TY - JOUR
T1 - Overview of MAST results
JF - Nuclear Fusion
Y1 - 2015
A1 - Chapman, I.T.
A1 - Adamek, J.
A1 - Akers, R. J.
A1 - Allan, S.
A1 - Appel, L.
A1 - Asunta, O.
A1 - Barnes, M.
A1 - N. Ben Ayed
A1 - Hawke, J.
A1 - Bigelow, T.
A1 - Boeglin, W.
A1 - Bradley, J.
A1 - Brünner, J.
A1 - Cahyna, P.
A1 - Carr, M.
A1 - Caughman, J.
A1 - Cecconello, M.
A1 - Challis, C.
A1 - Chapman, S.
A1 - Chorley, J.
A1 - Colyer, G.
A1 - Conway, N.
A1 - Cooper, W. A.
A1 - Cox, M.
A1 - Crocker, N.
A1 - Crowley, B.
A1 - Cunningham, G.
A1 - Danilov, A.
A1 - Darrow, D.
A1 - Dendy, R.
A1 - Diallo, A.
A1 - Dickinson, D.
A1 - Diem, S.
A1 - Dorland, W.
A1 - Dudson, B.
A1 - Dunai, D.
A1 - Easy, L.
A1 - Elmore, S.
A1 - Field, A.
A1 - Fishpool, G.
A1 - Fox, M.
A1 - Fredrickson, E.
A1 - Freethy, S.
A1 - Garzotti, L.
A1 - Ghim, Y. C.
A1 - Gibson, K.
A1 - Graves, J.
A1 - Gurl, C.
A1 - Guttenfelder, W.
A1 - Ham, C.
A1 - Harrison, J.
A1 - Harting, D.
A1 - Havlickova, E.
A1 - Hawkes, N.
A1 - Hender, T.
A1 - Henderson, S.
A1 - Highcock, E.
A1 - Hillesheim, J.
A1 - Hnat, B.
A1 - Holgate, J.
A1 - Horacek, J.
A1 - Howard, J.
A1 - Huang, B.
A1 - Imada, K.
A1 - Jones, O.
A1 - S. Kaye
A1 - Keeling, D.
A1 - Kirk, A.
A1 - Klimek, I.
A1 - Kocan, M.
A1 - Leggate, H.
A1 - Lilley, M.
A1 - Lipschultz, B.
A1 - Lisgo, S.
A1 - Liu, Y. Q.
A1 - Lloyd, B.
A1 - Lomanowski, B.
A1 - Lupelli, I.
A1 - Maddison, G.
A1 - J. Mailloux
A1 - Martin, R.
A1 - McArdle, G.
A1 - McClements, K.
A1 - McMillan, B.
A1 - Meakins, A.
A1 - Meyer, H.
A1 - Michael, C.
A1 - Militello, F.
A1 - Milnes, J.
A1 - Morris, A. W.
A1 - Motojima, G.
A1 - Muir, D.
A1 - Nardon, E.
A1 - Naulin, V.
A1 - Naylor, G.
A1 - Nielsen, A.
A1 - O'Brien, M.
A1 - O'Gorman, T.
A1 - Ono, Y.
A1 - Oliver, H.
A1 - Pamela, S.
A1 - Pangioni, L.
A1 - Parra, F.
A1 - Patel, A.
A1 - Peebles, W.
A1 - Peng, M.
A1 - Perez, R.
A1 - Pinches, S.
A1 - Piron, L.
A1 - Podesta, M.
A1 - Price, M.
A1 - Reinke, M.
A1 - Ren, Y.
A1 - Roach, C.
A1 - Robinson, J.
A1 - Romanelli, M.
A1 - Rozhansky, V.
A1 - Saarelma, S.
A1 - Sangaroon, S.
A1 - Saveliev, A.
A1 - Scannell, R.
A1 - Schekochihin, A.
A1 - Sharapov, S.
A1 - Sharples, R.
A1 - Shevchenko, V.
A1 - Silburn, S.
A1 - J. Simpson
A1 - Storrs, J.
A1 - Takase, Y.
A1 - Tanabe, H.
A1 - Tanaka, H.
A1 - Taylor, D.
A1 - Taylor, G.
A1 - Thomas, D.
A1 - Thomas-Davies, N.
A1 - Thornton, A.
A1 - Turnyanskiy, M.
A1 - Valovic, M.
A1 - Vann, R.
A1 - Walkden, N.
A1 - Wilson, H.
A1 - Wyk, L. V.
A1 - Yamada, T.
A1 - Zoletnik, S.
A1 - MAST Team
A1 - MAST Upgrade Teams
VL - 55
IS - 10
U1 - FP
U2 - TP
U5 - 9d7b191e90422e8ed8bcf2078b75987f
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 - 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 - 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 -