The spectrum of the copperlike ion Kr viii was observed with a low-inductance spark and 10.7-m normal- and grazing-incidence spectrographs. A total of 46 new lines with wavelengths ranging from 115 to 696 Å were identified: 18 of the type 3d10nl–3d10nl′, 10 of the type 3d104s–3d94s4p, and 18 of the type 3d104p–3d94p2. From these lines 37 new energy levels were determined: 14 of the type 3d10nl, 10 belonging to 3d94s4p, and 13 to 3d94p2. New values for all known levels were derived by combining the present results with measurements at longer wavelength by Gallardo et al. [ Appl. Opt. 28, 5088 ( 1989)]. The ionization energy was found to be 1014665 ± 25 cm−1 (125.802 ± 0.003 eV). New wavelength measurements were made for the 3d10–3d94p, 4f resonance lines of the nickellike ion Kr ix.
© 1991 Optical Society of America
Original Manuscript: June 19, 1990
Manuscript Accepted: August 23, 1990
Published: March 1, 1991
Joseph Reader, Nicolo Acquista, and Victor Kaufman, "Spectrum and energy levels of seven-times-ionized krypton (Kr viii) and resonance lines of eight-times-ionized krypton (Kr ix)," J. Opt. Soc. Am. B 8, 538-547 (1991)