Isotope shifts in hafnium from saturated-absorption spectroscopy

Isotope shifts of three lines of Hf I, lying in the red spectral region, have been measured by means of saturated-absorption spectroscopy in a hollow cathode. Combined with experimental data, previously given in the literature, and pseudo-relativistic Hartree-Fock estimates the field shifts (FS) of six relevant configurations are deduced: FS(5d2 6p2 ) = -84 mK, FS(6p2 6s2 ) = 36 mK, FS(5d6p2 6s) = -28 mK, FS(5d3 6p) = -90 mK, FS(5d4 ) = -94 mK and FS(5d6s2 6p) = 12 mK, referred to 5d2 6s2 . For these three studied spectral lines, connecting the configurations 5d2 6s2and 5d6s2 6p the specific mass shifts are estimated to lie between 5 and 8 times the normal shifts, using a King plot and pseudo-relativistic estimates for the Vinti integrals, respectively.