S.N. Gerasimov T.C. Hender J. Morris V. Riccardo L.E. Zakharov JET EFDA Contributors
A key feature of disruptions during Vertical Displacement Events (VDEs), discovered in JET in 1996, is the toroidal variation in the measured plasma current Ip, i.e. the plasma current asymmetries, lasting for almost the entire current quench. The unique magnetic diagnostics at JET (full set of poloidal coils and saddle loops recorded either from t…
PublishedA.R. Field D. Dunai Y-C Ghim P. Hill B. Mcmillan C.M. Roach S. Saarelma A.A. Schekochihin S. Zoletnik The Mast Team
Observations of ion-scale density turbulence of relative amplitude are available on the Mega Amp Spherical Tokamak (MAST) using a 2D (8 radial × 4 poloidal channel) imaging Beam Emission Spectroscopy (BES) diagnostic. Spatial and temporal characteristics of this turbulence, i.e., amplitudes, correlation times, radial and perpendicular correlation …
PublishedZhirui Wang Jong-Kyu Park Yueqiang Liu Nikolas Logan Kimin Kim Jonathan E. Menard
Systematic comparison and numerical benchmarking have been successfully carried out among three different approaches of neoclassical toroidal viscosity (NTV) theory and the corresponding codes: IPEC-PENT is developed based on the combined NTV theory but without geometric simplifications [Park et al., Phys. Rev. Lett. 102, 065002 (2009)]; MARS-Q inc…
PublishedD. Dickinson C. M. Roach J. M. Skipp H. R. Wilson
Solutions to a model 2D eigenmode equation describing micro-instabilities in tokamak plasmas are presented that demonstrate a sensitivity of the mode structure and stability to plasma profiles. In narrow regions of parameter space, with special plasma profiles, a maximally unstable mode is found that balloons on the outboard side of the tokamak. Th…
PublishedS. Menmuir C. Giroud T. M. Biewer I. H. Coffey E. Delabie N. C. Hawkes M. Sertoli JET EFDA Contributors
Charge exchange spectroscopy has long been a key diagnostic tool for fusion plasmas and is well developed in devices with Carbon Plasma-Facing Components. Operation with the ITER-like wall at JET has resulted in changes to the spectrum in the region of the Carbon charge exchange line at 529.06nm and demonstrates the need to revise the core charge e…
PublishedO.M. Jones C.A. Michael K.G. McClements N.J. Conway B. Crowley R.J. Akers R.J. Lake S.D. Pinches The Mast Team
Using the recently-installed Fast-Ion Deuterium Alpha (FIDA) spectrometer, the effects of low-frequency (20 - 50 kHz) chirping energetic particle modes with toroidal mode number n = 1 on the NBI-driven fast-ion population in MAST plasmas are considered. Results from the FIDA diagnostic are presented and discussed in the light of the present theoret…
PublishedAnthony J. Webster JET EFDA Contributors
The generic question is considered: How can we determine the probability of an otherwise quasirandom event, having been triggered by an external influence? A specific problem is the quantification of the success of techniques to trigger, and hence control, plasma instabilities in magnetically confined fusion (MCF) experiments. The successful develo…
PublishedG. Arnoux I. Balboa M. Clever S. Devaux P. De Vries T. Eich M. Firdaouss S. Jachmich M. Lehnen P.J. Lomas G.F. Matthews Ph. Mertens I. Nunes V. Riccardo C. Ruset B. Sieglin D.F. Valcarcel J. Wilson K.-D. Zastrow JET-EFDA Contributors
The ITER-like wall (ILW) at JET is a unique opportunity to study the combination of material (beryllium and tungsten) that will be used for the plasma facing components (PFC) in ITER. Both the limiters (Be) and divertor (CFC W coated and bulk W) have been designed to maximise their power handling capability. During the last experimental campaign (O…
PublishedJ. W. Berkery Y. Q. Liu Z. R. Wang S. A. Sabbagh N. C. Logan J.-K. Park J. Manickam R. Betti
Validating the calculations of kinetic resistive wall mode (RWM) stability is important for confidently predicting RWM stable operating regions in ITER and other high performance tokamaks for disruption avoidance. Benchmarking the calculations of the Magnetohydrodynamic Resistive Spectrum—Kinetic (MARS-K) [Y. Liu et al., Phys. Plasmas 15, 112503 …
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