Radiation distributions in TCV

Total radiative powers measured by foil bolometer and AXUV camera systems are compared to SOLPS5 simulations in low and high density deuterium and helium diverted discharges on the TCV tokamak. For low density the match between simulation and measurements is satisfactory, but at high density strongly radiating regions outside the SOLPS5 simulation grid are seen in measurements and this may indicate the presence of enhanced convective particle transport in the low field side midplane region. The chord coverage of the foil bolometer system does not, however, allow detailed resolution in this region. The comparison of foil and AXUV data also demonstrates that ageing of the AXUV diodes under plasma irradiation combined with the unevenness of the diode spectral response, strongly limits their application for total radiative power measurements. (c) 2007 Elsevier B.V. All rights reserved.