Experimental and theoretical lifetimes and transition probabilities for spectral lines in NbII

Research output: Contribution to journalArticle


Aims. We have measured and calculated lifetimes of high lying levels in Nb II, and derived absolute transition probabilities by combining the lifetimes with experimental branching fractions. Methods. The lifetimes were measured using time-resolved laser-induced fluorescence in a two-photon and two-step excitation scheme. The branching fractions were measured in intensity calibrated spectra from a hollow cathode discharge, recorded with a Fourier transform spectrometer. The calculations were performed with the relativistic Hartree-Fock method including core polarization. Results. We report experimental lifetimes of 13 levels in the 4d3(4F)5d and 4d3(4F)6s subconfigurations, at an energy around 70 000 cm-1. By combining the lifetimes with experimental branching fractions absolute transition probabilities of 59 lines are derived. The experimental results are compared with calculated values.


External organisations
  • Malmö University
  • University of Mons
  • University of Liège
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Atom and Molecular Physics and Optics


  • Atomic data, Methods: laboratory: atomic, Techniques: spectroscopic
Original languageEnglish
Article numberA102
JournalAstronomy and Astrophysics
Publication statusPublished - 2019 Jul
Publication categoryResearch