UKAEA Papers

"Torque balance and rotational stabilization of the resistive wall mode"

• C. G. Gimblett
• R. J. Hastie

A model is developed to analyze the stabilization of the resistive wall mode (RWM) by plasma rotation. Central to the model is a cylindrical plasma that is ideal magnetohydrodynamic unstable in the absence of a wall, and possesses an internal resonance [J. M. Finn, Phys. Plasmas 2 , 198 (1995)]. This system is then a qualitative model for the actua…

"Interactive optical design and realization of an optimized charge coupled device Thomson scattering system for the spherical tokamak START"

• M. J. Walsh
• N. J. Conway
• M. Dunstan
• M. J. Forrest
• R. B. Huxford

"Optimized instrumentation for edge Te and ne measurements on COMPASS-D tokamak from HeI line intensity ratios"

• A. R. Field
• P. G. Carolan
• N. J. Conway
• M. G. O’Mullane

"Vacuum ultraviolet, extreme ultraviolet, and x-ray line intensity normalization technique applied to tokamak plasmas"

• N. J. Peacock
• K. D. Lawson
• R. Barnsley
• H. Chen

An empirical procedure, ‘‘LINT,’’ for relating emission line intensities of intrinsic impurity ions to their elemental contributions to the total, bolometric, radiation loss and the volume-averaged effective ion charge, Zeff , has been developed and applied to limiter plasmas in the JET tokamak. In this article we discuss extensions to the …

"Access to second stability region for coupled peeling-ballooning modes in tokamaks"

• H. R. Wilson
• R. L. Miller

The peeling mode restricts access to the second stability region of the ideal ballooning mode at the tokamak plasma edge. Using a two-dimensional, high toroidal mode number eigenmode code employing a model tokamak equilibrium, it is shown that a window to second stability exists for a sufficiently deep magnetic well. The different mode structures o…

"A sandpile model with dual scaling regimes for laboratory, space and astrophysical plasmas"

• S. C. Chapman
• R. O. Dendy
• G. Rowlands

There is increasing evidence that the Earth’s magnetosphere, like other macroscopic confined plasma systems (magnetic fusion plasmas, astrophysical accretion discs), displays sandpile-type phenomenology so that energy dissipation is by means of avalanches which do not have an intrinsic scale. This may in turn imply that these systems evolve via s…

"Influence of continuous spectrum on ballooning instabilities in plasmas with shear-flow"

• J. B. Taylor

"A nonlinear dynamic model of relaxation oscillations in tokamaks"

• A. Thyagaraja
• F. A. Haas
• D. J. Harvey

Tokamaks exhibit several types of relaxation oscillations such as sawteeth, fishbones and Edge Localized Modes (ELMs) under appropriate conditions. Several authors have introduced model nonlinear dynamic systems with a small number of degrees of freedom which can illustrate the generic characteristics of such oscillations. In these models, one focu…

"Magneto-hydro-dynamic limits in spherical tokamaks"

• T. C. Hender
• S. J. Allfrey
• R. Akers
• L. C. Appel
• M. K. Bevir
• et al.

"Ideal magnetohydrodynamic stability of the tokamak high-confinementmode edge region"

• H. R. Wilson
• J. W. Connor
• A. R. Field
• S. J. Fielding
• R. L. Miller
• et al.

The ideal magnetohydrodynamic (MHD) stability of the tokamak edge is analyzed, with particular emphasis on radially localized instabilities; it is proposed that these are responsible for edge pressure gradient limits and edge localized modes (ELMS). Data and stability calculations from DIII-D [to appear in Proceedings of the 16th International Conf…