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8. Real-time measurement and control at JET experiment control

Author

Felton, R., Joffrin, E., Murari, A., Zabeo, L., Sartori, F., Piccolo, F., Farthing, J., Budd, T., Dorling, S., McCullen, P., Harling, J., Dalley, S., Goodyear, A., Stephen, A., Card, P., Bright, M., Lucock, R., Jones, E., Griph, S., Hogben, C., Beldishevski, M., Buckley, M., Davis, J., Young, I., Hemming, O., Wheatley, M., Heesterman, P., Lloyd, G., Walters, M., Bridge, R., Leggate, H., Howell, D., Zastrow, K.-D, Giroud, C., Coffey, I., Hawkes, N., Stamp, M., Barnsley, R., Edlington, T., Guenther, K., Gowers, C., Popovichef, S., Huber, A., Ingesson, C., Mazon, D., Moreau, D., Alves, D., Sousa, J., Riva, M., Barana, O., Bolzonella, T., Valisa, M., Innocente, P., Zerbini, M., Bosak, K., Blum, J., Vitale, E., Crisanti, F., de la Luna, E., and Sanchez, J.

Published
2005
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14. THE JET PRELIMINARY TRITIUM EXPERIMENT

Author

REBUT, P, ADAMS, J, ALPER, B, ALTMANN, H, ANDERSEN, A, ANDREW, P, ALIARSHAD, S, BAILEY, W, BALET, B, BARABASCHI, P, BARANOV, Y, BARKER, P, BARNSLEY, R, BARONIAN, M, BARTLETT, D, BELL, A, BENALI, G, BERTOLI, P, BERTOLINI, E, BHATNAGAR, V, BICKLEY, A, BOND, D, BONICELLI, T, BOOTH, S, BOSIA, G, BOTMAN, M, BOUCHER, D, BOUCQUEY, P, BRANDON, M, BREGER, P, BRELEN, H, BREWERTON, W, BRINKSCHULTE, H, BROWN, T, BRUSATI, M, BUDD, T, BURES, M, BURTON, P, BUSINARO, T, BUTCHER, P, BUTTGEREIT, H, CALDWELLNICHOLS, C, CAMPBELL, D, CAMPLING, D, CARD, P, CELENTANO, G, CHALLIS, C, CHANKIN, A, CHERUBINI, A, CHIRON, D, CHRISTIANSEN, J, CHUILON, P, CLAESEN, R, CLEMENT, S, CLIPSHAM, E, COAD, J, COFFEY, I, COLTON, A, COMISKEY, M, CONROY, S, COOKE, M, COOPER, S, CORDEY, J, CORE, W, CORRIGAN, G, CORTI, S, COSTLEY, A, COTTRELL, G, COX, M, CRAWLEY, P, DACOSTA, O, DAVIES, N, DAVIES, S, DEBLANK, H, DEESCH, H, DEKOCK, L, DEKSNIS, E, DELIYANAKUS, N, DENNEHINNOV, G, DESCHAMPS, G, DICKSON, W, DIETZ, K, DINES, A, DMITRENKO, S, DMITRIEVA, M, DOBBING, J, DOLGETTA, N, DORLING, S, DOYLE, P, DUCHS, D, DUQUENOY, H, EDWARDS, A, EHRENBERG, J, EKEDAHL, A, ELEVANT, T, ERENTS, S, ERIKSSON, L, FAJEMIROKUN, H, FALTER, H, FREILING, J, FROGER, C, FROISSARD, P, FULLARD, K, GADEBERG, M, GALETSAS, A, GALBIATI, L, GAMBIER, D, GARRIBBA, M, GAZE, P, GIANNELLA, R, GIBSON, A, GILL, R, GIRARD, A, GONDHALEKAR, A, GOODALL, D, GORMEZANO, C, GOTTARDI, N, GOWERS, C, GREEN, B, HAANGE, R, HAIGH, A, HANCOCK, C, HARBOUR, P, HAWKES, N, HAYNES, P, HEMMERICH, J, HENDER, T, HOEKZEMA, J, HORTON, L, HOW, J, HOWARTH, P, HUART, M, HUGHES, T, HUGUET, M, HURD, F, IDA, K, INGRAM, B, IRVING, M, JACQUINOT, J, JAECKEL, H, JAEGER, J, JANESCHITZ, G, JANKOWICZ, Z, JARVIS, O, JENSEN, F, JONES, E, JONES, L, JONES, T, JUNGER, J, JUNIQUE, F, KAYE, A, KEEN, B, KEILHACKER, M, KERNER, W, KIDD, N, KONIG, R, KONSTANTELLOS, A, KUPSCHUS, P, LASSER, R, LAST, J, LAUNDY, B, LAUROTARONI, L, LAWSON, K, LENNHOLM, M, LINGERTAT, J, LITUNOVSKI, R, LOARTE, A, LOBEL, R, LOMAS, P, LOUGHLIN, M, LOWRY, C, MAAS, A, MACKLIN, B, MAGGI, C, MAGYAR, G, MARCHESE, V, MARCUS, F, MART, J, MARTIN, D, MARTIN, E, MARTINSOLIS, R, MASSMANN, P, MATTHEWS, G, MCBRYAN, H, MCCRACKEN, G, MERIGUET, P, MIELE, P, MILLS, S, MILLWARD, P, MINARDI, E, MOHANTI, R, MONDINO, P, MONTVAI, A, MORGAN, P, MORSI, H, MURPHY, G, NAVE, F, NEUDATCHIN, S, NEWBERT, G, NEWMAN, M, NIELSEN, P, NOLL, P, OBERT, W, OBRIEN, D, OROURKE, J, OSTROM, R, OTTAVIANI, M, PAPASTERGIOU, S, PASINI, D, PATEL, B, PEACOCK, A, PEACOCK, N, PEARCE, R, PEARSON, D, PEPEDESILVA, R, PERINIC, G, PERRY, C, PICK, M, PLANCOULAINE, J, POFFE, J, POHLCHEN, R, PORCELLI, F, PORTE, L, PRENTICE, R, PUPPIN, S, PUTVINSKII, S, RADFORD, G, RAIMONDI, T, RAMOSDEANDRADE, M, RAPISARDA, M, REICHLE, R, RICHARDS, S, RIGHI, E, RIMINI, F, ROLFE, A, ROSS, R, ROSSI, L, RUSS, R, SACK, H, SADLER, G, SAIBENE, G, SALANAVE, J, SANAZZARO, G, SANTAGIUSTINA, A, SARTORI, R, SBORCHIA, C, SCHILD, P, SCHMID, M, SCHMIDT, G, SCHROEPF, H, SCHUNKE, B, SCOTT, S, SIBLEY, A, SIMONINI, R, SIPS, A, SMEULDERS, P, SMITH, R, STAMP, M, STANGEBY, P, START, D, STEED, C, STORK, D, STOTT, P, STUBBERFIELD, P, SUMMERS, D, SUMMERS, H, SVENSSON, L, TAGLE, J, TANGA, A, TARONI, A, TERELLA, C, TESINI, A, THOMAS, P, THOMPSON, E, THOMSEN, K, TREVALION, P, TUBBING, B, TIBONE, F, VANDERBEKEN, H, VLASES, G, VONHELLERMANN, M, WADE, T, WALKER, C, WARD, D, WATKINS, M, WATSON, M, WEBER, S, WESSON, J, WIJNANDS, T, WILKS, J, WILSON, D, WINKEL, T, WOLF, R, WONG, D, WOODWARD, C, WYKES, M, YOUNG, I, ZANNELLI, L, ZOLFAGHARI, A, ZULLO, G, and ZWINGMANN, W

Subjects
inorganic chemicals, Jet (fluid), Tokamak, Materials science, Lawson criterion, Joint European Torus, Plasma, Fusion power, Condensed Matter Physics, law.invention, Nuclear physics, Nuclear Energy and Engineering, Deuterium, law, cardiovascular system, Tritium
Abstract

The first tokamak discharges with deuterium-tritium mixtures have been carried out in the Joint European Torus (JET). The main objectives were to produce more than IMW of fusion power in a controlled way, to determine tritium retention in torus systems and to establish effective means of tritium removal. The experiments were undertaken within limits imposed by restrictions on vessel activation and tritium usage. Deuterium plasmas were heated by high power deuterium neutral beams from fourteen sources and fuelled by two neural beam sources injecting tritium. In the best (D-T discharge), the tritium concentration was about 11% at peak performance, when total neutron emission rate was 6.0*1017 s-1, with 1.7 MW of fusion power. The fusion amplification factor QDT was 0.15. With optimum tritium concentration, this pulse would have produced a fusion power approximately=5 MW and nominal QDT=0.46. The same extrapolation for the best pure deuterium discharge gives about 11 MW and a nominal QDT=1.14. Techniques for introducing, tracking, monitoring and recovering tritium were highly effective.

Published
2016

20. JET experiments to assess the clamping of the fast ion energy distribution during ICRF heating due to finite Larmor radius effects

Author

Salmi, A., Mantsinen, M. J., Beaumont, P., de Vries, P., Eriksson, L. G., Gowers, C., Helander, P., Laxaback, M., Noterdaeme, J. M., Testa, D., and EFDA JET Contributors

Subjects
Physics::Plasma Physics, JET, Physics::Space Physics
Abstract

Experiments have been performed on the JET tokamak with 2nd harmonic ion cyclotron resonance heating (ICRH) of hydrogen in deuterium plasmas to assess the role of finite Larmor radius (FLR) effects on the resonant ion distribution function. More specifically, the clamping of high-energy resonant particle distribution due to weak wave-particle interaction at high energy is studied. The distributions of ICRH heated hydrogen ions have been measured with a high-energy neutral particle analyser in the range of 0.29-1.1 MeV. By changing the electron density the energy E*, around which the wave-particle interaction becomes weak, is varied. The dependence of the ion distribution on E* is experimentally observed for a number of discharges and FLR effects are clearly seen to affect the high energy tail shape. Experiments have been analysed with the combination of ICRH modelling codes PION and FIDO, including FLR effects, and good agreement with measurements have been found.

Published
2006

21. Proton-triton nuclear reaction in ICRF heated plasmas in JET

Author

Santala, M. I. K., Mantsinen, M. J., Bertalot, L., Conroy, S., Kiptily, V., Popovichev, S., Salmi, A., Testa, D., Baranov, Yu., Beaumont, P., Belo, P., Brzozowski, J., Cecconello, M., de Baar, M., de Vries, P., Gowers, C., Noterdaeme, J.-M., Schlatter, C., Sharapov, S., and JET-EFDA Contributors

Published
2006

22. Proton-triton nuclear reaction in ICRF heated plasmas in JET

Author

Santala, M.I. K., Mantsinen, M.J., Bertalot, L., Conroy, S., Kiptily, V., Popovichev, S., Salmi, A., Testa, D., Baranov, Y., Beaumont, P., Belo, P., Brzozowski, J., Cecconello, M., de Baar, M., de Vries, P., Gowers, C., Noterdaeme, J.M., Schlatter, C., Sharapov, S., and JET-EFDA Contributors

Subjects
inorganic chemicals, Physics::Plasma Physics, JET, Nuclear Theory, technology, industry, and agriculture, Nuclear Experiment
Abstract

Fast protons can react with tritons in an endothermic nuclear reaction which can act as a source of neutrons in magnetically confined fusion plasmas. We have performed an experiment to systematically study this reaction in low tritium concentration (approximate to 1%) plasmas in the Joint European Torus. A linear dependence is found between excess neutron rate and tritium concentration when the DT fusion rate is low. We discuss the properties of the neutron emission, including anisotropy, from the proton-triton reaction in a fusion reactor environment and derive simple models for the calculation of the neutron yield from this reaction in terms of tritium density, fast ion temperature and fast ion energy content.

Published
2006

24. Expanding the operating space of ICRF on JET with a view to ITER

Author

Lamalle P.U., Mantsinen M.J., Noterdaeme J.M., Alper B., Tardocchi M., Beaumont P., Bertalot L., Blackman T., Bobkov VI.V., Bonheure G., Brzozowski J., Castaldo C., Conroy S., de Baar M., de la Luna E., de Vries P., Durodiè F., Ericsson G., Erik L.G., Gowers C., R. Felton R., Heikkinen J., Hellsten T., Kiptily V., Lawson K., Laxåback M., Lerche E., Lomas P., Lyssoivan A., Mayoral M.L., Meo F., Mironov M., Monakhov I., Nunes I., Piazza G., Popovichev S., Salmi A., Santala M.I.K., Sharapov S., Tala T., Van Eester D., Weyssow B., JET EFDA contributors, and JET EFDA Contributors

Subjects
Nuclear and High Energy Physics, Jet (fluid), Materials science, fusion reactors, Magnetic confinement fusion, ion cyclotron resonance frequency, Plasma, Fusion power, Condensed Matter Physics, fusion energy, Dipole, Physics::Plasma Physics, JET, ITER, Electron temperature, Neutron, Atomic physics, Ion cyclotron resonance, plasma
Abstract

This paper reports on ITER-relevant ion cyclotron resonance frequency (ICRF) physics investigated on JET in 2003 and early 2004. Minority heating of helium three in hydrogen plasmas—(3He)H—was systematically explored by varying the 3He concentration and the toroidal phasing of the antenna arrays. The best heating performance (a maximum electron temperature of 6.2 keV with 5 MW of ICRF power) was obtained with a preferential wave launch in the direction of the plasma current. A clear experimental demonstration was made of the sharp and reproducible transition to the mode conversion heating regime when the 3He concentration increased above ~2%. In the latter regime the best heating performance (a maximum electron temperature of 8 keV with 5 MW of ICRF power) was achieved with dipole array phasing, i.e. a symmetric antenna power spectrum. Minority heating of deuterium in hydrogen plasmas—(D)H—was also investigated but was found inaccessible because this scenario is too sensitive to impurity ions with Z/A = 1/2 such as C6+, small amounts of which directly lead into the mode conversion regime. Minority heating of up to 3% of tritium in deuterium plasmas was systematically investigated during the JET trace tritium experimental campaign (TTE). This required operating JET at its highest possible magnetic field (3.9 to 4 T) and the ICRF system at its lowest frequency (23 MHz). The interest of this scenario for ICRF heating at these low concentrations and its efficiency at boosting the suprathermal neutron yield were confirmed, and the measured neutron and gammay ray spectra permit interesting comparisons with advanced ICRF code simulations. Investigations of finite Larmor radius effects on the RF-induced high-energy tails during second harmonic (ω = 2ωc) heating of a hydrogen minority in D plasmas clearly demonstrated a strong decrease in the RF diffusion coefficient at proton energies ~ 1 MeV, in agreement with theoretical expectations. Fast wave heating and current drive experiments in deuterium plasmas showed effective direct electron heating with dipole phasing of the antennas, but only small changes of the central plasma current density were observed with the directive phasings, in particular at low single pass damping. New investigations of the heating efficiency of ICRF antennas confirmed its strong dependence on the parallel wavenumber spectrum. Advances in topics of a more technological nature are also summarized: ELM studies using fast RF measurements, the successful experimental demonstration of a new ELM-tolerant antenna matching scheme and technical enhancements planned on the JET ICRF system for 2006, they being equally strongly driven by the preparation for ITER.

Published
2006
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25. Fast ion distributions driven by polychromatic ICRF waves on JET

Author

Mantsinen, M.J., Kiptily, V., Laxaback, M., Salmi, A., Baranov, Y., Barnsley, R., Beaumont, P., Conroy, S., de Vries, P., Giroud, C., Gowers, C., Hellsten, T., Ingesson, L.C., Johnson, T., Leggate, H., Mayoral, M.L., Monakhov, I., Noterdaeme, J.M., Podda, S., Sharapov, S., Tuccillo, A.A., and Van Eester, D.

Published
2005

26. Recent developments of ECE Diagnostics at JET

Author

de la Luna E., Blanchard P., Bruschi A., Centioli C., Conway G., Felton R., Fessey J., Gowers C., Joffrin E., Mazon D., Murari A., Nowak S., Riva M., Simonetto A., Sozzi C., Sanchez J., Zerbini M., and JET-EFDA contributors

Subjects
___
Abstract

In this paper, the recent developments in the JET ECE diagnostic system will be described and illustrated with some recent results, with an emphasis on issues related with calibration stability, high-Te plasmas and ITB studies. Some of these issues will be discussed in the context of ITER.

Published
2005

27. High resolution Thomson scattering for Joint European Torus (JET)

Author

Pasqualotto, R., Nielsen, P., Gowers, C., Beurskens, M., Kempenaars, M., Carlstrom, T., and Johnson, D.

Abstract

A Thomson scattering system is being developed for Joint European Torus with 15 mm spatial resolution and a foreseen accuracy for temperature better than 15% at a density of 10(19) m(-3). This resolution is required at the internal transport barrier and edge pedestal and it can not be fully achieved with the present light detection and ranging systems. The laser for this system is Nd:YAG, 5 Joule, 20 Hz. Scattering volumes from R=2.9 m to R=3.9 m are imaged onto 1 mm diameter fibers, with F/25 collection aperture. Two fibers are used per scattering volume. Using optical delay lines, three scattering volumes are combined in each of the 21 filter polychromators. The signals are recorded with transient digitizers, which allow the combined time delayed signals to be resolved. Knowledge of the time delay between signals allows the use of correlation techniques in determining signal levels. The ac output of the amplifier is used, which tolerates a higher level of background signal without affecting dynamic range. The noise resulting from plasma light is determined directly. (C) 2004 American Institute of Physics.

Published
2004

29. Analysis of Plasma Edge Profiles at JET

Author

Beurskens, M., Giovannozzi, E., Gunn, J., Andrew, Y., Brix, M., Chareau, J., Erents, K., Gowers, C., Günther, K., Jachmich, S., Kallenbach, A., Korotkov, A., de la Luna, E., Morgan, P., Prentice, R., Proschek, M., Saibene, G., Suttrop, W., Travere, J., Tribaldos, V., Zerbini, M., and EFDA-JET Work Programme Collaborators

Published
2001

30. Extreme shear reversal in JET discharges

Author

Hawkes, N., Stratton, B., Baranov, Y., Bolzonella, T., Challis, C., Cortes, S., DeAngelis, R., Gowers, C., Hennequin, P., Joffrin, E., Lotte, Ph, Mailloux, J., Mazon, D., Parail, V., Prentice, R., Rachlew, E., Solano, E., and Tala, Tuomas

Published
2001

31. Use of lower hybrid current drive and heating in optimised shear plasmas in JET

Author

Mailloux, J., Alper, B., Baranov, Y., Barbato, E., Becoulet, A., Cardinali, A., Castaldo, C., Cesario, R., Challis, C., Crisanti, F., de Baar, M., de Vries, P., Ekedahl, A., Gowers, C., Hawkes, N., Imbeaux, F., Joffrin, E., Litaudon, X., Mazon, D., Pericoli, V., Prentice, R., Sarazin, Y., Stratton, B., Tuccillo, A., Tala, Tuomas, and Zastrow, K.-D.

Published
2001

32. Edge transport barrier in JET hot-ion H-modes

Author

Guo, H. Y., Parail, V., Keilhacker, M., König, R. W. T., Lomas, P., Maas, A. C., Macus, F., Matthews, C. F., Nave, F., Rimini, F., Smith, R., Stamp, M. F., Andrew, P., Taroni, A., Thomas, P., Zastrow, S. A., Balet, B., Conway, C. D., DeEsch, B., Gowers, C. W., von Hellermann, M., Huysmans, G., and Jones, T. T. C.

Subjects
ddc:530
Abstract

The effects of changing beam and plasma species on the edge transport barrier are investigated for ELM-free hot ion H mode discharges from the recent DT experiments on JET. The measured pressure at the top of the pedestal is higher for mixed deuterium and tritium and pure tritium plasmas over and above the level measured in pure deuterium plasmas at the same heating power. The pedestal pressure increases with beam tritium concentration for mixed deuterium-tritium beam injection into deuterium plasmas where the measured edge tritium concentration remains low. Alpha heating plays a significant role in the core of such plasmas, and the possible impact on the edge is discussed together with possible direct isotopic effects. Heuristic models for the transport barrier width are proposed, and used to explore a wider range of edge measurements including full power DD and DT pulses. This analysis supports the plasma current and mass dependence for a barrier width set by the orbit loss of either thermal or fast ions, though it does not unambiguously distinguish between them. The fast ion hypothesis could well account for some of the JET observations, though more theoretical work and direct experimental measurement would be required to confirm this. An ad hoc model for the power loss through the separatrix, P(loss)proportional-to-n(edge)(2)Z(eff,edge)I(p)(-1), is proposed based on neoclassical theory, a ballooning limit to the edge gradient and a barrier width set by the poloidal ion gyroradius. Such a model is compared with experimental data from JET. In particular, the model ascribes the systematic difference in loss power between the Mark I and Mark II diverters to the change in the measured Z(eff). This change in Z(eff) is consistent with the observed change in impurity production, which is described in some detail, together with a possible explanation provided by the temperature dependence of chemical sputtering.

Published
2000

34. Optimised Shear Scenario Development on JET towards Steady-State

Author

Söldner, F., Alper, B., Baranov, Y., Bickley, A., Borba, D., Challis, C., Conway, G., Cottrell, G., de Benedetti, M., Deliyanakis, N., Gormezano, C., Gowers, C., Greenfield, C., Hawkes, N., Hender, T., Huysmans, G., Joffrin, E., Jones, T., Lang, P., Litaudon, X., Lomas, P., Maas, A., Mailloux, J., Mantsinen, M., Nave, F., Parail, V., Rimini, F., Schunke, B., Sips, A., Smeulders, P., Stamp, M., Strait, E., Tala, T., von Hellermann, M., Ward, D., and Zastrow, K.

Published
1999

35. High DT Fusion Performance in ELM-Free H-Modes in JET

Author

Rimini, F., Andrew, P., Balet, B., Budny, R., Bull, J., Deliyanakis, N., De Esch, H., Eriksson, L., Giannella, R., Gowers, C., Guo, H., Hender, T., Huysmans, G., Jones, T., Keilhacker, M., Koenig, R., Lennholm, M., Lomas, P., Loughlin, M., Maas, A., Mantsinen, M., Marcus, F., Nave, F., Parail, V., Strachan, J., Taroni, A., Thomas, P., and Zastrow, K.

Published
1998

36. DT Mixture Control with Neutral Beam Fuelling and Importance of Particle recycling and Isotope Exchange in the JET ELM-Free-H-Mode

Author

Jones, T., Pavlo, P., Andrew, P., Alper, B., Balet, B., Cherubini, A., Christiansen, J., Crisanti, F., De Angelis, R., De Esch, H., Deliyanakis, N., De Luca, F., Erba, M., Edwards, A., Eriksson, L., Frewin, C., Galli, P., Gowers, C., Gorini, G., Guenther, K., Guo, H., Hawkes, N., Hender, T., Huysmans, G., Koenig, R., Lawson, K., Lingertat, J., Mantsinen, M., McCormick, K., Maas, A., Marcus, F., Nave, F., Parail, V., Porte, L., Rimini, F., Schunke, B., Smeulders, P., Taroni, A., Thomas, P., Saibene, G., and Zastrow, K.

Published
1998

37. Expanding the operating space of ICRF on JET with a view to ITER

Author

Lamalle, P.U, Mantsinen, M.J, Noterdaeme, J-M, Alper, B, Beaumont, P, Bertalot, L, Blackman, T, Bobkov, Vl.V, Bonheure, G, Brzozowski, J, Castaldo, C, Conroy, S, de Baar, M, de la Luna, E, de Vries, P, Durodi, F, Ericsson, G, Eriksson, L G, Gowers, C, Felton, R, Heikkinen, J, Hellesten, T, Kiptily, V, Lawson, K, Laxåback, M, Lerche, E, Lomas, P, Lyssoivan, A, Mayoral, M-L, Meo, F, Miranov, M, Monakhov, I, Nunes, I, Piazza, G, Popovichev, S, Salmi, A, Santala, MIK, Sharapov, S, Tala, T, Tardocchi, M, Van Eester, D, Weyssow, B, Lamalle, P.U, Mantsinen, M.J, Noterdaeme, J-M, Alper, B, Beaumont, P, Bertalot, L, Blackman, T, Bobkov, Vl.V, Bonheure, G, Brzozowski, J, Castaldo, C, Conroy, S, de Baar, M, de la Luna, E, de Vries, P, Durodi, F, Ericsson, G, Eriksson, L G, Gowers, C, Felton, R, Heikkinen, J, Hellesten, T, Kiptily, V, Lawson, K, Laxåback, M, Lerche, E, Lomas, P, Lyssoivan, A, Mayoral, M-L, Meo, F, Miranov, M, Monakhov, I, Nunes, I, Piazza, G, Popovichev, S, Salmi, A, Santala, MIK, Sharapov, S, Tala, T, Tardocchi, M, Van Eester, D, and Weyssow, B

Abstract

Mercury (Hg) has been used for millennia in many applications, primarily in artisanal mining and as an electrode in the chlor–alkali industry. It is anthropogenically emitted as a pollutant from coal fired power plants and naturally emitted, primarily from volcanoes. Its unique chemical characteristics enable global atmospheric transport and it is deposited after various processes, ultimately ending up in one of its final sinks, such as incorporated into deep sediment or bioaccumulated, primarily in the marine environment. All forms of Hg have been established as toxic, and there have been no noted biological benefits from the metal. Throughout time, there have been notable incidents of Hg intoxication documented, and the negative health effects have been documented to those chronically or acutely exposed. Today, exposure to Hg is largely diet or occupationally dependent, however, many are exposed to Hg from their amalgam fillings. This paper puts a tentative monetary value on Hg polluted food sources in the Arctic, where local, significant pollution sources are limited, and relates this to costs for strategies avoiding Hg pollution and to remediation costs of contaminated sites in Sweden and Japan. The case studies are compiled to help policy makers and the public to evaluate whether the benefits to the global environment from banning Hg and limiting its initial emission outweigh the benefits from its continued use or lack of control of Hg emissions. The cases we studied are relevant for point pollution sources globally and their remediation costs ranged between 2500 and 1.1 million US$ kg−1 Hg isolated from the biosphere. Therefore, regulations discontinuing mercury uses combined with extensive flue gas cleaning for all power plants and waste incinerators is cost effective.

Published
2006

38. Expanding the operating space of ICRF on JET with a view to ITER

Author

Lamalle, P. U., Mantsinen, M. J., Noterdaeme, J. M., Alper, B., Beaumont, P., Bertalot, L., Blackman, T., Bobkov, V. V., Bonheure, G., Brzozowski, Jerzy H., Castaldo, C., Conroy, S., de Baar, M., de la Luna, E., de Vries, P., Durodie, F., Ericsson, G., Eriksson, L. G., Gowers, C., Felton, R., Heikkinen, J., Hellsten, Torbjörn A. K., Kiptily, V., Lawson, K., Laxåback, Martin, Lerche, E., Lomas, P., Lyssoivan, A., Mayoral, M. L., Meo, F., Mironov, M., Monakhov, I., Nunes, I., Piazza, G., Popovichev, S., Salmi, A., Santala, M. I. K., Sharapov, S., Tala, T., Tardocchi, M., Van Eester, D., Weyssow, B., Lamalle, P. U., Mantsinen, M. J., Noterdaeme, J. M., Alper, B., Beaumont, P., Bertalot, L., Blackman, T., Bobkov, V. V., Bonheure, G., Brzozowski, Jerzy H., Castaldo, C., Conroy, S., de Baar, M., de la Luna, E., de Vries, P., Durodie, F., Ericsson, G., Eriksson, L. G., Gowers, C., Felton, R., Heikkinen, J., Hellsten, Torbjörn A. K., Kiptily, V., Lawson, K., Laxåback, Martin, Lerche, E., Lomas, P., Lyssoivan, A., Mayoral, M. L., Meo, F., Mironov, M., Monakhov, I., Nunes, I., Piazza, G., Popovichev, S., Salmi, A., Santala, M. I. K., Sharapov, S., Tala, T., Tardocchi, M., Van Eester, D., and Weyssow, B.

Abstract

This paper reports on ITER-relevant ion cyclotron resonance frequency (ICRF) physics investigated on JET in 2003 and early 2004. Minority heating of helium three in hydrogen plasmas-(He-3)H-was systematically explored by varying the 3 He concentration and the toroidal phasing of the antenna arrays. The best heating performance (a maximum electron temperature of 6.2 keV with 5 MW of ICRF power) was obtained with a preferential wave launch in the direction of the plasma current. A clear experimental demonstration was made of the sharp and reproducible transition to the mode conversion heating regime when the 3 He concentration increased above similar to 2%. In the latter regime the best heating performance (a maximum electron temperature of 8 keV with 5 MW of ICRF power) was achieved with dipole array phasing, i.e. a symmetric antenna power spectrum. Minority heating of deuterium in hydrogen plasmas-(D)H-was also investigated but was found inaccessible because this scenario is too sensitive to impurity ions with Z/A = 1/2 such as C6+, small amounts of which directly lead into the mode conversion regime. Minority heating of up to 3% of tritium in deuterium plasmas was systematically investigated during the JET trace tritium experimental campaign (TTE). This required operating JET at its highest possible magnetic field (3.9 to 4 T) and the ICRF system at its lowest frequency (23 MHz). The interest of this scenario for ICRF heating at these low concentrations and its efficiency at boosting the suprathermal neutron yield were confirmed, and the measured neutron and gammay ray spectra permit interesting comparisons with advanced ICRF code simulations. Investigations of finite Larmor radius effects on the RF-induced high-energy tails during second harmonic (omega = 2 omega(c)) heating of a hydrogen minority in D plasmas clearly demonstrated a strong decrease in the RF diffusion coefficient at proton energies similar to 1 MeV in agreement with theoretical expectations. Fast, QC 20100525 QC 20111003. Conference: 20th IAEA Fusion Energy Conference. Vilamoura, PORTUGAL. NOV 01-06, 2004

Published
2006
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39. Hydrogen plasmas with ICRF inverted minority and mode conversion heating regimes in the JET tokamak

Author

Mayoral, M. L., Lamalle, P. U., Van Eester, D., Lerche, E. A., Beaumont, P., De La Luna, E., De Vries, P., Gowers, C., Felton, R., Harling, J., Kiptily, V., Lawson, K., Laxåback, Martin, Lomas, P., Mantsinen, M. J., Meo, F., Noterdaeme, J. M., Nunes, I., Piazza, G., Santala, M., Mayoral, M. L., Lamalle, P. U., Van Eester, D., Lerche, E. A., Beaumont, P., De La Luna, E., De Vries, P., Gowers, C., Felton, R., Harling, J., Kiptily, V., Lawson, K., Laxåback, Martin, Lomas, P., Mantsinen, M. J., Meo, F., Noterdaeme, J. M., Nunes, I., Piazza, G., and Santala, M.

Abstract

During the initial operation of the International Thermonuclear Experimental Reactor (ITER), it is envisaged that activation will be minimized by using hydrogen (H) plasmas where the reference ion cyclotron resonance frequency (ICRF) heating scenarios rely on minority species such as helium (He-3) or deuterium (D). This paper firstly describes experiments dedicated to the study of He-3 heating in H plasmas with a sequence of discharges in which 5 MW of ICRF power was reliably coupled and the He-3 concentration, controlled in real-time, was varied from below 1% up to 10%. The minority heating (MH) regime was observed at low concentrations (up to 2%). Energetic tails in the He-3 ion distributions were observed with effective temperatures up to 300 keV and bulk electron temperatures up to 6 keV. At around 2%, a sudden transition was reproducibly observed to the mode conversion regime, in which the ICRF fast wave couples to short wavelength modes, leading to efficient direct electron heating and bulk electron temperatures up to 8 keV. Secondly, experiments performed to study D minority ion heating in H plasmas are presented. This MH scheme proved much more difficult since modest quantities of carbon, QC 20100525

Published
2006
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40. Fast ion distributions driven by polychromatic ICRF waves on JET

Author

Mantsinen, M. J., Kiptily, V., Laxåback, Martin, Salmi, A., Baranov, Y., Barnsley, R., Beaumont, P., Conroy, S., de Vries, P., Giroud, C., Gowers, C., Hellsten, Torbjörn A. K., Ingesson, L. C., Johnson, Thomas J., Leggate, H., Mayoral, M. L., Monakhov, I., Noterdaeme, J. M., Podda, S., Sharapov, S., Tuccillo, A. A., Van Eester, D., Mantsinen, M. J., Kiptily, V., Laxåback, Martin, Salmi, A., Baranov, Y., Barnsley, R., Beaumont, P., Conroy, S., de Vries, P., Giroud, C., Gowers, C., Hellsten, Torbjörn A. K., Ingesson, L. C., Johnson, Thomas J., Leggate, H., Mayoral, M. L., Monakhov, I., Noterdaeme, J. M., Podda, S., Sharapov, S., Tuccillo, A. A., and Van Eester, D.

Abstract

Experiments have been carried out on the JET tokamak to investigate fast He-3 and hydrogen minority ion populations accelerated by ion cyclotron range of frequencies (ICRF) waves launched with multiple frequencies (i.e. up to four frequencies separated by up to approximate to 15%). This 'polychromatic' heating is compared with single-frequency, 'monochromatic', ICRF heating of reference discharges with similar power levels. Information on the fast ion populations is provided by two-dimensional gamma-ray emission tomography and the measurements are compared with numerical modelling. Polychromatic heating with resonances in the plasma centre (R-res approximate to R-0) and on the low magnetic-field side (LFS) (R-res > R-0) is found to produce predominantly high-energy standard trapped ions, while resonances on the high magnetic-field side (R-res < R-0) increase the fraction of high-energy passing ions. Monochromatic heating with a central resonance produces stronger gamma-ray emission with the maximum emission in the midplane close to, and on the LFS of, the resonance, in agreement with the calculated radial distribution of fast ion orbits. Both the fast ion tail temperature and energy content are found to be lower with polychromatic waves. Polychromatic ICRF heating has the advantage of producing smaller-amplitude and shorter-period sawteeth, consistent with a lower fast ion pressure inside the q = 1 surface, and higher ion to electron temperature ratios., QC 20100525

Published
2005
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41. ICRF heating for the non-activated phase of ITER : From inverted minority to mode conversion regime

Author

Mayoral, M L, Lamalle, P U, Van Eester, D, Beaumont, P, De La Luna, E, De Vries, P, Gowers, C, Felton, R, Harling, J, Kiptily, V, Lawson, K, Laxåback, Martin, Lerche, E, Lomas, P, Mantsinen, M J, Meo, F, Noterdaeme, J M, Nunes, I, Piazza, G, Santala, M, Mayoral, M L, Lamalle, P U, Van Eester, D, Beaumont, P, De La Luna, E, De Vries, P, Gowers, C, Felton, R, Harling, J, Kiptily, V, Lawson, K, Laxåback, Martin, Lerche, E, Lomas, P, Mantsinen, M J, Meo, F, Noterdaeme, J M, Nunes, I, Piazza, G, and Santala, M

Abstract

In the initial phase of ITER H plasmas will be used in order to avoid activating the machine. The reference ICRF heating scenarios rely on minority species such as Helium (3 He) or deuterium (D). These schemes' distinctive feature comes from the presence of the fast magnetosonic wave ion-ion hybrid resonance/cut-off pair, between the antennas and the minority cyclotron layer. In order to document these unusual heating schemes, ICRF experiments were carried out recently on JET. First, the use of He-3 ions in H plasmas was investigated with a sequence of discharges in which 5 MW of ICRF power was coupled to the plasma and the 3 He concentration was varied from below 1% up to 10%. The inverted minority heating regime was observed at low concentrations (up to similar to 2%). Energetic tails in the 3 He distribution were observed with effective temperatures up to 300 keV and central electron temperatures up to 6 keV. At around 2%, a sudden transition was reproducibly observed to the mode conversion regime, in which the ICRF fast wave couples to short wavelength modes, leading to efficient direct electron heating and central electron temperature up to 8 keV. All these experiments systematically used power modulation techniques to assess the radial profiles of the wave absorption by the electrons. Secondly, experiments to study the ICRF heating of D minority ions in H were performed. This heating scheme proved much more difficult since modest quantities of C6+ impurity, which has the same Z/A ratio than die D minority ions, led us directly into the mode conversion regime. This effect preventing any absorption by D ions at minority cyclotron layer, could make die (D)H scenario not suitable for the non-active phase of ITER., QC 20101119

Published
2005

42. Localized bulk electron heating with ICRF mode conversion in the JET tokamak

Author

Mantsinen, M. J., Mayoral, M. L., Van Eester, D., Alper, B., Barnsley, R., Beaumont, P., Bucalossi, J., Coffey, I., Conroy, S., de Baar, M., de Vries, P., Erents, K., Figueiredo, A., Gondhalekar, A., Gowers, C., Hellsten, Torbjörn A. K., Joffrin, E., Kiptily, V., Lamalle, P. U., Lawson, K., Lyssoivan, A., Mailloux, J., Mantica, P., Meo, F., Milani, F., Monakhov, I., Murari, A., Nguyen, F., Noterdaeme, J. M., Ongena, J., Petrov, Y., Rachlew, Elisabeth, Riccardo, V., Righi, E., Rimini, F., Stamp, M., Tuccillo, A. A., Zastrow, K. D., Zerbini, M., Mantsinen, M. J., Mayoral, M. L., Van Eester, D., Alper, B., Barnsley, R., Beaumont, P., Bucalossi, J., Coffey, I., Conroy, S., de Baar, M., de Vries, P., Erents, K., Figueiredo, A., Gondhalekar, A., Gowers, C., Hellsten, Torbjörn A. K., Joffrin, E., Kiptily, V., Lamalle, P. U., Lawson, K., Lyssoivan, A., Mailloux, J., Mantica, P., Meo, F., Milani, F., Monakhov, I., Murari, A., Nguyen, F., Noterdaeme, J. M., Ongena, J., Petrov, Y., Rachlew, Elisabeth, Riccardo, V., Righi, E., Rimini, F., Stamp, M., Tuccillo, A. A., Zastrow, K. D., and Zerbini, M.

Abstract

Ion cyclotron resonance frequencies (ICRF) mode conversion has been developed for localized on-axis and off-axis bulk electron heating on the JET tokamak. The fast magnetosonic waves launched from the low-field side ICRF antennas are mode-converted to short-wavelength waves on the high-field side of the He-3 ion cyclotron resonance layer in D and He-4 plasmas and subsequently damped on the bulk electrons. The resulting electron power deposition, measured using ICRF power modulation, is narrow with a typical full-width at half-maximum of approximate to30 cm (i.e. about 30% of the minor radius) and the total deposited power to electrons comprises at least up to 80% of the applied ICRF power. The ICRF mode conversion power deposition has been kept constant using He-3 bleed throughout the ICRF phase with a typical duration of 4-6 s, i.e. 15-40 energy confinement times. Using waves propagating in the counter-current direction minimizes competing ion damping in the presence of co-injected deuterium beam ions., QC 20100525

Published
2004
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43. Localized bulk electron heating with ICRF mode conversion in the JET tokamak

Author

Mantsinen, M.J., Mayoral, M.-L., Eester, D. Van, Alper, B., Barnsley, R., Beaumont, P., Bucalossi, J., Coffey, I., Conroy, S., Baar, M. de, Vries, P. de, Erents, K., Figueiredo, A., Bondhalekar, A., Gowers, C., Hellsten, T., Joffrin, E., Kiptily, V., Lamalle, P.U., Lawson, K., Lyssoivan, A., Mailloux, J., Mantica, P., Meo, F., Milani, F., Monakhov, I., Murari, A., Nguyen, F., Noterdaeme, J.-M., Ongena, J., Petrov, Y., Rachlew, E., Riccardo, V., Righi, E., Rimini, F., Stamp, M., Tuccillo, A.A., Zastrow, D.-D., Zerbini, M., Mantsinen, M.J., Mayoral, M.-L., Eester, D. Van, Alper, B., Barnsley, R., Beaumont, P., Bucalossi, J., Coffey, I., Conroy, S., Baar, M. de, Vries, P. de, Erents, K., Figueiredo, A., Bondhalekar, A., Gowers, C., Hellsten, T., Joffrin, E., Kiptily, V., Lamalle, P.U., Lawson, K., Lyssoivan, A., Mailloux, J., Mantica, P., Meo, F., Milani, F., Monakhov, I., Murari, A., Nguyen, F., Noterdaeme, J.-M., Ongena, J., Petrov, Y., Rachlew, E., Riccardo, V., Righi, E., Rimini, F., Stamp, M., Tuccillo, A.A., Zastrow, D.-D., and Zerbini, M.

Abstract

Ion cyclotron resonance frequencies (ICRF) mode conversion has been developed for localized on-axis and off-axis bulk electron heating on the JET tokamak. The fast magnetosonic waves launched from the low-field side ICRF antennas are mode-converted to short-wavelength waves on the high-field side of the He-3 ion cyclotron resonance layer in D and He-4 plasmas and subsequently damped on the bulk electrons. The resulting electron power deposition, measured using ICRF power modulation, is narrow with a typical full-width at half-maximum of approximate to30 cm (i.e. about 30% of the minor radius) and the total deposited power to electrons comprises at least up to 80% of the applied ICRF power. The ICRF mode conversion power deposition has been kept constant using He-3 bleed throughout the ICRF phase with a typical duration of 4-6 s, i.e. 15-40 energy confinement times. Using waves propagating in the counter-current direction minimizes competing ion damping in the presence of co-injected deuterium beam ions.

Published
2004

44. Comparison of monochromatic and polychromatic ICRH on JET

Author

Mantsinen, M. J., Laxåback, M., Salmi, A., Kiptily, V., Testa, D., Baranov, Yu., Barnsley, R., Beaumont, P., Conroy, Sean, de Vries, P., Giroud, C., Gowers, C., Hellsten, T., Ingesson, L. C., Johnson, T., Leggate, H., Mayoral, M.-L., Monak, Mantsinen, M. J., Laxåback, M., Salmi, A., Kiptily, V., Testa, D., Baranov, Yu., Barnsley, R., Beaumont, P., Conroy, Sean, de Vries, P., Giroud, C., Gowers, C., Hellsten, T., Ingesson, L. C., Johnson, T., Leggate, H., Mayoral, M.-L., and Monak

Published
2003

45. Recent progress on JET towards the ITER reference mode of operation at high density

Author

Ongena, J., Suttrop, W., Becoulet, M., Cordey, G., Dumortier, P., Eich, T., Ingesson, L. C., Jachmich, S., Lang, P., Loarte, A., Lomas, P., Maddison, G. P., Messiaen, A., Nave, M. F. F., Rapp, J., Saibene, G., Sartori, R., Sauter, O., Strachan, J. D., Unterberg, B., Valovic, M., Alper, B., Andrew, P., Baranov, Y., Brzozowski, Jerzy H., Bucalossi, J., Brix, M., Budny, R., Charlet, M., Coffey, I., De Baar, M., De Vries, P., Gowers, C., Hawkes, N., von Hellermann, M., Hillis, D. L., Hogan, J., Jackson, G. L., Joffrin, E., Jupen, C., Kallenbach, A., Koslowski, H. R., Lawson, K. D., Mantsinen, M., Matthews, G., Monier-Garbet, P., McDonald, D., Milani, F., Murakami, M., Murari, A., Neu, R., Parail, V., Podda, S., Puiatti, M. E., Righi, E., Sartori, F., Sarazin, Y., Staebler, A., Stamp, M., Telesca, G., Valisa, M., Weyssow, B., Zastrow, K. D., Efda-Jet workprogramme contributor, Ongena, J., Suttrop, W., Becoulet, M., Cordey, G., Dumortier, P., Eich, T., Ingesson, L. C., Jachmich, S., Lang, P., Loarte, A., Lomas, P., Maddison, G. P., Messiaen, A., Nave, M. F. F., Rapp, J., Saibene, G., Sartori, R., Sauter, O., Strachan, J. D., Unterberg, B., Valovic, M., Alper, B., Andrew, P., Baranov, Y., Brzozowski, Jerzy H., Bucalossi, J., Brix, M., Budny, R., Charlet, M., Coffey, I., De Baar, M., De Vries, P., Gowers, C., Hawkes, N., von Hellermann, M., Hillis, D. L., Hogan, J., Jackson, G. L., Joffrin, E., Jupen, C., Kallenbach, A., Koslowski, H. R., Lawson, K. D., Mantsinen, M., Matthews, G., Monier-Garbet, P., McDonald, D., Milani, F., Murakami, M., Murari, A., Neu, R., Parail, V., Podda, S., Puiatti, M. E., Righi, E., Sartori, F., Sarazin, Y., Staebler, A., Stamp, M., Telesca, G., Valisa, M., Weyssow, B., Zastrow, K. D., and Efda-Jet workprogramme contributor

Abstract

Recent progress towards obtaining high density and high confinement in JET as required for the ITER reference scenario at Q = 10 is summarized. Plasmas with simultaneous confinement H-98(y.2) = 1 and densities up to n/n(Gw) similar to 1 are now routinely obtained. This has been possible (i) by using plasmas at high (delta similar to 0.5) and medium (delta similar to 0.3-0.4) triangularity with sufficient heating power to maintain Type I ELMs, (ii) with impurity seeded plasmas at high (delta similar to 0.5) and low (delta less than or equal to 0.2) triangularity, (iii) with an optimized pellet injection sequence, maintaining the energy confinement and raising the density, and (iv) by carefully tuning the gas puff rate leading to plasmas with peaked density profiles and good confinement at long time scales. These high performance discharges exhibit Type I ELMs, with a new and more favourable behaviour observed at high densities, requiring further studies. Techniques for a possible mitigation of these ELMs are discussed, and first promising results are obtained with impurity seeding in discharges at high triangularity. Scaling studies using the new data of this year show a strong dependence of confinement on upper triangularity, density and proximity to the Greenwald limit. Observed MHD instabilities and methods to avoid these in high density and high confinement plasmas are discussed., QC 20100525

Published
2001
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46. Fusion Energy-Production from a Deuterium-Tritium Plasma in the Jet Tokamak

Author

Rebut, Ph, Gibson, A., Huguet, M., Adams, Jm, Alper, B., Altmann, H., Andersen, A., Andrew, P., Angelone, M., Aliarshad, S., Baigger, P., Bailey, W., Balet, B., Barabaschi, P., Barker, P., Barnsley, R., Baronian, M., Bartlett, Dv, Baylor, L., Bell, Ac, Benali, G., Bertoldi, P., Bertolini, E., Bhatnagar, V., Bickley, Aj, Binder, D., Bindslev, H., Bonicelli, T., Booth, Sj, Bosia, G., Botman, M., Boucher, D., Boucquey, P., Breger, P., Brelen, H., Brinkschulte, H., Brooks, D., Brown, A., Brown, T., Brusati, M., Bryan, S., Brzozowski, J., Buchse, R., Budd, T., Bures, M., Businaro, T., Butcher, P., Buttgereit, H., Caldwellnichols, C., Campbell, Dj, Card, P., Celentano, G., Challis, Cd, Chankin, Av, Cherubini, A., Chiron, D., Christiansen, J., Chuilon, P., Claesen, R., Clement, S., Clipsham, E., Coad, Jp, Coffey, Ih, Colton, A., Comiskey, M., Conroy, S., Cooke, M., Cooper, D., Cooper, S., Cordey, Jg, Core, W., Corrigan, G., Corti, S., Costley, Ae, Cottrell, G., Cox, M., Cripwell, P., Dacosta, O., Davies, J., Davies, N., Deblank, H., Deesch, H., Dekock, L., Deksnis, E., Delvart, F., Dennehinnov, Gb, Deschamps, G., Dickson, Wj, Dietz, Kj, Dmitrenko, Sl, Dmitrieva, M., Dobbing, J., Doglio, A., Dolgetta, N., Dorling, Se, Doyle, Pg, Duchs, Df, Duquenoy, H., Edwards, A., Ehrenberg, J., Ekedahl, A., Elevant, T., Erents, Sk, Eriksson, Lg, Fajemirokun, H., Falter, H., Freiling, J., Freville, F., Froger, C., Froissard, P., Fullard, K., Gadeberg, M., Galetsas, A., Gallagher, T., Gambier, D., Garribba, M., Gaze, P., Giannella, R., Gill, Rd, Girard, A., Gondhalekar, A., Goodall, D., Gormezano, C., Gottardi, Na, Gowers, C., Green, Bj, Grievson, B., Haange, R., Haigh, A., Hancock, Cj, Harbour, Pj, Hartrampf, T., Hawkes, Nc, Haynes, P., Hemmerich, Jl, Hender, T., Hoekzema, J., Holland, D., Hone, M., Horton, L., How, J., Huart, M., Hughes, I., Hughes, Tp, Hugon, M., Huo, Y., Ida, K., Ingram, B., Irving, M., Jacquinot, J., Jaeckel, H., Jaeger, Jf, Janeschitz, G., Jankovicz, Z., Jarvis, On, Jensen, F., Jones, Em, Jones, Hd, Jones, Lpdf, Jones, S., Jones, Ttc, Junger, Jf, Junique, F., Kaye, A., Keen, Be, Keilhacker, M., Kelly, Gj, Kerner, W., Khudoleev, A., Konig, R., Konstantellos, A., Kovanen, M., Kramer, G., Kupschus, P., Lasser, R., Last, Jr, Laundy, B., Laurotaroni, L., Laveyry, M., Lawson, K., Lennholm, M., Lingertat, J., Litunovski, Rn, Alberto Loarte, Lobel, R., Lomas, P., Loughlin, M., Lowry, C., Lupo, J., Maas, Ac, Machuzak, J., Macklin, B., Maddison, G., Maggi, Cf, Magyar, G., Mandl, W., Marchese, V., Marcon, G., Marcus, F., Mart, J., Martin, D., Martin, E., Martinsolis, R., Massmann, P., Matthews, G., Mcbryan, H., Mccracken, G., Mckivitt, J., Meriguet, P., Miele, P., Miller, A., Mills, J., Mills, Sf, Millward, P., Milverton, P., Minardi, E., Mohanti, R., Mondino, Pl, Montgomery, D., Montvai, A., Morgan, P., Morsi, H., Muir, D., Murphy, G., Myrnas, R., Nave, F., Newbert, G., Newman, M., Nielsen, P., Noll, P., Obert, W., Obrien, D., Orchard, J., Orourke, J., Ostrom, R., Ottaviani, M., Pain, M., Paoletti, F., Papastergiou, S., Parsons, W., Pasini, D., Patel, D., Peacock, A., Peacock, N., Pearce, Rjm, Pearson, D., Peng, Jf, Desilva, Rp, Perinic, G., Perry, C., Petrov, M., Pick, Ma, Plancoulaine, J., Poffe, Jp, Pohlchen, R., Porcelli, F., Porte, L., Prentice, R., Puppin, S., Putvinskii, S., Radford, G., Raimondi, T., Deandrade, Mcr, Reichle, R., Reid, J., Richards, S., Righi, E., Rimini, F., Robinson, D., Rolfe, A., Ross, Rt, Rossi, L., Russ, R., Rutter, P., Sack, Hc, Sadler, G., Saibene, G., Salanave, Jl, Sanazzaro, G., Santagiustina, A., Sartori, R., Sborchia, C., Schild, P., Schmid, M., Schmidt, G., Schunke, B., Scott, Sm, Serio, L., Sibley, A., Simonini, R., Sips, Acc, Smeulders, P., Smith, R., Stagg, R., Stamp, M., Stangeby, P., Stankiewicz, R., Start, Df, Steed, Ca, Stork, D., Stott, Pe, Stubberfield, P., Summers, D., Summers, H., Svensson, L., Tagle, Ja, Talbot, M., Tanga, A., Taroni, A., Terella, C., Terrington, A., Tesini, A., Thomas, Pr, Thompson, E., Thomsen, K., Tibone, F., Tiscornia, A., Trevalion, P., Tubbing, B., Vanbelle, P., Vanderbeken, H., Vlases, G., Vonhellermann, M., Wade, T., Walker, C., Walton, R., Ward, D., Watkins, Ml, Watkins, N., Watson, Mj, Weber, S., Wesson, J., Wijnands, Tj, Wilks, J., Wilson, D., Winkel, T., Wolf, R., Wong, D., Woodward, C., Wu, Y., Wykes, M., Young, D., Young, Id, Zannelli, L., Zolfaghari, A., and Zwingmann, W.

Abstract

The paper describes a series of experiments in the Joint European Torus (JET), culminating in the first tokamak discharges in deuterium-tritium fuelled mixtures. The experiments were undertaken within limits imposed by restrictions on vessel activation and tritium usage. The objectives were: (i) to produce more than one megawatt of fusion power in a controlled way; (ii) to validate transport codes and provide a basis for accurately predicting the performance of deuterium-tritium plasma from measurements made in deuterium plasmas; (iii) to determine tritium retention in the torus systems and to establish the effectiveness of discharge cleaning techniques for tritium removal; (iv) to demonstrate the technology related to tritium usage; and (v) to establish safe procedures for handling tritium in compliance with the regulatory requirements. A single-null X-point magnetic configuration, diverted onto the upper carbon target, with reversed toroidal magnetic field was chosen. Deuterium plasmas were heated by high power, long duration deuterium neutral beams from fourteen sources and fuelled also by up to two neutral beam sources injecting tritium. The results from three of these high performance hot ion H-mode discharges are described: a high performance pure deuterium discharge; a deuterium-tritium discharge with a 1% mixture of tritium fed to one neutral beam source; and a deuterium-tritium discharge with 100% tritium fed to two neutral beam sources. The TRANSP code was used to check the internal consistency of the measured data and to determine the origin of the measured neutron fluxes. In the best deuterium-tritium discharge, the tritium concentration was about 11% at the time of peak performance, when the total neutron emission rate was 6.0 x 10(17) neutrons/s. The integrated total neutron yield over the high power phase, which lasted about 2 s, was 7.2 x 10(17) neutrons, with an accuracy of +/- 7%. The actual fusion amplification factor, Q(DT), was about 0.15. With an optimum tritium concentration, this pulse would have produced a fusion power of almost-equal-to 5 MW and a nominal Q(DT) almost-equal-to 0.46. The same extrapolation for the pure deuterium discharge would have given almost-equal-to 11 MW and a nominal Q(DT) = 1.14, so that the total fusion power (neutrons and alpha-particles) would have exceeded the total losses in the equivalent deuterium-tritium discharge in these transient conditions. Techniques for introducing, tracking, monitoring and recovering tritium were demonstrated to be highly effective: essentially all of the tritium introduced into the neutral beam system and, so far, about two thirds of that introduced into the torus have been recovered.

Published
1992

47. Proton–triton nuclear reaction in ICRF heated plasmas in JET

Author

Santala, M I K, primary, Mantsinen, M J, additional, Bertalot, L, additional, Conroy, S, additional, Kiptily, V, additional, Popovichev, S, additional, Salmi, A, additional, Testa, D, additional, Baranov, Yu, additional, Beaumont, P, additional, Belo, P, additional, Brzozowski, J, additional, Cecconello, M, additional, deBaar, M, additional, deVries, P, additional, Gowers, C, additional, Noterdaeme, J-M, additional, Schlatter, C, additional, Sharapov, S, additional, and contributors, JET-EFDA, additional

Published
2006
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48. Hydrogen plasmas with ICRF inverted minority and mode conversion heating regimes in the JET tokamak

Author

Mayoral, M.-L, primary, Lamalle, P.U, additional, Eester, D. Van, additional, Lerche, E.A, additional, Beaumont, P, additional, Luna, E. De La, additional, Vries, P. De, additional, Gowers, C, additional, Felton, R, additional, Harling, J, additional, Kiptily, V, additional, Lawson, K, additional, Laxåback, M, additional, Lomas, P, additional, Mantsinen, M.J, additional, Meo, F, additional, Noterdaeme, J.-M, additional, Nunes, I, additional, Piazza, G, additional, Santala, M, additional, and contributors, JET EFDA, additional

Published
2006
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50. Expanding the operating space of ICRF on JET with a view to ITER

Author

Lamalle, P.U, primary, Mantsinen, M.J, additional, Noterdaeme, J.-M, additional, Alper, B, additional, Beaumont, P, additional, Bertalot, L, additional, Blackman, T, additional, Bobkov, Vl.V, additional, Bonheure, G, additional, Brzozowski, J, additional, Castaldo, C, additional, Conroy, S, additional, Baar, M. de, additional, Luna, E. de la, additional, Vries, P. de, additional, Durodié, F, additional, Ericsson, G, additional, Eriksson, L.-G, additional, Gowers, C, additional, Felton, R, additional, Heikkinen, J, additional, Hellsten, T, additional, Kiptily, V, additional, Lawson, K, additional, Laxåback, M, additional, Lerche, E, additional, Lomas, P, additional, Lyssoivan, A, additional, Mayoral, M.-L, additional, Meo, F, additional, Mironov, M, additional, Monakhov, I, additional, Nunes, I, additional, Piazza, G, additional, Popovichev, S, additional, Salmi, A, additional, Santala, M.I.K, additional, Sharapov, S, additional, Tala, T, additional, Tardocchi, M, additional, Eester, D. Van, additional, Weyssow, B, additional, and contributors, JET EFDA, additional

Published
2006
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