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arXiv · 1710.07604

Isotope Shifts in the 7s$\rightarrow$8s Transition of Francium: Measurements and Comparison to \textit{ab initio} Theory

M. R. Kalita·J. A. Behr·A. Gorelov·M. R. Pearson·A. C. DeHart·G. Gwinner·M. J. Kossin·L. A. Orozco·S. Aubin·E. Gomez·M. S. Safronova·V. A. Dzuba·V. V. Flambaum
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Abstract

We observe the electric-dipole forbidden $7s\rightarrow8s$ transition in the francium isotopes $^{208-211}$Fr and $^{213}$Fr using a two-photon excitation scheme. We collect the atoms online from an accelerator and confine them in a magneto optical trap for the measurements. In combination with previous measurements of the $7s\rightarrow7p_{1/2}$ transition we perform a King Plot analysis. We compare the thus determined ratio of the field shift constants (1.230 $\pm$ 0.019) to results obtained from new ab initio calculations (1.234 $\pm$ 0.010) and find excellent agreement.

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M. R. Kalita, J. A. Behr, A. Gorelov, M. R. Pearson, A. C. DeHart, G. Gwinner, M. J. Kossin, L. A. Orozco, S. Aubin, E. Gomez, M. S. Safronova, V. A. Dzuba, V. V. Flambaum. 2017-10-20. Isotope Shifts in the 7s$\rightarrow$8s Transition of Francium: Measurements and Comparison to \textit{ab initio} Theory. https://doi.org/10.1103/physreva.97.042507

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