Abstract
Transition frequencies of Fe II ion are known to be very sensitive to variation of the fine-structure constant . The resonance absorption lines of Fe II from objects at cosmological distances are used in a search for the possible variation of in the course of cosmic time. In this paper we calculated the dependence of the transition frequencies on ( factors) for Fe II ion. We found corrections to these coefficients from valence-valence and core-valence correlations and from the Breit interaction. Both the core-valence correlation and Breit corrections to the factors appeared to be larger than had been anticipated previously. Nevertheless our calculation confirms that the Fe II absorption lines seen in quasar spectra have large factors of both signs and thus the ion Fe II alone can be used in the search for the variation at different cosmological epochs.
- Received 13 August 2007
DOI:https://doi.org/10.1103/PhysRevA.76.052507
©2007 American Physical Society