A.Baron-Wiechec A.Widdowson E.Alves C.F.Ayres N. P. Barradas S.Brezinsek J.P.Coad N.Catarino K.Heinola J.Likonen G.F.Matthews M.Mayer P. Petersson M.Rubel W. van Renterghem I. Uytdenhouwen JET-EFDA contributors
A set of Be and W tiles removed after the first ITER-like Wall campaigns (JET-ILW) from 2011-2012 has been analysed. The results indicate that the primary erosion site is in the main chamber (Be) as in previous carbon campaigns (JET-C). In particular the limiters tiles near the mid-plane are eroded probably during the limiter phases of discharges. …
Preprint PublishedK. Heinola A. Widdowson J. Likonen E. Alves A. Baron-Wiechec N. Barradas S. Brezinsek N. Catarino P. Coad S. Koivuranta G.F. Matthews M. Mayer P. Petersson JET-EFDA Contributors
Selected Ion Beam Analysis techniques applicable for detecting deuterium and heavier impurities have been used in the post-mortem analyses of tiles removed after the first JET ITER-Like Wall (JET-ILW) campaign. Over half of the retained fuel was measured in the divertor region. The highest figures for fuel retention were obtained from regions with …
Preprint PublishedJ. Beal A. Widdowson K. Heinola A. Baron-Wiechec K. J. Gibson J. P. Coad E. Alves B. Lipschultz A. Kirschner G. F. Matthews S. Brezinsek JET-EFDA Contributors
Rotating collectors are used in JET to provide time-resolved measurements of erosion and redeposition of vessel materials. The silicon collecting disks rotate behind an aperture, driven by pulsing of the toroidal magnetic field, with the deposits analysed ex-situ by Nuclear Reaction Analysis. The angular dependence of deposition is mapped to discha…
Preprint PublishedV. Parail G. Corrigan P. Da Silva Aresta Belo E. De La Luna D. Harting F. Koechl T. Koskela A. Meigs E. Militello-Asp M. Romanelli M. Tsalas JET-EFDA contributors
The influence of the ITER-like Wall (ILW) with divertor target plate made of tungsten (W), on plasma performance in JET H-mode is being investigated since 2011 (see [1] and references therein). One of the key issues in discharges with low level of D fuelling is observed accumulation of W in the plasma core, which leads to a reduction in plasma perf…
Preprint PublishedD.M. Harting S. Wiesen M. Groth S. Brezinsek G. Corrigan G. Arnoux P. Boerner S. Devaux J. Flanagan A. Järvinen S. Marsen D. Reiter JET-EFDA contributors
We present the application of an improved EDGE2D-EIRENE SOL transport model for the ELM phase utilizing kinetic correction of the sheath-heat-transmission coefficients and heat-flux-limiting factors used in fluid SOL modelling. With a statistical analysis over a range of similar Type-I ELMy H-mode discharges performed at the end of the first JET IT…
Preprint PublishedS. C. Chapman R. O. Dendy T. N. Todd N. W. Watkins F. A. Calderon J. Morris JET Contributors
A global signature of the build-up to an intrinsic edge localized mode (ELM) is found in the temporal analytic phase of signals measured in full flux azimuthal loops in the divertor region of JET. Toroidally integrating, full flux loop signals provide a global measurement proportional to the voltage induced by changes in poloidal magnetic flux; the…
PublishedA. J. Webster J. Morris T. N. Todd S. Brezinsek P. Coad J. Likonen M. Rubel JET EFDA Contributors
A unique sequence of 120 almost identical plasmas in the Joint European Torus (JET) recently provided two orders of magnitude more statistically equivalent data than ever previously available. The purpose was to study movement of eroded plasma-facing material from JET’s new Beryllium wall, but it has allowed the statistical detection of otherwise…
PublishedE. Lerche D. Van Eester Y. Kazakov P. Jacquet I. Monakhov M. Goniche L. Colas F. Rimini K. Crombé R. Dumont V. Kiptily M. Santala JET Contributors
Heating single ion species plasmas with ICRF is a challenging task: Fundamental ion cyclotron heating (w = w ci ) suffers from the adverse polarization of the RF electric fields near the majority cyclotron resonance while second harmonic heating (w = 2w ci ) typically requires pre-heating of the plasma ions to become efficient. Recently, w = 2w ci …
Preprint PublishedS. Saarelma A. Järvinen M. Beurskens C. Challis L. Frassinetti C. Giroud M. Groth M. Leyland C. Maggi J. Simpson JET Contributors
The H-mode pedestal plays an important role in determining global confinement in tokamaks. In high triangularity H-mode experiments in Joint European Torus with the ITER-like wall (JET-ILW), significantly higher pedestal temperature and global confinement have been achieved with nitrogen seeding. The experimentally observed increase in pedestal hei…
Preprint PublishedV. Riccardo G. Arnoux S. Collins P. Lomas G. Matthews N. Pace V. Thompson JET EFDA Contributors
The JET ITER-like Wall (ILW) provides the same plasma facing component configuration as ITER during its active phase: beryllium in the main chamber and tungsten in the divertor. Moving from a carbon-based wall to an all metal wall requires some operational adjustment. The reduction in radiation at the plasma edge and in the divertor can lead to hig…
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