Isotope shifts for S01−P0,1o3 Yb lines from multiconfiguration Dirac-Hartree-Fock calculations

Abstract

Relativistic multiconfiguration Dirac-Hartree-Fock calculations with configuration interaction are carried out for the $^{1}S_{0}$ and $^{3}P_{0,1}^{o}$ states in neutral ytterbium by use of the available grasp2018 package. From the resultant atomic state functions and the ris4 program, we evaluate the mass- and field-shift parameters for the $^{1}S_{0}\ensuremath{-}\phantom{\rule{0.16em}{0ex}}^{3}P_{0}^{o}$ (clock) and $^{1}S_{0}\ensuremath{-}\phantom{\rule{0.16em}{0ex}}^{3}P_{1}^{o}$ (intercombination) lines. We present improved estimates of the nuclear charge parameters ${\ensuremath{\lambda}}^{A,{A}^{\ensuremath{'}}}$ and differences in mean-square charge radii $\ensuremath{\delta}{\ensuremath{\langle}{r}^{2}\ensuremath{\rangle}}^{A,{A}^{\ensuremath{'}}}$ and examine the second-order hyperfine interaction for the $^{3}P_{0,1}^{o}$ states. Isotope shifts for the clock transition have been estimated by three largely independent means from which we predict the unknown clock-line frequencies in bosonic Yb isotopes. Knowledge of these line frequencies has implications for King-plot nonlinearity tests and the search for beyond-standard-model signatures.