K.D. Lawson I.H. Coffey K.M. Aggarwal F.P. Keenan JET-EFDA Contributors
The main populating and depopulating mechanisms of the excited energy levels of ions in plasmas with densities
PublishedK. D. Lawson K. M. Aggarwal I. H. Coffey F. P. Keenan R. H. G. Reid et al.
The VUV/XUV spectral region is particularly rich in lines emitted by plasmas with temperatures = 30 keV used in fusion research. Examples are presented of analyses of JET tokamak data involving C VUV/XUV radiation. In the first, the C IV divertor emission is modelled, with agreement between theory and experiment to within the measurement accuracy o…
PublishedM. Goniche J. Mailloux Y. Baranov T. M. Biewer I. Coffey et al.
During high power commissioning of the JET LH launcher, the radiation and impurity release has been analyzed from various diagnostics: VUV and visible spectroscopy, bolometry. These two last diagnostics have lines-of-sight viewing the launcher and can provide information about the electron and/or impurity source localisation. Using a database of 80…
PublishedA.D. Whiteford N.R. Badnell R. Barnsley I.H. Coffey M.G. O’Mullane H.P. Summers K.-D. Zastrow
This paper focuses on the diagnostic analysis in magnetically confined fusion plasmas with attention drawn both to the methodology in common with that in astrophysics and to points of departure – such as species, transport, high density and the role of neutral hydrogen. Comment is also made on the state of high quality theoretical collision data …
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 …
PublishedK.J.H. Phillips J.A. Rainnie L. K. Harra J. Dubau F.P. Keenan N.J. Peacock
The inclusion of collisional rates for He-like Fe and Ca ions is discussed with reference to the analysis of solar flare Fe XXV and Ca XIX line emission, particularly from the Yohkoh Bragg Crystal Spectrometer (BCS). The new data are a slight improvement on calculations presently used in the BCS analysis software in that the discrepancy in the Fe X…
PublishedR. Barnsley N. J. Peacock J. Dunn I. M. Melnick I. H. Coffey et al.
A family of Johann configuration curved crystal spectrometers has been designed to share the basic engineering features of compactness, modularity, facility of alignment and focus, and incorporation of solid-state charge coupled device detector arrays. These detectors have intrinsically low noise, useful energy resolution, two-dimensional position …
PublishedF. P. Keenan S. M. Mccann et al.
Electron-impact excitation rates for transitions in heliumlike Mg xI, calculated with the R-matrix code, are used to derive the electron-density-sensitive emission line ratio R (= f/i) and temperature sensitive ratio G [ = (f+i)/r]. A comparison of these with R and G ratios determined from x-ray…
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