H. Tojo A. Ejiri M. P. Gryaznevich Y. Takase Y. Adachi
A method to determine the poloidal mode number m in a spherical tokamak based on magnetic probe data was developed. Perturbed magnetic fields at Mirnov coils are calculated for distributed helical filamentary currents on rational surfaces assuming the maximum current amplitude, m and n toroidal mode number, and the toroidal location of the filament…
PublishedI. G. Abel M. Barnes S. C. Cowley W. Dorland G. W. Hammett A. A. Schekochihin T. Tatsuno
We motivate the need to include collisional dissipation in gyrokinetic turbulence simulations, and constract criteria for a physically vaUd model of such dissipation. A new analytically manageable operator satisfying those criteria is presented and transformed into gyrokinetic variables. The form of conservation laws for collision operators in gyro…
PublishedJ.-M. Noterdaeme L.-G. Eriksson M. Mantsinen M.-L. Mayoral D. Van Eester J. Mailloux C. Gormezano T. T. C. Jones
The physics studies of the three “heating” systems that are installed on JET are reviewed. Results from the beginning of JET up to now are presented with some emphasis on the more recent ones. The systems were used not only for heating, where JET has laid the groundwork to qualify them for heating the next generation of machines to ignition, bu…
PublishedYueqiang Liu A. R. Albanese A. Portone G. Rubinacci F. Villone
In a fusion device such as a tokamak, it is well known that an unstable external kink mode, driven either by the plasma current or pressure, produces an external magnetic field perturbation, which induces stabilizing image currents in the surrounding conducting structures, such as the vacuum vessels made of low resistivity materials. The image curr…
PublishedS. Dormido-Canto G. Farias J. Vega R. Dormido J. Sánchez N. Duro H. Vargas A. Murari JET-EFDA Contributors
The last flux surface can be used to identify the plasma configuration of discharges. For automated recognition of JET configurations, a learning system based on support vector machines has been developed. Each configuration is described by 12 geometrical parameters. A multiclass system has been developed by means of the one-versus-the-rest approac…
PublishedMarco Ariola Gianmaria De Tommasi Didier Mazon Didier Moreau Fabio Piccolo Alfredo Pironti Filippo Sartori Luca Zabeo JET-EFDA Contributors
Advance tokamak scenarios are gaining more and more importance in operating tokamaks. These scenarios pose challenging control problems, since they require the simultaneous achievement of ambitious plasma parameters. The inherent coupling among the various variables calls for an integrated approach for the design of the controllers. This paper desc…
PublishedLeonid E. Zakharov Jerome Lewandowski Elizabeth L. Foley Fred M. Levinton Howard Y. Yuh Vladimir Drozdov D. C. Mcdonald
The theory of variances of equilibrium reconstruction is presented. It complements existing practices with information regarding what kind of plasma characteristics can be reconstructed, how accurately, and what remains beyond the abilities of diagnostic systems. The -curves, introduced by the present theory, give a quantitative assessment of quali…
PublishedD. Iraji A. Diallo A. Fasoli I. Furno S. Shibaev
Fast framing cameras constitute an important recent diagnostic development aimed at monitoring light emission from magnetically confined plasmas, and are now commonly used to study turbulence in plasmas. In the TORPEX toroidal device [A. Fasoli et al. , Phys. Plasmas 13 , 055902 (2006)], low frequency electrostatic fluctuations associated with drif…
PublishedM.G. Von Hellermann E.Delabie R.J.E. Jaspers W.Biel O.Marchuk H.P.Summers A.Whlteford C.Giroud N.C.Hawkes K.D.Zastrow
Charge exchange Recombination Spectroscopy (CXRS) plays a pivotal role in the diagnostics of hot fusion plasmas and is implemented currently in most of the operating devices. In the present report the main features of CXRS are summarized and supporting software packages encompassing "Spectral Analysis Code CXSFIT", "Charge Exchange Analysis Package…
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