RADIATION DUE TO PSEUDO-CONTINUUM FROM HIGH-Z IMPURITIES IN UPGRADED DIVA TOKAMAK PLASMA

The many closely crowded lines (pseudo-continuum) of high-Z gold impurities are studied in detail with a calibrated grazing-incidence monochromator in hydrogen plasma, in the upgraded DIVA tokamak device with a divertor; the toroidal field is 20 kG and the peak plasma current is 40 kA. The emission spectrum of the many lines is observed in the wavelength region of 42 to 200 Å. The time-resolved spatial distribution of the emission of the many lines was measured in each element in the wavelength region. It was found that the radiation due to the many lines in the wavelength region of 120 to 200 Å concentrated in an intermediate region of the plasma column, and that the emission of the many lines in the wavelength region of 42-110 Å peaked at the plasma centre. The radiation power loss due to the many lines in the 120-200 Å region was dominant during the whole discharge. The radiation power due to the many lines corresponded to 40-70% of the total radiation power loss from the plasma volume. © 1979 IOP Publishing Ltd.