R.A. Bamford B. Kellett J. Bradford T.N. Todd M.G. Benton Sr R. Stafford-Allen E.P. Alves L. Silva C. Collingwood I.A. Crawford R. Bingham
If mankind is to explore the solar system beyond the confines of our Earth and Moon the problem of radiation protection must be addressed. Galactic cosmic rays and highly variable energetic solar particles are an ever-present hazard in interplanetary space. Electric and/or magnetic fields have been suggested as deflection shields in the past, but t…
PublishedA. Turner A. Davis
CCFE perform Monte-Carlo transport simulations on large and complex tokamak models such as ITER. Such simulations are challenging since streaming and deep penetration effects are equally important. In order to make such simulations tractable, both variance reduction (VR) techniques and parallel computing are used. It has been found that the applica…
PublishedAnthony J. Webster Richard Kemp
The mark-recapture method was devised by Petersen in 1896 to estimate the number of fish migrating into the Limfjord, and independently by Lincoln in 1930 to estimate waterfowl abundance. The technique can be applied to any search for a finite number of items by two or more people or agents, allowing the number of searched-for items to be estimated…
PublishedM. Maslov M.N.A. Beurskens M. Kempenaars J. Flanagan
The LIDAR Thomson scattering concept was proposed in 1983 and then implemented for the first time on the JET tokamak in 1987. A number of modifications were performed and published in 1995, but since then no major changes were made for almost 15 years. In 2010 a refurbishment of the diagnostic was started, with as main goals to improve its performa…
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…
PublishedIT Chapman JP Graves O Sauter C Zucca O Asunta RJ Buttery S Coda T Goodman V Igochine T Johnson M Jucker RJ La Haye M Lennholm JET-EFDA Contributors
13MW of electron cyclotron current drive (ECCD) power deposited inside the q = 1 surface is likely to reduce the sawtooth period in ITER baseline scenario below the level empirically predicted to trigger neo-classical tearing modes (NTMs). However, since the ECCD control scheme is solely predicated upon changing the local magnetic shear, it is prud…
PublishedE. Surrey M. Porton T. Davenne D. Findlay A. Letchworth J. Thomason S.G. Roberts J. Marrow,
The materials engineering data base relevant to fusion irradiation is poorly populated and it has long been recognized that a fusion spectrum neutron source will be required, the facility IFMIF being the present proposal. Re-evaluation of the regulatory approach for the EU proposed DEMO device shows that the purpose of the source can be changed fro…
PublishedE. Havlícková W. Fundamenski M. Wischmeier G. Fishpool D. Coster
As part of preparations for the new Super-X divertor (SXD) on MAST, the influence of long divertor leg is modelled by SOL transport codes. The SOLPS5.0 package is used to study the effect of the expanded divertor in two dimensions and a comparison between the conventional geometry (standard short divertor) and the SXD geometry is presented. We focu…
PublishedI.T. Chapman R.J. La Haye R.J. Buttery W.W. Heidbrink G.L. Jackson C.M. Muscatello C.C. Petty R.I. Pinsker B.J. Tobias F. Turco
Sawtooth control using electron cyclotron current drive (ECCD) has been demonstrated in ITER-like plasmas with a large fast ion fraction, wide q = 1 radius and long uncontrolled sawtooth period in DIII-D. The sawtooth period is minimized when the ECCD resonance is just inside the q = 1 surface. Sawtooth destabilization using driven current inside q…
PublishedW A Cooper J P Graves O Sauter S P Hirshman I T Chapman M Gobbin L Marrelli P Martin I Predebon D Terranova
Magnetohydrodynamic equilibrium states with a three-dimensional helical core are computed to model the MAST spherical tokamak and the RFX-mod reversed field pinch. The boundary is fixed as axisymmetric. The MAST equilibrium state has the appearance of an internal kink mode and is obtained under conditions of weak reversed central shear. The RFX-mod…
Published