Measurements of Oscillator Strengths in Fe, Zr, Mo and Ce

Research output: ThesisDoctoral Thesis (compilation)


Atomic data are needed in many different areas of science and technology. Examples of users are the astronomical community and the lighting industry. In this work, the purpose of the projects has been to produce reliable atomic data needed to solve specific astrophysical problems. Oscillator strengths, which are needed when analysing stellar absorption spectra as well as spectra of emission line objects have been measured using the emission method. This method combines the relations of relative line intensities and radiative lifetimes to give the A-value, from which the oscillator strength can be derived. A detailed investigation on the treatment of the uncertainties in f-value measurements has also been carried out.


  • Carl Martin Sikström
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Subatomic Physics


  • cerium, molybdenum, Atomic and molecular physics, Atom- och molekylärfysik, Condensed matter:electronic structure, magnetic and optical properties, electrical, magnetic resonance, supraconductors, relaxation, spectroscopy, Kondenserade materiens egenskaper:elektronstruktur, egenskaper (elektriska, astrophysics, magnetiska och optiska), spektroskopi, oscillator strengths, supraledare, zirconium, magnetisk resonans, Fourier transform spectroscopy, branching fraction, radiative lifetimes, iron
Original languageEnglish
Awarding Institution
Supervisors/Assistant supervisor
  • [unknown], [unknown], Supervisor, External person
Award date2001 Mar 30
Print ISBNs91-7874-113-0
Publication statusPublished - 2001
Publication categoryResearch

Bibliographic note

Defence details Date: 2001-03-30 Time: 10:15 Place: Fysicum, Sal B External reviewer(s) Name: Huber, Martin Title: Prof Affiliation: [unknown] --- C M Sikström, H Lundberg, G M Wahlgren, Z S Li, C Lyngå, S Johansson and D S Leckrone, "Zr II oscillator strengths and the zirconium conflict in the HgMn star chi Lupi", Astron. Astrophys. (1999) 343, 297
Z S Li, H Lundberg, C M Sikström and S Johansson, "The FERRUM project: radiative lifetimes of intermediate-excitation states of Fe II measured in a fluorescence signal induced by laser pumping from a metastable state", Eur. Phys. J. D (1999) 6, 9
C M Sikström, M Schultz-Johanning, M Kock, Z S Li, H Nilsson, S Johansson, H Lundberg and A J J Raassen, "The FERRUM project: experimental lifetimes of highly excited Fe II 3d^6 4p levels and transition probabilities", J. Phys. B: At. Mol. Opt. Phys. (1999) 32, 5687
Z S Li, H Lundberg, G M Wahlgren and C M Sikström, "Lifetime measurements in Ce I, Ce II, and Ce III using time-resolved laser spectroscopy with application to stellar abundance determinations of cerium", Phys. Rev. A (2000) 62, 032505
H Nilsson, C M Sikström, Z S Li, H Lundberg, A J J Raassen, S Johansson, D S Leckrone and S Svanberg, "The FERRUM project: new experimental and theoretical f-values for 4p-4d transitions in Fe II applied to HST spectra of chi Lupi", Astron. Astrophys. (2000) 362, 410
C M Sikström, H Pihlemark, H Nilsson, U Litzén, S Johansson, Z S Li and H Lundberg, "Experimental Mo II oscillator strengths", J. Phys. B: At. Mol. Opt. Phys. (2001) 34, 477
H Karlsson, C M Sikström, S Johansson, Z S Li and H Lundberg, "The FERRUM project: Experimental f-values for 4p-5s transitions in Fe II", submitted to Astron. Astrophys.
C M Sikström, H Nilsson, U Litzén, A Blom and H Lundberg, "Uncertainty of oscillator strengths derived from lifetimes and branching fractions", Lund Reports on Atomic Physics LRAP-267 (2001)