R O Dendy B Chapman G S Yun S C Chapman K G McClements S G Thatipamula M H Kim A Zalzali
Intense suprathermal radiation, with spectral peaks at multiple harmonics of the deuteron cyclotron frequency, is detected from the outer midplane edge of KSTAR deuterium plasmas that are heated by tangential neutral beam injection (NBI) of 100keV deuterons. We identify how this deuterium ion cyclotron emission (ICE) is generated, and distinguish t…
Preprint PublishedA. R. Field P. Carvalho L. Garzotti E. Lerche C. Maggi F. Rimini C. Roach S. Saarelma M. Sertoli JET contributors
In high-performance, ITER baseline-scenario pulses (3MA/2.7T) in JET-ILW with high levels (~ 32 MW) of heating power, typically ~ 20-40% of the input power is radiated, predominantly by W impurities, which are sputtered from the divertor targets and reach the confined plasma. Sustained ELMy H-mode operation at such high heating power in JET-ILW req…
Preprint PublishedT. Farley N. R. Walkden F. Militello M. Sanna J. Young S. S. Silburn J. Harrison L. Kogan I. Lupelli S. S. Henderson A. Kirk J.W. Bradley
A new inversion technique is presented for the identification of plasma filaments in wide-angle visible camera data. Direct inversion of camera data onto a field aligned basis is a poorly conditioned problem which is overcome by breaking the analysis into a `psuedo-inversion’ step followed by a `point spread function correction’ step. Camera …
Preprint PublishedN. Vianello D. Carralero C. K. Tsui V. Naulin M. Agostini J. Boedo B. Labit C. Theiler D. Aguiam S. Allan M. Bernert S. Costea I. Cziegler H. De Oliveira J. Galdon-Quiroga G. Grenfell A. Hakola C. Ionita H. Isliker A. Karpushov J. Kovacic B. Lipschultz R. Mauriozio K. McClements F. Militello J. Olsen J. J. Rasmussen T. Ravensbergen H. Reimerdes B. Schneider R. Schrittwieser M. Spolaore K. Verhaegh J. Vicente N. Walkden W. Zhang E. Wolfrum the ASDEX Upgrade Team the TCV team the EUROfusion MST1 Team
A detailed cross-device investigation on the role of filamentary dynamics in high density regimes has been performed within the EUROfusion framework comparing ASDEX-Upgrade (AUG) and TCV tokamaks. Both devices have run density ramp experiments at different levels of plasma current, keeping toroidal field or q95 constant in order to disentangle the …
Preprint PublishedN.R.Walkden B.D.Dudson C.Ham F.Militello D.Moulton F.Riva J.T.Omotani
A firm grasp of transport processes perpendicular to the magnetic field line is required in order to understand and predict heat and particle fluxes to divertor components in tokamaks. Perpendicular transport from the hot core into the scrape-off layer (SOL) upstream impacts the SOL profile at the divertor via parallel streaming along the magnetic …
Preprint PurchaseV.H. Chen F.I. Parra J.C. Hillesheim
The Doppler Backscattering (DBS) microwave diagnostic enables the non-perturbative characterisation of density fluctuations and flows, both at the edge and the core of the plasma. The large magnetic pitch angle (up to 35 degrees, compared to 15 degrees in standard tokamaks like JET) and the time-varying magnetic equilibrium make the use of DBS in s…
Preprint PublishedR O Dendy B Chapman S C Chapman K G McClements G S Yun S G Thatipamula M H Kim
During ELM crashes in deuterium plasmas in the KSTAR tokamak, the emitted electromagnetic radiation includes features with sharp spectral structure in the frequency range up to ~900MHz. Cases where the spectral peaks below ~500MHz correspond to proton cyclotron harmonics at the outer midplane edge are explained (B Chapman et al., Nucl.…
Preprint PublishedA. R. Field L. Frassinetti C. Maggi S. Saarelma JET contributors
Empirically-based power-balance calculations of the inter-ELM separatrix loss power are presented for JET pulses with both the carbon- (JET-C) and ITER-like (JET-ILW) walls, to facilitate comparisons with results of on-going, non-linear gyro-kinetic calculations of pedestal heat transport, e.g. as reported in [1]. These might be able to explain the…
PreprintMaria Lorena Richiusa Daniel Iglesias Guy F. Matthews Michael Porton Vaughan K. Thompson Zsolt Vizvary
The next D-T campaign will push JET ITER-like Wall (IWL) to high divertor power and energy levels. During the 2016 campaign, the Strike Point (SP) sweeping permitted relevant H-mode scenarios without exceeding the temperature limits imposed by JET Operation Instructions (JOIs). In the subsequent shutdown, six outer divertor tungsten-coated 2D carbo…
Preprint PublishedL. Horvath C.F. Maggi A. Chankin S. Saarelma A.R. Field E. Belonohy A. Boboc G. Corrigan E.G. Delabie J. Flanagan L. Frassinetti C. Giroud D. Harting D. Keeling D. King M. Maslov G.F. Matthews S. Menmuir S.A. Silburn J. Simpson A.C.C Sips H. Weisen K.J. Gibson JET Contributors
The pedestal structure, ELM losses and linear MHD stability are analysed in a series of JET-ILW H and D type I ELMy H-mode plasmas. The pedestal pressure (pPED) is typically higher in D than in H at the same input power, with the difference mainly due to lower density in H than in D. At the same input power, the pedestal electron pres…
Preprint Published