Ruben Otin Wouter Tierens Felix Parra Shafa Aria Ernesto Lerche Philippe Jacquet Igor Monakhov Pierre Dumortie Bart Van Compernolle JET Contributors
When RF waves are applied in tokamaks with metal walls, sheath rectification effects associated with the fields induced in the scrape-off layer (SOL) may lead to enhanced plasma-wall interactions (i.e. heat-loads in the limiters, RF-induced impurity sources) which can endanger the integrity of the machine and limit the RF power. Although many co…
Preprint PublishedK 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…
PreprintA. Ho J. Citrin C. D. Challis C. Bourdelle F. J. Casson J. Hobirk A. Kappatou F. Koechl E. Lerche
This work applies the coupled JINTRAC and QuaLiKiz-neural-network (QLKNN) model on the ohmic current ramp-up phase of a JET D discharge. The chosen scenario exhibits a hollow Te profile attributed to core impurity accumulation, which is observed to worsen with the increasing fuel ion mass from D to T. A dynamic D simulation was validated, evolvi…
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 …
PreprintP. 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, …
PreprintI. Ivanova-Stanik C.D. Challis A. Chomiczewska J. Hobirk A. Huber. A Kappatou E. Lerche G. Telesca R. Zagorski
The aim of this paper is to numerically study the influences of the impurities on the high power hybrid discharges in the JET ILW configuration in the DD and DT scenarios. Numerical simulations with the COREDIV code of hybrid discharges with 32MW auxiliary heating, 2.2MA plasma current and 2.8T toroidal magnetic field in the ITER-like wall (ILW)…
PreprintM. VALOVIČ Y. BARANOV A. BOBOC J. BUCHANAN J. CITRIN E. DELABIE L. GARZOTTI C. GIROUD R. MCKEAN E. LERCHE E. DE LA LUNA V. KIPTILY F. KÖCHL M. MARIN S. MENMUIR C. VON THUN G. TVALASHVILI AND THE JET CONTRIBUTORS
Control of plasma H:D isotope mix using solely shallow pellets (in H or D) was demonstrated in recent experiments, attaining ~50%:50% ratio. The isotope mix propagates from the edge to the core on the confinement timescale. Isotope dependence of energy confinement is within error bar to scaling laws. A dataset is collected for different pellet s…
PreprintG. Pucella E. Alessi P. Buratti M. V. Falessi E. Giovannozzi F. Zonca M. Baruzzo C. D. Challis R. Dumont D. Frigione L. Garzotti J. Hobirk A. Kappatou D. L. Keeling D. King E. Lerche P. J. Lomas M. Maslov I. Nunes F. Rimini P. Siren C. Sozzi M. F. Stamp Z. Stancar D. Van Eester M. Zerbini
The experimental observation of multiple oscillations likely associated with beta-induced Alfven eigenmodes with toroidal mode number n = 1, 2 during strong tearing activity in JET plasmas is reported in this work. It is found the frequencies of these oscillations range from 5 kHz to 20 kHz, being consistent with the low-frequency beta-induc…
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