R. Pampin M.J. Loughlin M.J. Walsh
Systematic analysis of the radiation fields throughout the ITER core LIDAR diagnostic system were performed to support the design optimisation and assessment process, aiming at achieving the required performance in terms of reliability, occupational safety and interface with neighboring systems. Neutron, photon, nuclear heat and material activation…
PublishedR. 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. M. De Bock N. J. Conway M. J. Walsh P. G. Carolan N. C. Hawkes
A multichord motional Stark effect MSE system has recently been built on the MAST tokamak. In MAST the π and σ lines of the MSE spectrum overlap due to the low magnetic field typical for present day spherical tokamaks. Also, the field curvature results in a large change in the pitch angle over the observation volume. The measured polarization ang…
PublishedV. Shevchenko G. Cunningham A. Gurchenko E. Gusakov B. Lloyd M. O’Brien A. Saveliev A. Surkov F.Volpe M. Walsh
There is a comprehensive, closely-interlinked electron Bernstein wave (EBW) programme on MAST covering heating experiments, plasma start-up studies, plasma emission measurements, theory and modelling. In this paper we report on proof-of-principle EBW heating experiments conducted on MAST with a 60 GHz, 1 MW gyrotron complex. A 28 GHz (200 kW) EBW s…
PublishedV. Shevchenko G. Cunningham A. Gurchenko E. Gusakov B. Lloyd M. O’Brien A. Saveliev A. Surkov F. Volpe M. Walsh
Burning plasma spherical tokamaks (STs) rely on off-axis current drive (CD) and nonsolenoid start-up techniques. Electron Bernstein waves (EBWs) may provide efficient off-axis heating and CD in high-density ST plasmas. EBWs may also be used in the plasma start-up phase because EBW absorption and CD efficiency remain high even in relatively cold pla…
PublishedN. J. Conway P. G. Carolan J. Mccone M. J. Walsh M. Wisse
A major upgrade to the charge exchange recombination spectroscopy system on MAST has recently been implemented. The new system consists of a high-throughput spectrometer coupled to a total of 224 spatial channels, including toroidal and poloidal views of both neutral heating beams on MAST. Radial resolution is 1 cm, comparable to the ion Larmor rad…
PublishedM. Kuldkepp M. J. Walsh P. G. Carolan N. J. Conway N. C. Hawkes Et Al
Exploiting the motional Stark effect MSE in the low magnetic fields of spherical tokamaks such as MAST is complicated by the Doppler smearing of the relatively closely spaced Stark components. Extensive modeling of MSE spectra and the subsequent polarized fraction 20% of spectrally filtered light and signal to noice ratios have been performed takin…
Published