ENERGY-LEVELS AND THE VACUUM-ULTRAVIOLET SPECTRUM OF W-VIII

The spectrum of seven times ionized tungsten (W VIII) has been measure d in the wavelength range from 130 to 300 Angstrom with a spectral res olution of 5 Angstrom. The tungsten was injected by the blow-off metho d as an impurity in the plasma of the MT-1M tokamak. For explaining th e spectrum, an empirical method for extrapolating the unknown excitati on energy levels of complex ions based on known levels of less complex ones was developed and is presented. Copyright (C) 1996 Elsevier Scie nce Ltd.