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Wolfgang L. Wiese, Jeffrey R. Fuhr, John M. Bridges
Abstract
Accurate determinations of atomic oscillator strengths have been a problem for a long time, and discrepancies between various numerical results have been substantial. But in recent years considerable progress has been made, especially for weak lines. Atomic structure calculations have become sophisticated as well as efficient and are now producing the majority of atomic oscillator strength data. Measurements of emission branching fractions (or relative emission intensities) in combination with cascade-free lifetimes have become an accurate experimental approach. In view of these developments, we have in the last five years updated and enlarged our compilations of the oscillator strengths of some astrophysically important spectra. We have also measured with a refined emission method a number of weak lines of several light-element spectra and found that the agreement between the most advanced calculations and our new experiments is for the strong lines typically about 10% and for the weak lines about 25%.
Wiese, W.
, Fuhr, J.
and Bridges, J.
(2010),
Towards More Accurate Atomic Oscillator Strengths, NASA LAW Workshop Proceedings , Gatlinburg, TN, US, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=907463
(Accessed October 26, 2025)