrum, Instrumentation, REIS, 010302 applied physics, Physics, LabVIEW program, Spectrometer, business.industry, Física, Emission spectroscopy, FTU, Acquisition systems, business, Tokamaks
Abstract: A portable Runaway Electron Imaging and Spectrometry System (REIS) was developed in ENEA-Frascati to measure synchrotron radiationspectra from in-flight runaway electrons in tokamaks. The REIS is a wide-angle optical system collecting simultaneously visible and infraredemission spectra using an incoherent bundle of fibers, in a spectral range that spans from 500 nm to 2500 nm, and visible images using a CCDcolor microcamera at a rate of 25 frames/s. The REIS system is supervised and managed using a dedicated LabVIEW program to acquire datasimultaneously from three spectrometers every 20 ms (configurable down to 10 ms). An overview of the REIS architecture and acquisitionsystem and resulting experimental data obtained in FTU are presented and discussed in this paper. This work was carried out within the framework of the EUROfusion Consortium (Project No. MST2-15: Runaway Electron Imaging) and received funding from the Euratom research and training programme 2014–2018 under Grant Agreement No. 633053. The views and opinions expressed herein do not necessarily reflect those of the European Commission. The authors would like to thank M. Turnyanskiy, responsible officer for this EUROfusion project, for his continuous support and encouragement throughout this work. Publicado
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175. Wide-angle visible video diagnostics for JT-60SA utilizing EDICAM

Author: G. Kocsis, Tamás Szepesi, S. Davis, N. Hajnal, A. Kovacsik, S. Zoletnik, Carlo Sozzi, Kensaku Kamiya, and Naoyuki Oyama
Subjects: Real-time data processing, JT-60SA, Radiation, 01 natural sciences, 010305 fluids & plasmas, law.invention, Superconducting tokamak, Optics, Video diagnostics, law, 0103 physical sciences, Eddy current, EDICAM, General Materials Science, 010306 general physics, Scientific observation, Spark plug, Civil and Structural Engineering, Physics, business.industry, Mechanical Engineering, Detector, Plasma, Magnetic field, Machine protection, Nuclear Energy and Engineering, business
Abstract: A multi-purpose, wide-angle, visible overview video diagnostic, based on the EDICAM camera, was designed for JT-60SA superconducting tokamak, in order to fulfill both machine protection and scientific observation purposes. The detector is located inside the ‘port plug’ (a ca. 3 m long re-entrant tube), relatively close to the plasma boundary; the EDICAM can tolerate the magnetic field at this location as well as the radiation levels in the early phases of the experiment. A rail-and-carriage system is used to move the detector between the opening of the port plug and the measurement location. A 4-point docking system ensures the precise and robust positioning of the optics, firmly holding the detector also in the event of disruptions or earthquakes. The camera is running under atmospheric condition, separated by a sapphire window from the plasma vacuum. The vacuum window is protected by a water-cooled pin-hole from mechanical impacts and plasma heat; the pin-hole is also the first element of the detector’s optical system. The optics consists of two lens groups and a prism; the housing is made of stainless steel, in order to reduce eddy currents and thus avoid large forces acting on the system in a disruption.
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175 results on '"Carlo Sozzi"'

151. Feedback control of the sawtooth period through real time control of the ion cyclotron resonance frequency

152. Lower hybrid current drive for the steady-state scenario

153. Stationary magnetic entropy tokamak states and experimental observations

154. Analysis of metallic impurity density profiles in low collisionality Joint European Torus H-mode and L-mode plasmas

155. Electric Birefringence of a Dispersion of Electrically Charged Anisotropic Particles

156. Tracking of neoclassical tearing modes in TCV using the electron cyclotron emission diagnostics in quasi-in-line configuration

157. Overview of the TCV tokamak program: scientific progress and facility upgrades

158. Enhanced confinement regimes with strong electron heating in the presence of flat or inverted safety factor profiles

159. Progress of CW and short-pulse calorimetric loads for high power millimeter-wave beams

160. Development of helium electron cyclotron wall conditioning on TCV

161. Electromagnetic characterization of the new Martin-Puplett interferometer at JET

162. Electron cyclotron stray radiation detection and machine protection system proposal for JT-60SA

163. Thermo-mechanical assessment of the JT-60SA fast-ion loss detector

164. High plasma density lower-hybrid current drive in the FTU Tokamak

165. Real time control developments at JET in preparation for deuterium-tritium operation

166. Minority and mode conversion heating in (He-3)-H JET plasmas

167. Preliminary design of the ITER ECH upper launcher

168. Electron cyclotron emission diagnostic of high temperature electron cyclotron resonance heated plasmas on Frascati tokamak upgrade

169. Transport and MHD studies at high Te in FTU tokamak

170. An overview of FTU results

171. Progress of the ECRH Upper Launcher design for ITER

172. MHD activity in FTU plasmas with reversed magnetic shear

173. Deep neural networks for plasma tomography with applications to JET and COMPASS

174. Runaway electron imaging spectrometry (REIS) system

175. Wide-angle visible video diagnostics for JT-60SA utilizing EDICAM

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175 results on '"Carlo Sozzi"'

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