Radiometric measurements in the vacuum ultraviolet spectral region for the analysis of fusion and ECR plasma
The radiation losses from 18 prominent spectral lines of carbon and oxygen in the range of 150-1200 Angstrom emitted from the tokamak ASDEX were measured absolutely using VUV-spectrometers calibrated with a radiometric standard based on electron impact induced line emission from gases. These lines represent a power loss P(VUV) = 131.5 kW which has to be compared with the bolometrically determined radiation loss P(RAD) = 150 kW and the total ohmic input power P(OH) = 440 kW. In the plasma model used at ASDEX, the density and temperature profiles were improved, especially the steep gradients at the plasma edge. The rate coefficients for electron impact ionisation and excitation were examined and, with improved excitation rate coefficients, the number of calculable line intensities was extended. A comparison of experimental line intensity ratios with model calculations was used as a test for the reliability of the plasma model in the important plasma edge region. Impurity concentrations and fluxes were determined. Finally, selected line intensity ratios emitted from an electron cyclotron resonance ion source were investigated. An attempt was made to determine the electron density as a function of the neutral gas pressure in the second stage of the ECR.
Bibliographic Reference: Report: IPP III/173 DE (1991) 126 pp.
Availability: Available from Max-Planck-Institut für Plasmaphysik, 8046 Garching bei München (DE)
Record Number: 199110649 / Last updated on: 1994-12-02
Original language: de
Available languages: de