A. Murari J. Vega J. A. Alonso E. De Laluna J. Farthing et al.
The need to understand and control the dynamics of reactor grade fusion plasmas requires the analysis of increasing amounts of data, which at JET can reach easily the level of several GBytes per shot. Therefore a series of new approaches are being pursued to store the data and to retrieve the required information. They range from loss less data com…
PublishedR. J. Buttery T. C. Hender
JET has made a strong contribution to the understanding of stability issues for the tokamak. An overview of its main achievements is presented, with emphasis on the latest progress in resolving the key issues for ITER. In particular, we conclude that control or avoidance strategies for neoclassical tearing modes (NTMs) will be necessary for good pe…
PublishedR.A. Forrest
Achieving the economically viable release of energy by the fusion process has proved a major scientific and technological challenge. The nuclear reactions involved in the fusion process are well understood, but the interaction of the neutrons with the materials surrounding the plasma is an area of current research. The neutrons have energies larger…
PublishedY. Liang H. R. Koslowski P. R. Thomas E. Nardon B. Alper P. Andrew Y. Andrew G. Arnoux Y. Baranov M. Bécoulet M. Beurskens T. Biewer M. Bigi K. Crombe E. De La Luna P. De Vries W. Fundamenski S. Gerasimov C. Giroud M. P. Gryaznevich N.
Type-I edge-localized modes (ELMs) have been mitigated at the JET tokamak using a static external n 1 perturbation field generated by four error field correction coils located far from the plasma. During the application of the n 1 field the ELM frequency increased by a factor of 4 and the amplitude of the D signal decreased. The energy loss per ELM…
PublishedA. Thyagaraja F. Schwander K. G. McClements
Collective fast ion effects on flows in tokamaks are investigated analytically and numerically. A general analysis of noncollisional electrodynamic momentum transfer from fast ions to bulk plasma is presented, with polarization effects and dissipation in the bulk plasma taken into account. The analysis is illustrated using idealized simulations of …
PublishedE. Tassi R. J. Hastie F. Porcelli
The linear stability of a class of force-free equilibria in cylindrical geometry is investigated. The class consists of cylindrically symmetric force-free equilibria for which the ratio between the parallel current density and the magnetic field is a step function of the radius. It is suggested that plasmas in reversed field pinches could be roughl…
PublishedM. K. Lilley S. E. Sharapov
A discrete spectrum of compressional Alfvén eigenmodes and ion-ion hybrid eigenmodes is found to exist above the tritium ion cyclotron frequency in the deuterium-tritium D-T plasma of a spherical tokamak power plant STPP [H. R. Wilson and et al. , 19th IAEA Fusion Energy Conference IAEA, Lyon, France, (2002), No. FT/1-4]. An equilibrium magnetic w…
PublishedF. Louche P.U. Lamalle F. Durodié A. Borthwick
We present the results of a numerical investigation of the interaction between the ITER ICRF antenna plug (external matching option) and the surrounding wall blanket modules with the commercial software CST Microwave Studio (MWS). In particular we study the RF currents circulating on and between these modules with a simplified rectangular model of …
PublishedV. Shevchenko G. Cunningham A. Gurchenko E. Gusakov B. Lloyd M. O’Brien A. Saveliev A. Surkov F.Volpe M. Walsh
There is a comprehensive, closely-interlinked electron Bernstein wave (EBW) programme on MAST covering heating experiments, plasma start-up studies, plasma emission measurements, theory and modelling. In this paper we report on proof-of-principle EBW heating experiments conducted on MAST with a 60 GHz, 1 MW gyrotron complex. A 28 GHz (200 kW) EBW s…
PublishedM. Kuldkepp M. J. Walsh P. G. Carolan N. J. Conway N. C. Hawkes Et Al
Exploiting the motional Stark effect MSE in the low magnetic fields of spherical tokamaks such as MAST is complicated by the Doppler smearing of the relatively closely spaced Stark components. Extensive modeling of MSE spectra and the subsequent polarized fraction 20% of spectrally filtered light and signal to noice ratios have been performed takin…
Published