S. Saarelma M.N.A. Beurskens D. Dickinson L. Frassinetti M.J.Leyland C.M. Roach EFDA-JET Contributors
The pedestal profile measurements in high triangularity JET plasmas show that with low fuelling the pedestal width decreases during the ELM cycle and with high fuelling it stays constant. In the low fuelling case the pedestal pressure gradient keeps increasing until the ELM crash and in the high fuelling case it initially increases then saturates d…
PublishedG. Z. Hao Y. Q. Liu A. K. Wang G. Matsunaga M. Okabayashi et al.
The kinetic effect of trapped energetic particles (EPs), arising from perpendicular neutral beam injection, on the stable low-n peeling modes in tokamak plasmas is investigated, through numerical solution of the mode’s dispersion relation derived from an energy principle. A resistive-wall peeling mode with m/n = 6/1, with m and n being the poloid…
PublishedWayne Arter
Compressible ideal magnetohydrodynamics is formulated in terms of the time evolution of potential vorticity and magnetic flux per unit mass using a compact Lie bracket notation. It is demonstrated that this simplifies analytic solution in at least one very important situation relevant to magnetic fusion experiments. Potentially important implicatio…
PublishedJean-Christophe Sublet James Eastwood Guy Morgan Arjan Koning Dimitri Rochman
EASY-II is designed as a functional replacement for the previous European Activation System, EASY-2010. It has extended nuclear data and new software, FISPACT-II, written in object-style Fortran to provide new capabilities for predictions of activation, transmutation, depletion and burnup. The new FISPACT-II code has allowed us to implement many mo…
PublishedJ. R. Harrison G. M. Fishpool A. Kirk
The distribution of particles and power to plasma-facing components is of key importance in the design of next-generation fusion devices. Power and particle decay lengths have been measured in a number of MAST L-mode and H-mode discharges in order to determine their parametric dependencies, by fitting power and particle flux profiles measured by di…
PublishedM. Turnyanskiy C. D. Challis R. J. Akers M. Cecconello D. L. Keeling A. Kirk R. Lake S. D. Pinches S. Sangaroon I. Wodniak
Previous experiments on MAST and other tokamaks have indicated that the level of fast ion redistribution can exceed that expected from classical diffusion and that this level increases with beam power. In this paper we present a quantification of this effect in MAST plasmas using a recently commissioned scanning neutron camera. The observed fast io…
PublishedJ.W. Connor R.J. Hastie A. Zocco
Many models for anomalous transport consider the turbulent E × B transport arising from electrostatic micro-instabilities. In this paper we investigate whether the perturbed magnetic field that is associated with such instabilities at small but finite values of ß can lead to significant stochastic magnetic field transport. Using the tearing parit…
PublishedL. Pangione G. Mcardle J. Storrs
The MAST (Mega Ampere Spherical Tokamak) real time plasma position controller is based on an optical linear camera placed on the mid plane of the vessel. This solution has the advantage of being a direct observation of the D emissions coming from the interaction between the boundary of the plasma and neutral gas, but, on the other hand, it restrict…
PublishedP. Helander S. L. Newton
Existing numerical tools for calculating the MHD stability of magnetically confined plasmas generally assume the existence of nested flux surfaces. These tools are therefore not immediately applicable to configurations with magnetic islands or regions with an ergodic magnetic field. However, in practice, these islands or ergodic regions are often s…
PublishedY.-C. Ghim A. A. Schekochihin A. R. Field I. G. Abel M. Barnes G. Colyer S. C. Cowley F. I. Parra D. Dunai S. Zoletnik The Mast Team
Beam emission spectroscopy (BES) measurements of ion-scale density fluctuations in the MAST tokamak are used to show that the turbulence correlation time, the drift time associated with iontemperature or density gradients, the particle (ion) streaming time along the magnetic field, and the magnetic drift time are consistently comparable, suggesting…
Published