Picture of two heads

Open Access research that challenges the mind...

The Strathprints institutional repository is a digital archive of University of Strathclyde research outputs. Strathprints provides access to thousands of Open Access research papers by University of Strathclyde researchers, including those from the School of Psychological Sciences & Health - but also papers by researchers based within the Faculties of Science, Engineering, Humanities & Social Sciences, and from the Strathclyde Business School.

Discover more...

Interpretation of spatially resolved helium line ratios on mast

Lisgo, S. and Borner, P. and Counsell, G.F. and Dowling, J. and Kirk, A. and Scannell, R. and O'Mullane, M.G. and Reiter, D. (2009) Interpretation of spatially resolved helium line ratios on mast. Journal of Nuclear Materials, 390-91. pp. 1078-1080. ISSN 0022-3115

Full text not available in this repository. (Request a copy from the Strathclyde author)

Abstract

The tokamak boundary plasma is inherently 2D/3D, which impedes the detailed validation of transport models due to the limited spatial coverage of most diagnostics. A potential method for determining the 2D profiles of n(e) and T-e in the plasma volume is to resolve spatially the emission ratios of atomic helium, principally the lines at 667, 706 and 728 nm. Unfortunately, there are several challenges associated with this approach: the traditional use of line-of-sight spectrometer data; crowding by other impurity lines; low signal levels; reliance on accurate atomic physics; and He I meta-stables. Several of these issues are explored in the present study, which utilises tomographic reconstruction of filtered CCD camera images to measure He emission throughout the divertor. Plasma gradients are resolved and compared with results from the OSM-EIRENE code. The near-target n(e) and T-e values agree with Langmuir probe measurements to within a factor similar to 2.