ACCURATE WAVELENGTH DETERMINATION OF THE LASING AND NONLASING LINES IN LASER-PRODUCED GERMANIUM PLASMA

The XUV spectra from laser-produced germanium plasma are investigated. The energy levels of the 2s(2)2p(5)3l and 2s2p(6)3l states with l = 0 , 1, 2 and the oscillator strengths for the transitions between these levels are calculated by the relativistic configuration-interaction (R CI) method. A high-resolution (lambda/Delta lambda similar to - 16 000 ) grazing-incidence spectrometer is used to measure the spectra in 185 -300 Angstrom. The wavelengths of the five lasing lines in Ne-like Ge and the wavelengths of the nonlasing lines have been determined with /- 0.04 Angstrom accuracy. The observed lines are assigned to the 3-3 transitions in Ne-like and Na-like Ge ions. The energies of the excite d states in Ne-like Ge ions derived from the spectroscopic measurement s are compared with the RCI and other theoretical calculations.