Josef Preinhaelter Jakub Urban Pavol Pavlo
The effect of the direction of the detected beam on the intensity of ECE is studied. It is found that the combined effects of the strong dependence of the conversion efficiencey of O mode at the plasma resonance on the direction of the incident wave and the partial screening of the beam waist by the MAST vessel wall, can be responsible for the weak…
PublishedM. J. Walsh P. G. Carolan A. C. Darke M. R. Dunstan M. J. Forrest R. B. Huxford R. O’Gorman K. Pechstedt S. L. Prunty R. Scannell
Both ruby laser ( 300 points ) and NdYAG laser ( 19 points ) Thomson scattering systems are used on MAST. Fast nonlinear optical switching shunts laser beams from the four 50 Hz NdYAG lasers to obtain coaxial plasma illumination. The technique allows for future expandability to many laser systems. The ruby laser system is used in parallel. A broadb…
PublishedPatrick Blanchard Elena De La Luna Chris Gowers JET-EFDA Contributors
On the Joint European Torus ( JET ) , a key source of calibrated electron temperature T e profiles is from the measurements of the full electron cyclotron emission ( ECE ) spectrum made by a Fourier transform spectrometer ( FTS ) . It is absolutely calibrated by using a calibration source inside the vacuum vessel. High spatial and temporal resoluti…
PublishedP. G. Carolan A. Patel N. J. Conway R. J. Akers C. A. Bunting G. F. Counsell J. Dowling M. R. Dunstan A. Kirk F. Lott M. N. Price M. R. Tournianski M. J. Walsh The Mast Team
The Mega Amp Spherical Torus ( MAST ) diagnostic needs are strongly influenced by physics goals that often require diagnostic integration and cross-mapping, especially in fine-scale investigations, such as transport barriers. Conversely, the unrivalled viewing access to the edge, scrape-off layer ( SOL ) and divertor regions, provided by the MAST o…
PublishedC. Silva B. Gonçalves C. Hidalgo M. A. Pedrosa K. Erents G. Matthews R. A. Pitts
A multi-probe system has been developed to investigate the importance of electron temperature fluctuations turbulent transport in the Joint European Torus boundary plasma. The compact five-pin triple probe has been designed to reduce the phase delay of fluctuations due to the finite pin separation in the standard triple probe technique, while still…
PublishedM. Kuldkepp E. Rachlew N. C. Hawkes B. Schunke
The motional Stark effect ( MSE ) diagnostic on the International Thermonuclear Experimental Reactor will need to guide the light through a labyrinth of mirrors to provide neutron shielding. Knowledge of how the mirrors change the polarization is essential for accurate determination of the q profile. The optical properties of the plasma facing mirr…
PublishedM. R. Siegrist N. Hawkes H. Weisen
This paper presents a feasibility study for a motional Stark effect ( MSE ) [ F. M. Levinton et al. , Phys. Rev. Lett. 63 , 2060 ( 1989 )] diagnostic on the TCV tokamak. A numerical simulation code has been used to identify the optimal port arrangement and geometrical layout. It predicts the expected measurement accuracy for a range of typical plas…
PublishedR. Barnsley M. O’Mullane L. C. Ingesson A. Malaquias
The impurity line and continuum emission for International Thermonuclear Experimental Reactor ( ITER ) reference H-mode and Internal Transport Barrier ( ITB ) plasmas were modeled using the SANCO impurity transport code. Using the instrument sensitivity for a spatially resolving crystal spectrometer array with doubly-curved crystals and two-dimensi…
PublishedM. J. Nelson R. Barnsley F. Keenan H. Meyer C. A. Bunting P. G. Carolan N. J. Conway G. Cunningham I. Lehane M. R. Tournianski
A curved crystal spectrometer in Johann configuration has been implemented on MAST to obtain values for electron temperature, ion temperature and toroidal velocity. The spectrometer is used to examine medium Z impurities in the soft x-ray region by utilising a Silicon ( 111 ) crystal, bent using a 4 pin bending jig, and a CCD detector sD t =8 ms d …
PublishedW.E. Han
Refinements to consequence modelling for hypothetical accidents in Fusion Power Plants have been explored. This leads to improved accuracy and a reduction in some of the conservatism inherent in previous calculations. Assumptions made in previous analyses for the Safety and Environmental Assessment of Fusion Power (SEAFP) are examined, with particu…
Published