Wavelengths, energy levels and hyperfine structure constants in Ho II

Research output: Contribution to journalArticle


We recorded spectra of Ho II emitted by hollow-cathode lamps, using the ultraviolet Fourier transform spectrometer (FTS) at Lund Observatory and the 2-m FTS at the National Institute of Standards and Technology. The combined wavenumber coverage spans the interval from 8000 to 49 600 cm(-1) (12 500 to 2016 angstrom). We measured 303 lines in these spectra and used them to determine energies and hyperfine structure constants of 100 levels. Of these, 41 energy levels have not been reported previously and hyperfine structure constants have not been reported previously for 83 levels. Comparisons between the hyperfine structure constants and energy levels presented in this article and those previously determined from other studies are included and discrepancies are discussed. A theoretical study of the odd-parity levels leads to hyperfine structure parameters and to predictions for unknown excited levels of the ground-state configuration.


  • J. Gurell
  • Glenn Wahlgren
  • G. Nave
  • J-F Wyart
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Astronomy, Astrophysics and Cosmology
Original languageEnglish
JournalPhysica Scripta
Issue number3
Publication statusPublished - 2009
Publication categoryResearch