arXiv:1909.10516 · Physical Review A
Combining experiments and relativistic theory for establishing accurate radiative quantities in atoms: The lifetime of the 2P3/2 state in Ca+40
Ziv Meir, Mudit Sinhal, Marianna S. Safronova, Stefan Willitsch
Abstract
We report a precise determination of the lifetime of the $(4p){\phantom{\rule{0.16em}{0ex}}}^{2}{P}_{3/2}$ state of $^{40}\mathrm{Ca}^{+}$, ${\ensuremath{\tau}}_{{P}_{3/2}}=6.639(42)\phantom{\rule{0.16em}{0ex}}\mathrm{ns}$, using a combination of measurements of the induced light shift and scattering rate on a single trapped ion. Good agreement with the result of a recent high-level theoretical calculation, 6.69(6) ns [M. S. Safronova et al., Phys. Rev. A 83, 012503 (2011)], but a 6-$\ensuremath{\sigma}$ discrepancy with the most precise previous experimental value, 6.924(19) ns [J. Jin et al., Phys. Rev. Lett. 70, 3213 (1993)], is found. To corroborate the consistency and accuracy of the new measurements, relativistically corrected ratios of reduced-dipole-matrix elements are used to directly compare our result with a recent result for the ${P}_{1/2}$ state, yielding a good agreement. The application of the present method to precise determinations of radiative quantities of molecular systems is discussed.