V.G. Kiptily M. Fitzgerald S.E. Sharapov M. Poradzinski Z. Stancar P. J. Bonofiglo R. Dumont Z. Ghani V. Goloborodko S. Menmuir1 D. Keeling M. Podestà H. Sun D.M. Taylor D. Douai J. Garcia C.F. Maggi J. Mailloux F. Rimini
The fusion-born alpha-particle heating in magnetically confined fusion machines is a high priority subject for study. The self-heating of thermonuclear fusion plasma by alpha-particles was observed in recent deuterium-tritium (D-T) experiments on the Joint European Torus (JET). This observation was possible by conducting so-called “after…
PreprintThe JET contributors* (presented by J. Mailloux)
The JET 2019–2020 scientific and technological programme exploited the results of years of concerted scientific and engineering work, including the ITER-like wall (ILW: Be wall and W divertor) installed in 2010, improved diagnostic capabilities now fully available, a major neutral beam injection upgrade providing record power in 2019–2020, and …
Preprint PublishedM. 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…
PreprintK K Kirov F. Auriemma R. Bilato C. Challis E. De la Luna J. Garcia J. Hobirk P. Jacquet A. Kappatou Y. Kazakov D. Keeling D. King V. Kiptily E. Lerche C. Maggi J. Mailloux P. Mantica M. Mantsinen M. Maslov R. Sharma Z. Stancar D. Van Eester JET-EFDA contributors
Several Ion Cyclotron Resonance Heating (ICRH) schemes in DT plasma have been considered for the ITER reactor [1]. Most of these heating schemes are minority heating at fundamental frequency. In DT plasma, both reactants can also absorb RF power as majorities at fundamental n=1 or harmonic n=2 frequency. Understanding benefits of directly heatin…
PreprintG. Giruzzi M. Fontana F.P. Orsitto E. de la Luna R. Dumont L. Figini M. Maslov S. Mazzi S. Schmuck L. Senni C. Sozzi C. Challis D. Frigione J. Garcia L. Garzotti J. Hobirk A. Kappatou D. Keeling E. Lerche C. Maggi J. Mailloux F. Rimini D. Van Eester JET contributors
Recent experiments performed in JET at high level of plasma heating, in preparation of, and during the DT campaign have shown significant discrepancies between electron temperature measurements by Thomson Scattering (TS) and Electron Cyclotron Emission (ECE). In order to perform a systematic analysis of this effect, a simple model of bipolar dis…
PreprintA R Field D Fajardo F J Casson C Angioni C D Challis J Hobirk A Kappatou Hyun-Tae Kim E Lerche A Loarte J Mailloux JET Contributors
Screening of high-Z (W) impurities from the confined plasma by the temperature gradient at the hot edge pedestal of fusion-grade H-mode plasmas has been demonstrated for the first time in the JET-ILW tokamak. Through careful optimisation of the hybrid-scenario, deuterium plasmas with sufficient heating power (≳ 32MW), high enough ion temperature …
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 PublishedP. J. Bonofiglo V. Kiptily V. Goloborodko Z. Stancar M. Podesta F. E. Cecil C. D. Challis J. Hobirk A. Kappatou E. Lerche I. Carvalho J. Garcia J. Mailloux C. F. Maggi A. G. Meigs
Capacitive plasma pickup is a well-known and difficult problem for plasma-facing edge diagnostics. Ths problem must be addressed to ensure an accurate and robust interpretation of the real signal measurements versus noise. JET’s Faraday cup fast ion loss detector array is particularly prone to this issue and can be used as a …
Preprint PurchaseC.D. Challis J. Hobirk A. Kappatou E. Lerche F. Auriemma E.Belonohy I. Coffey J. Eriksson A. Field M.Fontana J.Garcia A. Ho F. Jaulmes D. Keeling D. King K. Kirov M. Lennholm C.Maggi J.Mailloux M. Maslov S. Menmuir G. Pucella E. Rachlew F. Rimini A. Sahlberg A.Sips E. Solano C. Stuart M. Valisa
A key aim of the 2021 JET deuterium-tritium (D-T) experiments was to demonstrate steady high fusion power (10-15MW) with the ITER-like Be/W first wall. Plasmas were developed using D, repeated with T to investigate and mitigate isotope effects, and run with D-T to maximise fusion power. Compared with high current (q95~3) ‘baseline’ plasmas, …
PreprintC. Giroud S. Brezinsek R. Pitts I.S. Carvalho A. Huber E. Kaveeva D. Keeling J. Mailloux S. Aleiferis B. Chapman S. Henderson L. Garzotti E. Lerche M. MArin M. Maslov M. Brix P. Carvalho I. Coffey J. Fontdecaba L. Horvath I. Jepu J. Karhunen E. Litherland-Smith A. Meigs R.B. Morales T. Pereira D. Refy Z. Stancar M. Sertoli S. Silburn G. Szepesi A. Thorman M. Tomes I. Veselova B. Viola S. Wiesen JET contributors,
JET has investigated one the key issues for the baseline scenario in ITER, the integration of a radiative divertor for heat load control with the use of neon and nitrogen as seed impurity. A characterization of the choice of the impurity seed on plasma confinement, neutrons, pedestal MHD stability, pedestal instabilities, core transport is given…
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