UKAEA Papers

"Use of Integral Data to Improve the European Activation File"

• R. A. Forrest
• P. Bém
• J. Kopecky
• U. Von Möllendorff
• M. Pillon
• et al.

The European Activation File is the source of nuclear data for fusion activation calculations that has been developed in Europe. In order to trust the calculations made with the data, validation is essential. A key part of this is the comparison of the EAF data with integral experiments made in fusion relevant neutron spectra on a wide range of mat…

"Generation of Noninductive Current by Electron-BernsteinWaves on the COMPASS-D Tokamak"

• V. Shevchenko
• Y. Baranov
• M. O’Brien
• A. Saveliev

Electron-Bernstein waves (EBW) were excited in the plasma by mode converted extraordinary ( X ) waves launched from the high field side of the COMPASS-D tokamak at different toroidal angles. It has been found experimentally that X -mode injection perpendicular to the magnetic field provides maximum heating efficiency. Noninductive currents of up to…

"H-Mode Operation in the START Spherical Tokamak"

• A. Sykes
• R. J. Akers
• L. C. Appel
• P. G. Carolan
• J.W. Connor
• N. J. Conway
• G. F. Counsell
• A. Dnestrovskij
• Yu.N. Dnestrovskij
• M. Gryaznevich
• P. Helander
• M. P. S. Nightingale
• C. Ribeiro
• C. M. Roach
• M. Tournianski
• M. J. Walsh
• H. R. Wilson
• The S

H -mode operation has been achieved in high current I p . 200 kA plasmas in the START spherical tokamak for both neutral-beam-injection-heated and Ohmic discharges. The transition to H mode features the development of well-defined edge pedestals in density and temperature, which signifies the formation of an edge-transport barrier, and associated e…

"The unfolding of multichord Doppler spectrometry"

• N. J. Conway
• P. G. Carolan
• M. R. Tournianski

A 20-chord Doppler spectrometer is used on the START spherical tokamak to record charge-exchange recombination (CXR) spectra. ‘‘Passive’’ radiation, mostly from near the plasma edge, is also present, and comes from electron-impact excitation of C5+ as well as C6+ CXR due to thermal neutrals. The relatively wide neutral beam, together with t…

"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

"Magneto-hydro-dynamic limits in spherical tokamaks"

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

"Possible electron Bernstein wave heating scenarios for MAST"

• R. A. Cairns
• C. N. Lashmore-Davies
• M. O’Brien

"Achievement of Record beta in the START Spherical Tokamak"

• M. Gryaznevich
• R. Akers
• P. G. Carolan
• N. J. Conway
• D. Gates
• A. R. Field
• T. C. Hender
• I. Jenkins
• R. Martin
• M. P. S. Nightingale
• C. Ribeiro
• D. C. Robinson
• A. Sykes
• M. Tournianski
• M. Valovic
• M. J. Walsh

"High-performance discharges in the Small Tight Aspect Ratio Tokamak (START)"

• D. A. Gates
• R. Akers
• L. Appel
• P. G. Carolan
• N. Conway
• et al.

The Small Tight Aspect Ratio Tokamak (START) [A. Sykes et al., Nucl. Fusion 32, 769 (1994)] spherical tokamak has recently achieved the record value of toroidal beta~30% in a tokamak-like configuration. The improvements that have made these results possible are presented along with a description of the global equilibrium parameters of the discharge…

"First results from the small tight aspect ratio tokamak multifrequency pulse radar reflectometer"

• V. F. Shevchenko
• M. J. Walsh

A multifrequency pulse radar reflectometer (PRR) has been designed, commissioned, and is operating successfully on the small tight aspect ratio tokamak (START). The data obtained with this technique allow the study of the density profile evolution during the shot, revealing aspects of the plasma behavior during such events as the internal reconnect…