R. Scannell M. J. Walsh P. G. Carolan A. C. Darke M. R. Dunstan R. B. Huxford G. McArdle D. Morgan G. Naylor T. O’Gorman S. Shibaev N. Barratt K. J. Gibson G. J. Tallents H. R. Wilson
A new infrared Thomson scattering system has been designed for the MAST tokamak. The system will measure at 120 spatial points with 10 mm resolution across the plasma. Eight 30 Hz 1.6 J Nd:YAG lasers will be combined to produce a sampling rate of 240 Hz. The lasers will follow separate parallel beam paths to the MAST vessel. Scattered light will b…
PublishedM. F. Thornton A. J. T. Holmes L. M. Lea G. O. R. Naylor
This paper presents the results of experimental studies on a number of different ' current carrying wire' type first grid electron suppressors: or ' inserts', as they shall be called throughout this paper. Extracted negative ion currents are compared for the different inserts over a range of field strengths. Currents are also compared to those extr…
PublishedL. M. Lea A. J. T. Holmes M. F. Thornton G. O. R. Naylor
When a suitable accelerating voltage is applied to extract negative ions from a volume production source, electrons are also extracted. If no means of suppression is utilized, the electron current in a hydrogen plasma would typically be of the order of 80-100 times the negative-ion current. In the accelerator designs in use at Culham Laboratory, el…
Published