N. VIANELLO N. WALKDEN M. DUNNE B. LOMANOWSKI E. WOLFRUM C. TSUI A. STAGNI M. GRIENER B. TAL T. EICH D. REFY D. BRIDA O. FEVRIER M. AGOSTINI H. DE OLIVEIRA S. ALEIFERIS M. BERNERT J. BOEDO M. BRIX D. CARRALERO I. CARVALHO L. FRASSINETTI C. GIROUD A. HAKOLA A. HUBER . KARHUNEN J, A. KARPUSHOV B. LABIT A. MEIGS V. NAULIN T. PEREIRA C. PEREZ VON THUN H. REIMERDES C. THEILER the ASDEX Upgrade Team the TCV team the EUROfusion MST1 Team the JET Contributors
The evolution of SOL density profiles and fluctuations have been studied at different recycling levels in 3 different tokamaks, ASDEXUpgrade, TCV and JET, all operated in HMode. In all devices we clearly observe an increase of far SOL efolding length at high …
Preprint PublishedHJ. 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 PublishedJ.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 PublishedS. S. Henderson M. Bernert C. Giroud D. Brida M. Cavedon P. David R. Dux J. R. Harrison A. Huber A. Kallenbach J. Karhunen B. Lomanowski G. Matthews A. Meigs R. A. Pitts F. Reimold M. L. Reinke S. Silburn N. Vianello S. Wiesen M. Wischmeier
While current tokamak experiments are beginning to utilise real-time feedback control systems to manage the plasma exhaust, future tokamaks still require validation of theoretical models used to predict the threshold impurity concentration required to facilitate stationary divertor operation. This work exploits new spectroscopic measurements of …
Preprint PublishedJ. Simpson D. Moulton C. Giroud F. Casson M. Groth A. Chankin L. Horvath D. S. Gahle F. Kochl
EDGE2D-EIRENE simulations show that for a H-mode JET discharge (92168) the dominant atomic neutral deuterium source at the separatrix originates from the inner divertor target. Within JETTO-EIRENE neutral sources are placed at the X-point and outer midplane (OMP). For fixed electron and ion temperature, transport and neutral temperature it is obser…
PreprintJ. Simpson D. Moulton C. Giroud D. Harting G. Corrigan M. Groth JET Contributors
EDGE2D-EIRENE simulations of upstream density and radiative power scans in JET H-mode type plasmas in vertical target predict a linear relationship between the electron and ion temperatures, and power across the separatrix. This is in contradiction to the two-point model equations which states that the upstream temperature scales at the po…
Preprint PublishedJ F Parisi F I Parra C M Roach C Giroud W Dorland D R Hatch M Barnes J C Hillesheim N Aiba J R Ball P G Ivanov
Local linear gyrokinetic simulations show that electron temperature gradient (ETG) instabilities are the fastest growing modes for kyρi >~ 0.1 in the steep gradient region for a JET pedestal discharge (92174) where the electron temperature gradient is steeper than the ion temperature gradient. Here, ky is the wa…
Preprint PublishedC. Challis R. Dumont D. Frigione L. Garzotti J. Graves E Lerche J. Mailloux M. Mantsinen F. Rimini F. Casson A. Czarneka R. Felton J. Garcia C. Giroud E. Joffrin H.-T. Kim M. Lennholm P. Lomas C. Lowry L. Meneses I Nunes et al.
The JET exploitation plan foresees D-T operations in 2019-2020. With respect to the first D-T campaign in 1998, when JET was equipped with a carbon wall, the experiments will be conducted in presence of a beryllium-tungsten ITER-like wall and will benefit from an extended and improved set of diagnostics and higher available additional heating power…
Preprint PublishedC. Giroud N. Aiba F. Militello C. Challis A. Chankin B. Lomanowski D. Hatch J. Harrison D. Frigione D. Moulton S. Pamela F. Parra J. Parisi I. Putzai D. Refy S. Saarelma C. Stavrou B. Tal E. Belonohy S. Brezinsek S. Buller C. Bowman E. Delabie A. Field J. Fontdecaba A. Huber A. Meigs S. Menmuir J. Simpson JET Contributors
Preprint Published
N. C. Hawkes E. Delabie S. Menmuir C. Giroud A. Meigs N. Conway T. M. Biewer D. L. Hillis
Charge-exchange spectroscopy on JET has become particularly challenging with the introduction of the ITER-like wall. The impurity spectra are weaker and contaminated by many tungsten lines. We have therefore upgraded the instrumentation to allow the simultaneous measurement of impurity and fuel-ion charge exchange by splitting the light between two…
Preprint Published