The Analysis of the Ge VII spectrum. Inst. Spectrosc. Preprint no.11, 28 pp. (Troitsk, Moscow Region, Russia, 1986)

The analysis of the 3d⁸ – 3d⁷4p, 3p⁶3d⁸ – 3p⁵3d⁹ and 3d⁷4s – 3d⁷4p transitions in Ge VII is presented. Ge VII spectrum was excited in a vacuum spark with electric parameters: C = 1 ÷10 µF, L = 500 ÷ 1000 nH and U = 4 ÷ 10 kV. Spectrum in the wavelength range below 210 Å was recorded on a 3-m grazing incidence (5^o grazing angle) spectrograph having a grating with 3600 l/mm. For the wavelengths above 700 Å a 6.65-m normal incidence spectrograph with the 1200 l/mm grating was used. The wavelength uncertainties are estimated to be 0.004 Å in the short wavelength region and 0.007 Å in the long wavelength region.

           The analysis resulted in the identification of 36 spectral lines of the 3p⁶3d⁸ – 3p⁵3d⁹ transitions in the range 123 – 142 Å and 235 lines of the 3d⁷4s – 3d⁷4p transitions in the range 671 – 987 Å. The wavelengths of the 3d⁸ – 3d⁷4p transitions were remeasured and their identification was extended by 37 new lines. The 3d⁸ – 3d⁷4p transition array consists now of 256 lines in the range 159 – 201 Å. All levels of the relevant configurations were found.

           The Ge vii wavelengths presented in this Preprint were never published while the energy levels can be found in: L.I.Podobedova and A.N.Ryabtsev. Energy Levels of the First Excited Configurations of Ge VII. Opt. Spectrosc. 60, 694–697 (1986).