F.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 PublishedA. Baron-Wiechec E. Fortuna-Zalesna J. Grzonka M. Rubel A. Widdowson C. Ayres J.P. Coad C. Hardie K. Heinola G.F. Matthews JET Contributors
Results of the first dust survey in JET with the ITER - Like Wall (JET - ILW) are presented. The sampling was performed using adhesive stickers from the divertor tiles where the greatest material deposition was detected after the first JET - ILW campaign in 2011 - 2012. The emphasis was especially on metal particles (Be and W) with the aim to deter…
Preprint PublishedC.F. Maggi S. Saarelma F.J. Casson C. Challis E. de la Luna L. Frassinetti C. Giroud E. Joffrin J. Simpson M. Beurskens I. Chapman J. Hobirk M. Leyland P. Lomas C. Lowry I. Nunes F. Rimini A.C.C. Sips H. Urano JET Contributors
New experiments in 2013-2014 have investigated the physics responsible for the decrease in H-mode pedestal confinement observed in the initial phase of JET-ILW operation (2012 Experimental Campaigns). The effects of plasma triangularity, global beta and neutrals on pedestal confinement and stability have been investigated systematically. The stabil…
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 PublishedJ. Leddy B. Dudson M. Romanelli JET Contributors
Drift-reduced plasma fluid models are commonly used in plasma physics for analytic studies and simulations, so the validity of such models must be verified for the regions of parameter space in which tokamak plasmas exist. By deriving and comparing the linear dispersion relations for the drift-wave instability for both a drift-reduced model and a f…
Preprint PublishedJ. C. Flanagan M. Sertoli M. Bacharis G. F. Matthews P. C. de Vries A. Widdowson I. H. Coffey G. Arnoux B. Sieglin S. Brezinsek J. W. Coenen S. Marsen T. Craciunescu A. Murari D. Harting A. Cackett E. Hodille JET-EFDA Contributors
Recent studies dedicated to the characterisation of in-vessel dust in JET with the new ITER-like wall (ILW) show that dust levels are orders of magnitude lower compared with the latter stages of the carbon-wall (CW) period and are decreasing with operational time. Less than 1 g of dust was recovered in a recent inspection, compared with more than 2…
Preprint PublishedJ. C. Hillesheim E. Delabie H. Meyer C. F. Maggi L. Meneses E. Poli JET Contributors
High spatial resolution Doppler backscattering measurements in JET have enabled new insights into the development of the edge . We observe fine-scale spatial structures in the edge well with a wave number kr ? i ˜ 0.4–0.8, consistent with stationary zonal flows, the characteristics of which vary with density. The zonal flow amplitude and wavelen…
Preprint PublishedL. Giacomelli S. Conroy F. Belli G. Gorini E. Joffrin V. Kiptily E. Lerche A. Murari V.V. Plyusnin S. Popovichev C. Reux M. Riva D.B. Syme JET EFDA Contributors
The Joint European Torus (JET, Culham, UK) is the largest tokamak in the world. JET has been upgraded over the years and recently it has also become a test facility of the components designed for ITER, the next step fusion machine under construction in Cadarache (France). At JET, the neutron emission profile of Deuterium (D) or Deuterium-Tritium (D…
PublishedU. Kruezi S. Jachmich H.R. Koslowski M. Lehnen S. Brezinsek G. Matthews JET EFDA Contributors
Disruptions, the fast accidental losses of plasma current and stored energy in tokamaks, represent asignificant risk to the mechanical structure as well as the plasma facing components of reactor-scale fusion facilities like ITER. At JET, the tokamak experiment closest to ITER in terms of operating parameters and size, massive gas injection has bee…
Preprint PublishedK.D. Lawson M. Groth P. Belo S. Brezinsek G. Corrigan A. Czarnecka E. Delabie P. Drewelow D. Harting I. KsiaSek C.F. Maggi C. Marchetto A.G. Meigs S. Menmuir M.F. Stamp S. Wiesen JET-EFDA Contributors
A discrepancy in the divertor radiated powers between EDGE2D-EIRENE simulations, both with and without drifts, and JET-ILW experiments employing a set of NBI-heated L-mode discharges with step-wise density variation is investigated. Results from a VUV/visible poloidally scanning spectrometer are used together with bolometric measurements to determi…
Preprint Published