P. 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 PurchaseP.A. Schneider C. Angioni L. Frassinetti L. Horvath M. Maslov F. Auriemma M. Cavedon C.D. Challis E. Delabie M.G. Dunne J.M. Fontdecaba Climent J. Hobirk A. Kappatou D.L. Keeling B. Kurzan M. Lennholm B. Lomanovski C.F. Maggi R.M. McDermott T. Pütterich A. Thorman M. Willensdorfer
Experiments in ASDEX Upgrade (AUG) and JET with the ITER-like wall (JET-ILW) are performed to separate the pedestal and core contributions to confinement in H-modes with different main ion masses. A strong isotope mass dependence in the pedestal is found which is enhanced at high gas puffing. This is because the ELM type changes when going fro…
Preprint PublishedC.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)…
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…
PreprintJ.C. Hillesheim E. Delabie E. Solano C.F. Maggi H. Meyer E. Belonohy I. Carvalho E. de la Luna A. Drenik M. Gelfusa C. Giroud J. Hobirk A.E. Hubbard A. Kappatou H.T. Kim A. Huber E. Lerche B. Lomanowski M. Mantsinen S. Menmuir I. Nunes E. Peluso F. Rimini P.A. Schneider M. Stamp G. Verdoolaege JET Contributors
Unraveling the conditions that permit access to H-mode continues to be an unresolved physics issue for tokamaks, and accurate extrapolations are important for planning ITER operations and DEMO design constraints. Experiments have been performed in JET, with the ITER-like W/Be wall, to increase the confidence of predictions for the L-H transition po…
Preprint PublishedB. Geiger A. N. Karpushov S. Sharapov R. Akers A. Bock M. Dunne B. Duval M. Fontana L. Giannone J. Hobirk C. Hopf A.S. Jacobsen D. Keeling P. Lauber C. Marini P. ZS. Poloskei M. Salewski O. Sauter P. A. Schneider D. Testa A.J. Van Vuuren M. Willensdorfer TCV Team ASDEX Upgrade Team EUROfusion MST15 Team
The fast-ion transport has been investigated in low-collisionality discharges at ASDEX Upgrade and TCV using offaxis neutral beams. In both devices Alfven eigenmode activity was observed which does, however, not strongly affect the global fast-ion confinement. In contrast, charge exchange losses have been identified to have a strong effect. At TCV …
PreprintK. K. Kirov E. Belonohy C. D. Challis J. Eriksson D. Frigione L. Garzotti L. Giacomelli J. Hobirk A. Kappatou D. Keeling D. King E. Lerche P. J. Lomas M. Nocente C. Reux F. G. Rimini A. C. C. Sips D. Van Eester JET Contributors
Achieving high neutron yields in today’s fusion research relies on high power auxiliary heating in order to attain required core temperatures. This is usually achieved by means of high Neutral Beam (NB) and Radio Frequency (RF) power. Application of NB power is accompanied by production of fast beam ions and associated Beam-Target (BT) reactio…
Preprint PublishedD. Gallart M. Mantsinen C. Challis D. Frigione J. Graves E. Belonohy F. Casson A. Czarnecka J. Eriksson J. Garcia M. Goniche C. Hellesen J. Hobirk P. Jacquet E. Joffrin N. Krawczyk D. King M. Lennholm E. Lerche E. Pawelec X. Sáez M. Sertoli G. Sips E. Solano M. Tsalas P. Vallejos Olivares M. Valisa
During the 2015-2016 JET campaigns many efforts have been devoted to the exploration of high-performance plasma scenarios envisaged for DT operation in JET. In this paper we review various key recent hybrid discharges and model the combined ICRF+NBI heating. These deuterium discharges with deuterium beams had the ICRF antenna frequency tuned to mat…
Preprint PublishedF.J. Casson C. Angioni E.A. Belli R. Bilato P. Mantica T. Odstrcil T Puetterich M. Valisa L. Garzotti C. Giroud J. Hobirk C.F. Maggi J. Mlynar M.L. Reinke JET EFDA contributors ASDEX-Upgrade team
The effects of poloidal asymmetries and heated minority species are shown to be necessary to accurately describe heavy impurity transport in present experiments in JET and ASDEX Upgrade. Plasma rotation, or any small background electrostatic field in the plasma, such as that generated by anisotropic external heating can generate strong poloidal den…
Preprint Published