M. Fitzgerald R. Dumont D. Keeling J. Mailloux S. Sharapov M. Dreval A. Figueiredo R. Coelho J. Ferreira P. Rodrigues F. Nabais D. Borba Ž. Štancar G. Szepesi R.A. Tinguely N Fil P.G. Puglia H.J.C. Oliver V. Kiptily M. Baruzzo M. Lennholm P. Siren J. Garcia C.F. Maggi
A toroidal Alfven eigenmode (TAE) has been observed driven by alpha particles in the Joint European Torus (JET). The observation was made in dedicated deuterium-tritium experiments where radio-frequency (RF) heating was absent, in the so-called “afterglow” period when neutral beam heating was removed. Agreement with reduced and perturbative mod…
PreprintHJ. Sun SA. Silburn IS. Carvalho C Giroud G Fishpool GF. Matthews DB. King RB. Henriques DL. Keeling FG. Rimini L. Garzotti D. Frigione D. Van Eester D Kos M-L. Mayoral J. Mailloux C. Maggi A. Huber D. Douai PJ. Lomas L Morten M. Maslov K. Kirov P. Jacquet CG. Lowry M. Baruzzo C. Stuart J. Mitchell L. Horvath DC. McDonald JET Contributors
Unusually high power loads on the Beryllium limiter caused by Neutral Beam re-ionisation, and much cooler divertor target surfaces were observed during the recent JET tritium campaign. As both phenomena are driven by scrape-off layer (SOL) physics, the SOL features of 72 tritium H-mode discharges and their deuterium references have been studied. …
Preprint PublishedR.A. Tinguely N. Fil P.G. Puglia S. Dowson M. Porkolab V. Guillemot M. Podesta M. Baruzzo A. Fasoli M. Fitzgerald Y. Kazakov M.F.F. Nave M. Nocente J. Ongena S.E. Sharapov Z. Stancar JET Contributors.
The interaction of Alfvén Eigenmodes (AEs) and energetic particles will determine the success of future tokamaks. In JET, eight in-vessel antennas were installed to actively probe stable AEs with frequencies ranging 25 – 250 kHz and toroidal mode numbers |n| < 20. During the 2019-2020 deuterium campaign, almost 7500 resonances and …
PreprintD. B. King E. Viezzer I. Balboa M. Baruzzo E. Belonohy J. Buchanan I.S. Carvalho K. Cave-Ayland I. Coffey C.D. Challis E.G. Delabie L. Garzotti S. Hall J.Hillesheim L. Horvath E. Joffrin D. Keeling K. Kirov C.F. Maggi M. Maslov S. Saarelma S. Silburn E.R. Solano M. Stamp D. Valcarcel H.Weisen
A study of mixed hydrogen-deuterium H-mode plasmas has been carried out in JET-ILW to strengthen the physics basis for extrapolations to JET D-T operation and to support the development of strategies for isotope ratio control in future experiments. Variations of input power, gas fuelling and isotopic mixture were performed in H-mode plasmas of the…
Preprint PublishedSergei Gerasimov P. Abreu G Artaserse M. Baruzzo P. Buratti I.S. Carvalho I.H. Coffey E. de la Luna T.C. Hender R.B. Henriques R. Felton U. Kruezi P.J. Lomas P. McCullen M. Maslov E. Matveeva S. Moradi L. Piron F.G. Rimini W. Schippers G. Szepesi M. Tsalas L.E. Zakharov
The paper presents an analysis of disruptions occurring during JET-ILW plasma operations covering the period from the start of ILW (ITER-like wall) operation up to completion of JET operation in 2016. The total number of disruptions was 1951 including 466 with deliberately induced disruptions. The average disruption rate of unintended disruptions i…
Preprint PublishedF. G. Rimini D. Alves G. Arnoux M. Baruzzo E. Belonohy I. Carvalho R. Felton E. Joffrin P. Lomas P. McCullen A. Neto I. Nunes C. Reux A. Stephen D. Valcarcel S. Wiesen JET EFDA contributors
The JET tokamak is unique amongst present fusion devices in its capability to operate at high plasma current, providing the closest plasma parameters to ITER. The physics benefits of high current operation have to be balanced against the risks to the integrity of the machine due to high force disruptions. The installation of the ITER-Like Wall (ILW…
Preprint PublishedS.N. Gerasimov P. Abreu M. Baruzzo V. Drozdov A. Dvornova J. Havlicek T.C. Hender O. Hronova U. Kruezi X. Li T. Markovič R. Pánek G. Rubinacci M. Tsalas S. Ventre F. Villone L.E. Zakharov JET Contributors
Asymmetrical disruptions may occur during ITER operation and they may be accompanied by large sideways forces and rotation of the asymmetry. This is of particular concern because resonance of the rotating asymmetry with the natural frequencies of the vacuum vessel (and other in-vessel components) could lead to large dynamic amplification of the for…
Preprint PublishedP. C. De Vries M. Baruzzo G. M. D. Hogeweij S. Jachmich E. Joffrin P. J. Lomas G. F. Matthews A. Murari I. Nunes T. Pütterich C. Reux J. Vega JET-EFDA Contributors
In order to preserve the integrity of large tokamaks such as ITER, the number of disruptions has to be limited. JET has operated previously with a low frequency of disruptions (i.e., disruption rate) of 3.4% [P. C. de Vries et al., Nucl. Fusion 51, 053018 (2011)]. The start of operations with the new full-metal ITER-like wall at JET showed a marked…
PublishedM. Gelfusa A. Murari I. Lupelli N. Hawkes P. Gaudio M. Baruzzo M. Brix T. Craciunescu V. Drozdov A. Meigs E. Peluso M. Romanelli S. Schmuck B. Sieglin JET-EFDA Contributors
One of the main approaches to thermonuclear fusion relies on confining high temperature plasmas with properly shaped magnetic fields. The determination of the magnetic topology is, therefore, essential for controlling the experiments and for achieving the required performance. In Tokamaks, the reconstruction of the fields is typically formulated as…
PublishedYueqiang Liu M.S. Chu W.F. Guo F. Villone R. Albanese G. Ambrosino M. Baruzzo T. Bolzonella I.T. Chapman A.M. Garofalo C.G. Gimblett R.J. Hastie T.C. Hender G.L. Jackson R.J. La Haye M.J. Lanctot Y.K. In G. Machiori M. Okabayashi R. Pac
Two issues of the resistive wall mode (RWM) control code maturity are addressed: the inclusion of advanced mode damping physics beyond the ideal MHD description, and the possibility of taking into account the influence of 3D features of the conducting structures on the mode stability and control. Examples of formulations and computational results a…
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