Ion cyclotron resonance frequency (ICRF) heating has been an essential component in the development of high power H-mode scenarios in the Jet European Torus ITER-like wall (JET-ILW). The ICRF performance was improved by enhancing the antenna-plasma coupling with dedicated main chamber gas injection, including the preliminary minimization of RF-induced plasma-wall interactions, while the RF heating scenarios where optimized for core impurity screening in terms of the ion cyclotron resonance position and the minority hydrogen concentration. The impact of ICRF heating on core impurity content in a variety of 2.5 MA JET-ILW H-mode plasmas will be presented, and the steps that were taken for optimizing ICRF heating in these experiments will be reviewed.

VL - 56 UR - http://www.euro-fusionscipub.org/wp-content/uploads/2015/09/WPJET1PR1528.pdf IS - 3 U1 -FP

U2 -TP

U5 - d602ccdf3e42dd82b551d41759691058 ER - TY - JOUR T1 - Real-time control of ELM and sawtooth frequencies: similarities and differences JF - Nuclear Fusion Y1 - 2016 A1 - Lennholm, M. A1 - Frigione, D. A1 - Graves, J. P. A1 - Beaumont, P. S. A1 - Blackman, T. A1 - Carvalho, I. S. A1 - Chapman, I. A1 - Dumont, R. A1 - Felton, R. A1 - Tsalas, M. A1 - Garzotti, L. A1 - Goniche, M. A1 - Goodyear, A. A1 - Grist, D. A1 - Jachmich, S. A1 - Johnson, T. A1 - Lang, P. A1 - Lerche, E. A1 - de la Luna, E. A1 - Monakhov, I. A1 - Mooney, R. A1 - Morris, J. A1 - M F F Nave A1 - Reich, M. A1 - Rimini, F. A1 - Sips, G. A1 - H Sheikh A1 - Sozzi, C. A1 - JET Contributors AB -ELMs and Sawteeth, located in different parts of the plasma, are similar from a control engineering point of view. Both manifest themselves through quiescent periods interrupted by periodic collapses. For both, large collapses, following long quiescent periods, have detrimental effects while short periods are associated with decreased confinement. Following the installation of the all metal ‘ITER like wall’ on JET, sawteeth and ELMs also play an important role by expelling tungsten from the core and edge of the plasma respectively. Control of tungsten has therefore been added to divertor heat load reduction, NTM avoidance and helium ash removal as reasons for requiring ELM and sawtooth control. It is therefore of interest to implement control systems to maintain the sawtooth and ELM frequencies in the desired ranges. On JET, ELM frequency control uses radial field ‘kicks’ and pellet and gas injection as actuators, while sawtooth control uses ion cyclotron resonance heating (ICRH). JET experiments have, for the first time, established feedback control of the ELM frequency, via real time variation of the injected gas flow [1]. Using this controller in conjunction with pellet injection allows the ELM frequency to be kept as required despite variations in pellet ELM triggering efficiency. JET Sawtooth control experiments have, for the first time, demonstrated that low field side ICRH, as foreseen for ITER, can shorten sawteeth lengthened by central fast ions [2]. The development of ELM and sawtooth control could be key to achieve stable high performance JET discharges with minimal tungsten content. Integrating such schemes into an overall control strategy will be required in future tokamaks and gaining experience on current tokamaks is essential.

VL - 56 UR - http://www.euro-fusionscipub.org/wp-content/uploads/2015/05/WPJET1PR1501.pdf IS - 1 U1 -FP

U2 -PDG

U5 - 49c8929abb0e88d6ddf1d8e1ddde5233 ER - TY - JOUR T1 - ELM frequency feedback control on JET JF - Nuclear Fusion Y1 - 2015 A1 - Lennholm, M. A1 - Beaumont, P. S. A1 - Carvalho, I. S. A1 - Chapman, I.T. A1 - Felton, R. A1 - Frigione, D. A1 - Garzotti, L. A1 - Goodyear, A. A1 - Graves, J. A1 - Tsalas, M. A1 - Grist, D. A1 - Jachmich, S. A1 - Lang, P. A1 - Lerche, E. A1 - de la Luna, E. A1 - Mooney, R. A1 - Morris, J. A1 - M F F Nave A1 - Rimini, F. A1 - Sips, G. A1 - Solano, E. A1 - JET-EFDA Contributors AB - This paper describes the first development and implementation of a closed loop edge localized mode (ELM) frequency controller using gas injection as the actuator. The controller has been extensively used in recent experiments on JET and it has proved to work well at ELM frequencies in the 15–40 Hz range. The controller responds effectively to a variety of disturbances, generally recovering the requested ELM frequency within approximately 500 ms. Controlling the ELM frequency has become of prime importance in the new JET configuration with all metal walls, where insufficient ELM frequency is associated with excessive tungsten influx. The controller has allowed successful operation near the minimum acceptable ELM frequency where the best plasma confinement can be achieved. Use of the ELM frequency controller in conjunction with pellet injection has enabled investigations of ELM triggering by pellets while maintaining the desired ELM frequency even when pellets fail to trigger ELMs. VL - 55 U1 - FP U2 - PDG U5 - 3bda42d1e65385a69f8f1e4ab2b8220b ER - TY - JOUR T1 - Sawtooth control in JET with ITER relevant low field side resonance ion cyclotron resonance heating and ITER-like wall JF - Plasma Physics and Controlled Fusion Y1 - 2015 A1 - Graves, J. P. A1 - Lennholm, M. A1 - Chapman, I.T. A1 - Lerche, E. A1 - Reich, M. A1 - Alper, B. A1 - Bobkov, V. A1 - Dumont, R. A1 - Faustin, J. M. A1 - Jacquet, P. A1 - Jaulmes, F. A1 - Johnson, T. A1 - Keeling, D. L. A1 - Liu, Y. Q. A1 - Nicolas, T. A1 - Tholerus, S. A1 - Blackman, T. A1 - Carvalho, I. S. A1 - Coelho, R. A1 - Van Eester, D. A1 - Felton, R. A1 - Goniche, M. A1 - Kiptily, V. A1 - Monakhov, I. A1 - M F F Nave A1 - Perez von Thun, C. A1 - Sabot, R. A1 - Sozzi, C. A1 - Tsalas, M. AB - New experiments at JET with the ITER-like wall show for the first time that ITER-relevant low field side resonance first harmonic ion cyclotron resonance heating (ICRH) can be used to control sawteeth that have been initially lengthened by fast particles. In contrast to previous (Graves et al 2012 Nat. Commun. 3 624) high field side resonance sawtooth control experiments undertaken at JET, it is found that the sawteeth of L-mode plasmas can be controlled with less accurate alignment between the resonance layer and the sawtooth inversion radius. This advantage, as well as the discovery that sawteeth can be shortened with various antenna phasings, including dipole, indicates that ICRH is a particularly effective and versatile tool that can be used in future fusion machines for controlling sawteeth. Without sawtooth control, neoclassical tearing modes (NTMs) and locked modes were triggered at very low normalised beta. High power H-mode experiments show the extent to which ICRH can be tuned to control sawteeth and NTMs while simultaneously providing effective electron heating with improved flushing of high Z core impurities. Dedicated ICRH simulations using SELFO, SCENIC and EVE, including wide drift orbit effects, explain why sawtooth control is effective with various antenna phasings and show that the sawtooth control mechanism cannot be explained by enhancement of the magnetic shear. Hybrid kinetic-magnetohydrodynamic stability calculations using MISHKA and HAGIS unravel the optimal sawtooth control regimes in these ITER relevant plasma conditions. VL - 57 IS - 1 U1 - FP U2 - CPP-HT U5 - 350e787a0d57db2f73d24baa18668ef0 ER - TY - THES T1 - Real time control of the Sawtooth instability in fusions plasmas with large fast ion populations Y1 - 2014 A1 - Lennholm, M. PB - Eindhoven University of Technology CY - Eindhoven, Netherlands VL - PhD SN - 9789462593404 UR - http://repository.tue.nl/783107 U1 - FP U2 - TP U5 - 699526e25e2fd42a5b75cccb429cf981 ER - TY - JOUR T1 - Optimizing ion-cyclotron resonance frequency heating for ITER: dedicated JET experiments (vol 53, 124019, 2011) JF - Plasma Physics and Controlled Fusion Y1 - 2012 A1 - Lerche, E. A1 - Van Eester, D. A1 - Ongena, J. A1 - Mayoral, M. L. A1 - Laxaback, M. A1 - Rimini, F. A1 - Argouarch, A. A1 - Beaumont, P. A1 - Blackman, T. A1 - Bobkov, V. A1 - Brennan, D. A1 - Brett, A. A1 - Calabro, G. A1 - Cecconello, M. A1 - Coffey, I. A1 - Colas, L. A1 - Coyne, A. A1 - Crombe, K. A1 - Czarnecka, A. A1 - Dumont, R. A1 - Durodie, F. A1 - Felton, R. A1 - Frigione, D. A1 - Johnson, M. G. A1 - Giroud, C. A1 - Gorini, G. A1 - Graham, M. A1 - Hellesen, C. A1 - Hellsten, T. A1 - Huygen, S. A1 - Jacquet, P. A1 - Johnson, T. A1 - Kiptily, V. A1 - Knipe, S. A1 - Krasilnikov, A. A1 - Lamalle, P. A1 - Lennholm, M. A1 - Loarte, A. A1 - Maggiora, R. A1 - Maslov, M. A1 - Messiaen, A. A1 - Milanesio, D. A1 - Monakhov, I. A1 - Nightingale, M. A1 - Noble, C. A1 - Nocente, M. A1 - Pangioni, L. A1 - Proverbio, I. A1 - Sozzi, C. A1 - Stamp, M. A1 - Studholme, W. A1 - Tardocchi, M. A1 - Versloot, T. W. A1 - Vdovin, V. A1 - Vrancken, M. A1 - Whitehurst, A. A1 - Wooldridge, E. A1 - Zoita, V. VL - 54 SN - 0741-3335 IS - 6 U1 - FP U2 - PDG U5 - a4876ad5642c6996c71aace8ddbcc77a ER - TY - JOUR T1 - Minority and mode conversion heating in (He-3)-H JET plasmas JF - Plasma Physics and Controlled Fusion Y1 - 2012 A1 - Van Eester, D. A1 - Lerche, E. A1 - Johnson, T. J. A1 - Hellsten, T. A1 - Ongena, J. A1 - Mayoral, M. L. A1 - Frigione, D. A1 - Sozzi, C. A1 - Calabro, G. A1 - Lennholm, M. A1 - Beaumont, P. A1 - Blackman, T. A1 - Brennan, D. A1 - Brett, A. A1 - Cecconello, M. A1 - Coffey, I. A1 - Coyne, A. A1 - Crombe, K. A1 - Czarnecka, A. A1 - Felton, R. A1 - Johnson, M. G. A1 - Giroud, C. A1 - Gorini, G. A1 - Hellesen, C. A1 - Jacquet, P. A1 - Kazakov, Y. A1 - Kiptily, V. A1 - Knipe, S. A1 - Krasilnikov, A. A1 - Lin, Y. A1 - Maslov, M. A1 - Monakhov, I. A1 - Noble, C. A1 - Nocente, M. A1 - Pangioni, L. A1 - Proverbio, I. A1 - Stamp, M. A1 - Studholme, W. A1 - Tardocchi, M. A1 - Versloot, T. W. A1 - Vdovin, V. A1 - Whitehurst, A. A1 - Wooldridge, E. A1 - Zoita, V. KW - ION-CYCLOTRON KW - RESONANCE KW - TOKAMAK KW - WAVE AB - 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. VL - 54 SN - 0741-3335 IS - 7 U1 - FP U2 - PDG U5 - 5afe644491b42921b17bd4827511caac ER - TY - JOUR T1 - Observations of rotation in JET plasmas with electron heating by ion cyclotron resonance heating JF - Plasma Physics and Controlled Fusion Y1 - 2012 A1 - Hellsten, T. A1 - Johnson, T. J. A1 - Van Eester, D. A1 - Lerche, E. A1 - Lin, Y. A1 - Mayoral, M. L. A1 - Ongena, J. A1 - Calabro, G. A1 - Crombe, K. A1 - Frigione, D. A1 - Giroud, C. A1 - Lennholm, M. A1 - Mantica, P. A1 - M F F Nave A1 - Naulin, V. A1 - Sozzi, C. A1 - Studholme, W. A1 - Tala, T. A1 - Versloot, T. KW - ALCATOR C-MOD KW - CONVERSION KW - ICRF KW - IMPURITY TOROIDAL ROTATION KW - MOMENTUM INPUT KW - OHMIC H-MODE KW - TCV TOKAMAK KW - TRANSPORT KW - UPGRADE AB - The rotation of L-mode plasmas in the JET tokamak heated by waves in the ion cyclotron range of frequencies (ICRF) damped on electrons, is reported. The plasma in the core is found to rotate in the counter-current direction with a high shear and in the outer part of the plasma with an almost constant angular rotation. The core rotation is stronger in magnitude than observed for scenarios with dominating ion cyclotron absorption. Two scenarios are considered: the inverted mode conversion scenarios and heating at the second harmonic He-3 cyclotron resonance in H plasmas. In the latter case, electron absorption of the fast magnetosonic wave by transit time magnetic pumping and electron Landau damping (TTMP/ELD) is the dominating absorption mechanism. Inverted mode conversion is done in (He-3)-H plasmas where the mode converted waves are essentially absorbed by electron Landau damping. Similar rotation profiles are seen when heating at the second harmonic cyclotron frequency of He-3 and with mode conversion at high concentrations of He-3. The magnitude of the counter-rotation is found to decrease with an increasing plasma current. The correlation of the rotation with the electron temperature is better than with coupled power, indicating that for these types of discharges the dominating mechanism for the rotation is related to indirect effects of electron heat transport, rather than to direct effects of ICRF heating. There is no conclusive evidence that mode conversion in itself affects rotation for these discharges. VL - 54 SN - 0741-3335 UR - http://iopscience.iop.org/0741-3335/54/7/074007/ U1 - FP U2 - PDG U5 - 93740712309ac4cdd84e5f589db2cc2f ER - TY - JOUR T1 - Experimental investigation of ion cyclotron range of frequencies heating scenarios for ITER's half-field hydrogen phase performed in JET JF - Plasma Physics and Controlled Fusion Y1 - 2012 A1 - Lerche, E. A1 - Van Eester, D. A1 - Johnson, T. J. A1 - Hellsten, T. A1 - Ongena, J. A1 - Mayoral, M. L. A1 - Frigione, D. A1 - Sozzi, C. A1 - Calabro, G. A1 - Lennholm, M. A1 - Beaumont, P. A1 - Blackman, T. A1 - Brennan, D. A1 - Brett, A. A1 - Cecconello, M. A1 - Coffey, I. A1 - Coyne, A. A1 - Crombe, K. A1 - Czarnecka, A. A1 - Felton, R. A1 - Giroud, C. A1 - Gorini, G. A1 - Hellesen, C. A1 - Jacquet, P. A1 - Kiptily, V. A1 - Knipe, S. A1 - Krasilnikov, A. A1 - Maslov, M. A1 - Monakhov, I. A1 - Noble, C. A1 - Nocente, M. A1 - Pangioni, L. A1 - Proverbio, I. A1 - Sergienko, G. A1 - Stamp, M. A1 - Studholme, W. A1 - Tardocchi, M. A1 - Vdovin, V. A1 - Versloot, T. A1 - Voitsekhovitch, I. A1 - Whitehurst, A. A1 - Wooldridge, E. A1 - Zoita, V. A1 - JET-EFDA Contributors AB - Two ion cyclotron range of frequencies (ICRF) heating schemes proposed for the half-field operation phase of ITER in hydrogen plasmas—fundamental H majority and second harmonic 3 He ICRF heating—were recently investigated in JET. Although the same magnetic field and RF frequencies ( f ≈ 42 MHz and f ≈ 52 MHz, respectively) were used, the density and particularly the plasma temperature were lower than those expected in the initial phase of ITER. Unlike for the well-performing H minority heating scheme to be used in 4 He plasmas, modest heating efficiencies ( η = P absorbed / P launched < 40%) with dominant electron heating were found in both H plasma scenarios studied, and enhanced plasma–wall interaction manifested by high radiation losses and relatively large impurity content in the plasma was observed. This effect was stronger in the 3 He ICRF heating case than in the H majority heating experiments and it was verified that concentrations as high as ∼20% are necessary to observe significant ion heating in this case. The RF acceleration of the heated ions was modest in both cases, although a small fraction of the 3 He ions reached about 260 keV in the second harmonic 3 He heating experiments when 5 MW of ICRF power was applied. Considerable RF acceleration of deuterium beam ions was also observed in some discharges of the 3 He heating experiments (where both the second and third harmonic ion cyclotron resonance layers of the D ions are inside the plasma) whilst it was practically absent in the majority hydrogen heating scenario. While hints of improved RF heating efficiency as a function of the plasma temperature and plasma dilution (with 4 He) were confirmed in the H majority case, the 3 He concentration was the main handle on the heating efficiency in the second harmonic 3 He heating scenario. VL - 54 UR - http://stacks.iop.org/0741-3335/54/i=7/a=074008 U1 - FP U2 - PDG U5 - c7586e86396bb14ec0592fd5272dde01 ER - TY - JOUR T1 - ECRH for JET: A feasibility study JF - Fusion Engineering and Design Y1 - 2011 A1 - Lennholm, M. A1 - Giruzzi, G. A1 - Parkin, A. A1 - Bouquey, F. A1 - Braune, H. A1 - Bruschi, A. A1 - de la Luna, E. A1 - Denisov, G. A1 - Edlington, T. A1 - Farina, D. A1 - Farthing, J. A1 - Figini, L. A1 - Garavaglia, S. A1 - J. Garcia A1 - Gerbaud, T. A1 - Granucci, G. A1 - Henderson, M. A1 - Horton, L. A1 - Kasparek, W. A1 - Khilar, P. A1 - Jennison, M. A1 - Kirneva, N. A1 - Kislov, D. A1 - Kuyanov, A. A1 - X. Litaudon A1 - Litvak, A. G. A1 - Moro, A. A1 - Nowak, S. A1 - Parail, V. A1 - Plaum, B. A1 - Rimini, F. A1 - Saibene, G. A1 - Sips, A. A1 - Sozzi, C. A1 - Späh, P. A1 - Trukhina, E. A1 - Vaccaro, A. A1 - Vdovin, V. KW - CURRENT DRIVE KW - electron cyclotron resonance heating KW - gyrotron KW - launcher KW - transmission line AB -For JET to fulfil its mission in preparing ITER operation, the installation of an electron cyclotron resonance heating system on JET would be desirable. The study described in this paper has investigated the feasibility of installing such a system on JET. The principal goals of such a system are: current drive over a range of radii for NTM stabilization, sawtooth control and current profile tailoring and central electron heating to equilibrate electron and ion temperatures in high performance discharges. The study concluded that a 12 gyrotron, 10 MW, system at the ITER frequency (170 GHz) adapted for fields of 2.7-3.3 T would be appropriate for the operation planned in JET. An antenna allowing toroidal and poloidal steering over a wide range is being designed, using the ITER upper launcher steering mechanism. The use of ITER diamond windows and transmission line technology is suggested while power supply solutions partially reusing existing JET power supplies are proposed. Detailed planning shows that such a system can be operational in about 5 years from the time that the decision to proceed is taken. The cost and required manpower associated with implementing such a system on JET has also been estimated. (C) 2011 EURATOM. Published by Elsevier B.V. All rights reserved.

VL - 86 SN - 0920-3796 IS - 6-8 N1 - ISI Document Delivery No.: 853KZTimes Cited: 0Cited Reference Count: 2126th Symposium on Fusion Technology (SOFT)SEP 27-OCT 01, 2010Porto, PORTUGALInst Plasmas Fusao Nucl (IPFN), Commiss European Union, Inst Soldadura Qualidade (ISQ), Fundacao Ciencia Tecnologia (FCT), Univ Tecnica Lisboa (UTL), TAP, Andante U1 -FP

U2 -TP

U5 - 5591da4092462cfd1e886148d5d553ed ER - TY - JOUR T1 - Objectives, physics requirements and conceptual design of an ECRH system for JET JF - Nuclear Fusion Y1 - 2011 A1 - Giruzzi, G. A1 - Lennholm, M. A1 - Parkin, A. A1 - Aiello, G. A1 - Bellinger, M. A1 - Bird, J. A1 - Bouquey, F. A1 - Braune, H. A1 - Bruschi, A. A1 - Butcher, P. A1 - Clay, R. A1 - de la Luna, E. A1 - Denisov, G. A1 - Edlington, T. A1 - Fanthome, J. A1 - Farina, D. A1 - Farthing, J. A1 - Figini, L. A1 - Garavaglia, S. A1 - J. Garcia A1 - Gardener, M. A1 - Gerbaud, T. A1 - Granucci, G. A1 - Hay, J. A1 - Henderson, M. A1 - Hotchin, S. A1 - Ilyin, V. N. A1 - Jennison, M. A1 - Kasparek, W. A1 - Khilar, P. A1 - Kirneva, N. A1 - Kislov, D. A1 - Knipe, S. A1 - Kuyanov, A. A1 - X. Litaudon A1 - Litvak, A. G. A1 - Moro, A. A1 - Nowak, S. A1 - Parail, V. A1 - Plaum, B. A1 - Saibene, G. A1 - Sozzi, C. A1 - Späh, P. A1 - Strauss, D. A1 - Trukhina, E. A1 - Vaccaro, A. A1 - Vagdama, A. A1 - Vdovin, V. KW - CURRENT DRIVE KW - ITER KW - MODEL KW - PROGRESS KW - SAWTOOTH PERIOD AB -A study has been conducted to evaluate the feasibility of installing an electron cyclotron resonance heating (ECRH) and current drive system on the JET tokamak. The main functions of this system would be electron heating, sawtooth control, neoclassical tearing mode control to access high beta regimes and current profile control to access and maintain advanced plasma scenarios. This paper presents an overview of the studies performed in this framework by an EU-Russia project team. The motivations for this major upgrade of the JET heating systems and the required functions are discussed. The main results of the study are summarized. The usefulness of a 10 MW level EC system for JET is definitely confirmed by the physics studies. Neither feasibility issues nor strong limitations for any of the functions envisaged have been found. This has led to a preliminary conceptual design of the system.

VL - 51 SN - 0029-5515 IS - 6 N1 - ISI Document Delivery No.: 766MWTimes Cited: 2Cited Reference Count: 37 U1 -FP

U2 -TP

U5 - e451b1911c468bfd0a4f2e7f751d6c9f ER - TY - JOUR T1 - Feedback control of the sawtooth period through real time control of the ion cyclotron resonance frequency JF - Nuclear Fusion Y1 - 2011 A1 - Lennholm, M. A1 - Blackman, T. A1 - Chapman, I.T. A1 - Eriksson, L. G. A1 - Graves, J. P. A1 - Howell, D. F. A1 - de M. Baar A1 - Calabro, G. A1 - Dumont, R. A1 - Graham, M. A1 - Jachmich, S. A1 - Mayoral, M. L. A1 - Sozzi, C. A1 - Stamp, M. A1 - Tsalas, M. A1 - P. de Vries KW - CURRENT DRIVE KW - JET TOKAMAK KW - JOINT EUROPEAN TORUS KW - LIMITS KW - PHYSICS KW - RANGE KW - SAWTEETH KW - STABILIZATION AB -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.

VL - 51 SN - 0029-5515 IS - 7 N1 - ISI Document Delivery No.: 781LITimes Cited: 0Cited Reference Count: 33 U1 -FP

U2 -TP

U5 - 3a300f8d24d4120bf95271a0e659cadb ER - TY - JOUR T1 - Optimizing ion-cyclotron resonance frequency heating for ITER: dedicated JET experiments JF - Plasma Physics and Controlled Fusion Y1 - 2011 A1 - Lerche, E. A1 - Van Eester, D. A1 - Ongena, J. A1 - Mayoral, M. L. A1 - Laxaback, M. A1 - Rimini, F. A1 - Argouarch, A. A1 - Beaumont, P. A1 - Blackman, T. A1 - Bobkov, V. A1 - Brennan, D. A1 - Brett, A. A1 - Calabro, G. A1 - Cecconello, M. A1 - Coffey, I. A1 - Colas, L. A1 - Coyne, A. A1 - Crombe, K. A1 - Czarnecka, A. A1 - Dumont, R. A1 - Durodie, F. A1 - Felton, R. A1 - Frigione, D. A1 - Johnson, M. G. A1 - Giroud, C. A1 - Gorini, G. A1 - Graham, M. A1 - Hellesen, C. A1 - Hellsten, T. A1 - Huygen, S. A1 - Jacquet, P. A1 - Johnson, T. A1 - Kiptily, V. A1 - Knipe, S. A1 - Krasilnikov, A. A1 - Lamalle, P. A1 - Lennholm, M. A1 - Loarte, A. A1 - Maggiora, R. A1 - Maslov, M. A1 - Messiaen, A. A1 - Milanesio, D. A1 - Monakhov, I. A1 - Nightingale, M. A1 - Noble, C. A1 - Nocente, M. A1 - Pangioni, L. A1 - Proverbio, I. A1 - Sozzi, C. A1 - Stamp, M. A1 - Studholme, W. A1 - Tardocchi, M. A1 - Versloot, T. W. A1 - Vdovin, V. A1 - Vrancken, M. A1 - Whitehurst, A. A1 - Wooldridge, E. A1 - Zoita, V. KW - DESIGN KW - ICRF ANTENNAS KW - MODE CONVERSION KW - PLASMAS KW - Sawtooth KW - SCENARIOS KW - SYSTEM KW - TOKAMAK AB -In the past years, one of the focal points of the JET experimental programme was on ion-cyclotron resonance heating (ICRH) studies in view of the design and exploitation of the ICRH system being developed for ITER. In this brief review, some of the main achievements obtained in JET in this field during the last 5 years will be summarized. The results reported here include important aspects of a more engineering nature, such as (i) the appropriate design of the RF feeding circuits for optimal load resilient operation and (ii) the test of a compact high-power density antenna array, as well as RF physics oriented studies aiming at refining the numerical models used for predicting the performance of the ICRH system in ITER. The latter include (i) experiments designed for improving the modelling of the antenna coupling resistance under various plasma conditions and (ii) the assessment of the heating performance of ICRH scenarios to be used in the non-active operation phase of ITER.

VL - 53 SN - 0741-3335 IS - 12 N1 - ISI Document Delivery No.: 870BLTimes Cited: 0Cited Reference Count: 43Part 1-2 U1 -FP

U2 -PDG

U5 - 5271f643f9b6df31138d568a0bcdbc8b ER - TY - JOUR T1 - TORE SUPRA Team Mmembers 1988-2008 JF - Fusion Science and Technology Y1 - 2009 A1 - Abgrall, R. A1 - Achard, M. H. A1 - Adam, J. A1 - Agarici, G. A1 - Agostini, E. A1 - Airaj, M. A1 - Albajar-Vinas, F. A1 - Allegretti, L. A1 - Allibert, J. P. A1 - Alliez, J. C. A1 - Allouche, A. A1 - Andreoletti, J. A1 - Ane, J. M. A1 - Angelino, P. A1 - Aniel, T. A1 - Antar, G. A1 - Arcis, N. A1 - Argouarch, A. A1 - Arnas, C. A1 - Arnoux, G. A1 - Arslanbekov, R. A1 - Artaud, J. F. A1 - Asp, E. A1 - Assas, S. A1 - Atttuel, G. A1 - Aymar, R. A1 - Azeroual, A. A1 - Balme, S. A1 - Barana, O. A1 - Bareyt, B. A1 - Basiuk, V. A1 - Basko, M. A1 - Bayetti, P. A1 - Baylor, L. A1 - Beaumont, B. A1 - Becherer, R. A1 - Becoulet, A. A1 - Becoulet, M. A1 - Begrambekov, L. A1 - Benkadda, S. A1 - Benoit, F. A1 - Bergeaud, V. A1 - Berger-By, G. A1 - Berio, S. A1 - Bernascolle, P. A1 - Bernier, N. A1 - Berroukeche, M. A1 - Bertrand, B. A1 - Bessette, D. A1 - Beyer, P. A1 - Bibet, P. A1 - Bizzaro, J. A1 - Blanchard, P. A1 - Blum, J. A1 - Boddeker, S. A1 - Boilson, D. A1 - Mardion, G. B. A1 - Bonnel, P. A1 - Bonnin, X. A1 - Boscary, J. A1 - Bosia, G. A1 - Bottereau, J. M. A1 - Bottiglioni, F. A1 - Bottollier-Curtet, H. A1 - Bouchand, C. A1 - Bouligand, G. A1 - Bouquey, F. A1 - Bourdelle, C. A1 - Bregeon, R. A1 - Bremond, F. A1 - Bremond, S. A1 - Breton, C. A1 - Breton, M. A1 - Brosset, C. A1 - Brugnetti, R. A1 - Bruneau, J. L. A1 - Bucalossi, J. A1 - Budny, R. V. A1 - Buravand, Y. A1 - Bush, C. A1 - Bussac, M. N. A1 - Cambe, A. A1 - Capes, H. A1 - Capitain, J. J. A1 - Cara, P. A1 - Carbonnier, J. L. A1 - Carpentier, S. A1 - Carrasco, J. A1 - Casati, A. A1 - Chaibi, O. A1 - Chamouard, C. A1 - Chantant, M. A1 - Chappuis, P. A1 - Chatain, D. A1 - Chatelier, E. A1 - Chatelier, M. A1 - Chatenet, J. H. A1 - Chen, X. P. A1 - Cherigier, L. A1 - Chevet, G. A1 - Chiarazzo, L. A1 - Ciazynski, D. A1 - Ciraolo, G. A1 - Cismondi, F. A1 - Clairet, F. A1 - Clary, J. A1 - Clement, C. A1 - Colas, L. A1 - Commaux, N. A1 - Corbel, E. A1 - Cordier, J. J. A1 - Corre, Y. A1 - Costanzo, L. A1 - Cote, A. A1 - Coulon, J. P. A1 - Courtois, L. A1 - Courtois, X. A1 - Couturier, B. A1 - Crenn, J. P. A1 - Cristofani, P. A1 - Crouseilles, N. A1 - Czarny, O. A1 - Rosa, P. D. A1 - Darbos, C. A1 - Darmet, G. A1 - Davi, M. A1 - Daviot, R. A1 - De Esch, H. A1 - De Gentile, B. A1 - De Haas, J. C. A1 - De La Cal, E. A1 - De Michelis, C. A1 - Deck, C. A1 - Decker, J. A1 - Decool, P. A1 - Degond, P. A1 - Dejarnac, R. A1 - Delchambre, E. A1 - Delmas, E. A1 - Delpech, L. A1 - Demarthe, H. A1 - Dentan, M. A1 - Depret, G. A1 - Deschamps, P. A1 - Desgranges, C. A1 - Devynck, P. A1 - Doceul, L. A1 - Dolgetta, N. A1 - Doloc, C. A1 - Dong, Y. A1 - Dore, P. A1 - Douai, D. A1 - Dougnac, H. A1 - Drawin, H. W. A1 - Druaux, J. A1 - Druetta, M. A1 - Dubois, F. A1 - Dubois, M. A1 - Dubuit, N. A1 - Duchateau, J. L. A1 - de Wit, T. D. A1 - Dufour, E. A1 - Dumont, R. A1 - Dunand, G. A1 - Dupas, L. A1 - Duran, Y. A1 - Durocher, A. A1 - Edery, D. A1 - Ekedahl, A. A1 - Elbeze, D. A1 - Eriksson, L. G. A1 - Escande, D. A1 - Escarguel, A. A1 - Escourbiac, F. A1 - Evans, T. A1 - Faisse, F. A1 - Falchetto, G. A1 - Fall, T. A1 - Farge, M. A1 - Farjon, J. L. A1 - Faudot, E. A1 - Fazilleau, P. A1 - Fedorczak, N. A1 - Fenzi-Bonizec, C. A1 - Ferron, J. R. A1 - Fidone, I. A1 - Figarella, C. A1 - Fleurence, E. A1 - Fleury, I. A1 - Fois, M. A1 - Forrest, C. A1 - Foster, C. A. A1 - Fouquet, S. A1 - Fourment, C. A1 - Fraboulet, D. A1 - Francois, P. A1 - Franel, B. A1 - Frigione, D. A1 - Froissard, P. A1 - Fubiani, G. A1 - Fuchs, V. A1 - Fumelli, M. A1 - Gagey, B. A1 - Galindo, V. A1 - Gambier, D. A1 - Garampon, L. A1 - Garbet, X. A1 - Garbil, R. A1 - J. Garcia A1 - Gardarein, J. L. A1 - Gargiulo, L. A1 - Garibaldi, P. A1 - Garin, P. A1 - Gauthier, E. A1 - Geraud, A. A1 - Gerbaud, T. A1 - Gervais, F. A1 - Geynet, M. A1 - Ghendrih, P. A1 - Gianakon, T. A1 - Giannella, R. A1 - Gil, C. A1 - Girard, J. P. A1 - Giruzzi, G. A1 - Godbert-Mouret, L. A1 - Gomez, P. A1 - Goniche, M. A1 - Gordeev, A. A1 - Granata, G. A1 - Grandgirard, V. A1 - Gravier, R. A1 - Gravil, B. A1 - Gregoire, M. A1 - Gregoire, S. A1 - Grelot, P. A1 - Gresillon, D. A1 - Grisolia, C. A1 - Gros, G. A1 - Grosman, A. A1 - Grua, P. A1 - Guerin, O. A1 - Guigon, R. A1 - Guilhem, D. A1 - Guillerminet, B. A1 - Guirlet, R. A1 - Guiziou, L. A1 - Gunn, J. A1 - Hacquin, S. A1 - Harris, J. A1 - Haste, G. A1 - Hatchressian, J. C. A1 - Hemsworth, R. A1 - Hennequin, P. A1 - Hennion, F. A1 - Hennion, V. A1 - Henry, D. A1 - Hernandez, C. A1 - Hertout, P. A1 - Hess, W. A1 - Hesse, M. A1 - Heuraux, S. A1 - Hillairet, J. A1 - Hoang, G. T. A1 - Hogan, J. A1 - Hong, S. H. A1 - Honore, C. A1 - Horton, L. A1 - Horton, W. W. A1 - Houlberg, W. A. A1 - Hourtoule, J. A1 - Houry, M. A1 - Houy, P. A1 - How, J. A1 - Hron, M. A1 - Hutter, T. A1 - Huynh, P. A1 - Huysmans, G. A1 - Idmtal, J. A1 - Imbeaux, F. A1 - Isler, R. A1 - Jaben, C. A1 - Jacquinot, J. A1 - Jacquot, C. A1 - Jager, B. A1 - Jaunet, M. A1 - Javon, C. A1 - Jelea, A. A1 - Jequier, F. A1 - Jie, Y. X. A1 - Jimenez, R. A1 - Joffrin, E. A1 - Johner, J. A1 - Jourd'heuil, L. A1 - Journeaux, J. Y. A1 - Joyer, P. A1 - Ju, M. A1 - Jullien, F. A1 - Junique, F. A1 - Kaye, S. M. A1 - Kazarian, F. A1 - Khodja, H. A1 - Klepper, C. A1 - Kocan, M. A1 - Koski, J. A1 - Krivenski, V. A1 - Krylov, A. A1 - Kupfer, K. A1 - Kuus, H. A1 - Labit, B. A1 - Laborde, L. A1 - Lacroix, B. A1 - Ladurelle, L. A1 - Lafon, D. A1 - Lamaison, V. A1 - Laporte, P. A1 - Lasalle, J. A1 - Latu, G. A1 - Laugier, F. A1 - Laurent, L. A1 - Lausenaz, Y. A1 - Laviron, C. A1 - Layet, J. M. A1 - Le Bris, A. A1 - Le Coz, F. A1 - Le Niliot, C. A1 - Le Bris, A. A1 - Leclert, G. A1 - Lecoustey, P. A1 - Ledyankinc, A. A1 - Leloup, C. A1 - Lennholm, M. A1 - Leroux, F. A1 - Li, Y. Y. A1 - Libeyre, P. A1 - Linez, F. A1 - Lipa, M. A1 - Lippmann, S. A1 - X. Litaudon A1 - Liu, W. D. A1 - Loarer, T. A1 - Lott, F. A1 - Lotte, P. A1 - Lowry, C. A1 - Luciani, J. F. A1 - Lutjens, H. A1 - Luty, J. A1 - Lutz, T. A1 - Lyraud, C. A1 - Maas, A. A1 - Macor, A. A1 - Madeleine, S. A1 - Magaud, P. A1 - Maget, P. A1 - Magne, R. A1 - Mahdavi, A. A1 - Mahe, F. A1 - J. Mailloux A1 - Mandl, W. A1 - Manenc, L. A1 - Marandet, Y. A1 - Marbach, G. A1 - Marechal, J. L. A1 - Martin, C. A1 - Martin, G. A1 - Martin, V. A1 - Martinez, A. A1 - Martins, J. P. A1 - Maschke, E. A1 - Masse, L. A1 - Masset, R. A1 - Massmann, P. A1 - Mattioli, M. A1 - Mayaux, G. A1 - Mayoral, M. L. A1 - Mazon, D. A1 - McGrath, R. A1 - Mercier, C. A1 - Meslin, B. A1 - Meunier, L. A1 - Meyer, O. A1 - Michelot, Y. A1 - Million, L. A1 - Millot, P. A1 - Minguella, G. A1 - Minot, F. A1 - Mioduszewski, P. A1 - Misguich, J. H. A1 - Miskane, F. A1 - Missirlian, M. A1 - Mitteau, R. A1 - Moerel, F. A1 - Mollard, P. A1 - Monakhov, I. A1 - Moncada, V. A1 - Moncel, L. A1 - Monier-Garbet, P. A1 - Moreau, D. A1 - Moreau, F. A1 - Moreau, P. A1 - Morera, J. P. A1 - Moret, J. M. A1 - Moulin, B. A1 - Moulin, D. A1 - Mourgues, F. A1 - Moustier, M. A1 - Nakach, R. A1 - Nannini, M. A1 - Nanobashvili, I. A1 - Nardon, E. A1 - Navarra, P. A1 - Nehme, H. A1 - Nguyen, C. A1 - Nguyen, F. A1 - Nicollet, S. A1 - Nygren, R. A1 - Ogorodnikova, O. A1 - Olivain, J. A1 - Orlandelli, P. A1 - Ottaviani, M. A1 - Ouvrier-Buffet, P. A1 - Ouyang, Z. A1 - Owen, L. A1 - Pacella, D. A1 - Pain, M. A1 - Pamela, J. A1 - Pamela, S. A1 - Panek, R. A1 - Panzarella, A. A1 - Paris, R. A1 - Parisot, T. A1 - Park, S. H. A1 - Parlange, F. A1 - Parrat, H. A1 - Pastor, G. A1 - Pastor, P. A1 - Pastor, T. A1 - Patris, R. A1 - Paume, M. A1 - Payan, J. A1 - Pecquet, A. L. A1 - Pegourie, B. A1 - Petrov, Y. A1 - Petrzilka, V. A1 - Peysson, Y. A1 - Piat, D. A1 - Picchiottino, J. M. A1 - Pierre, J. A1 - Platz, P. A1 - Portafaix, C. A1 - Prou, M. A1 - Pugno, R. A1 - Putchy, L. A1 - Qin, C. M. A1 - Quallis, L. A1 - Quemeneur, A. A1 - Quet, P. A1 - Rabaglino, E. A1 - Raharijaona, J. J. A1 - Ramette, J. A1 - Ravenel, N. A1 - Rax, J. M. A1 - Reichle, R. A1 - Renard, B. A1 - Renner, H. A1 - Reuss, J. D. A1 - Reux, C. A1 - Reverdin, C. A1 - Rey, G. A1 - Reynaud, P. A1 - Riband, P. H. A1 - Richou, M. A1 - Rigollet, F. A1 - Rimini, F. A1 - Riquet, D. A1 - Rochard, F. A1 - Rodriguez, L. A1 - Romanelli, M. A1 - Romannikov, A. A1 - Rosanvallon, S. A1 - Roth, J. A1 - Rothan, B. A1 - Roubin, J. P. A1 - Roubin, P. A1 - Roupillard, G. A1 - Roussel, P. A1 - Ruggieri, R. A1 - Sabathier, F. A1 - Sabbagh, S. A. A1 - Sabot, R. A1 - Saha, S. K. A1 - Saint-Laurent, F. A1 - Salasca, S. A1 - Salmon, T. A1 - Salvador, J. A1 - Samaille, F. A1 - Samain, A. A1 - Santagiustina, A. A1 - Saoutic, B. A1 - Sarazin, Y. A1 - Schild, T. A1 - Schlosser, J. A1 - Schneider, M. A1 - Schneider, K. A1 - Schunke, B. A1 - Schwander, F. A1 - Schwob, J. L. A1 - Sebelin, E. A1 - Segui, J. L. A1 - Seigneur, A. A1 - Shepard, T. A1 - Shigin, P. A1 - Signoret, J. A1 - Simoncini, J. A1 - Simonet, F. A1 - Simonin, A. A1 - Sirinelli, A. A1 - Sledziewski, Z. A1 - Smits, F. A1 - Soler, K. A1 - Sonato, P. G. A1 - Song, S. D. A1 - Sonnendrucker, E. A1 - Sourd, F. A1 - Spitz, P. A1 - Spuig, P. A1 - Stamm, R. A1 - Stephan, Y. A1 - Stirling, W. A1 - Stockel, J. A1 - Stott, P. A1 - Sthal, K. S. A1 - Surle, F. A1 - Svensson, L. A1 - Tachon, J. A1 - Talvard, M. A1 - Tamain, P. A1 - Tavian, L. A1 - Tena, M. A1 - Theis, J. M. A1 - Thomas, C. E. A1 - Thomas, P. A1 - Thonnat, M. A1 - Tobin, S. A1 - Tokar, M. A1 - Tonon, G. A1 - Torossian, A. A1 - Torre, A. A1 - Trainham, R. C. A1 - Travere, J. M. A1 - Tresset, G. A1 - Trier, E. A1 - Truc, A. A1 - Tsitrone, E. A1 - Turck, B. A1 - Turco, F. A1 - Turlur, S. A1 - Uckan, T. A1 - Udintsev, V. A1 - Urguijo, G. A1 - Utzel, N. A1 - Vallet, J. C. A1 - Valter, J. A1 - Van Houtte, D. A1 - Van Rompuy, T. A1 - Vatry, A. A1 - Verga, A. A1 - Vermare, L. A1 - Vezard, D. A1 - Viallet, H. A1 - Villecroze, F. A1 - Villedieu, E. A1 - Villegas, D. A1 - Vincent, E. A1 - Voitsekovitch, I. A1 - von Hellermann, M. A1 - Voslamber, D. A1 - Voyer, D. A1 - Vulliez, K. A1 - Wachter, C. A1 - Wagner, T. A1 - Waller, V. A1 - Wang, G. A1 - Wang, Z. A1 - Watkins, J. A1 - Weisse, J. A1 - White, R. A1 - Wijnands, T. A1 - Witrant, E. A1 - Worms, J. A1 - Xiao, W. A1 - Yu, D. A1 - Zabeo, L. A1 - Zabiego, M. A1 - Zani, L. A1 - Zhuang, G. A1 - Zou, X. L. A1 - Zucchi, E. A1 - Zunino, K. A1 - Zwingmann, W. VL - 56 SN - 1536-1055 UR -