Isotope shifts and hyperfine splitting of the ${}^1{S}_0\to {}^3{P}_1$ transition in zinc

We report laser-induced-fluorescence spectroscopy of the ${}^1{S}_0\to {}^3{P}_1$ intercombination transition in neutral zinc at $307.6\mathrm{n}\mathrm{m}$. Isotope shifts are measured for all stable isotopes with kHz-level precision, improving previous data by about two orders of magnitude. For ${}^{67}\mathrm{Z}\mathrm{n}$, we resolve the excited-state hyperfine structure and determine $\delta {\nu }_{\mathrm{C}\mathrm{O}\mathrm{G}}^{67,64}=1085.933(4)\mathrm{M}\mathrm{H}\mathrm{z}$, $A=608.922(1)\mathrm{M}\mathrm{H}\mathrm{z}$, and $B=-18.995(4)\mathrm{M}\mathrm{H}\mathrm{z}$. A King-plot comparison with the ${}^1{S}_0\to {}^1{P}_1$ transition at $214\mathrm{n}\mathrm{m}$ gives field- and mass-shift parameters of $F_{307.6,214}=1.17(5)$ and $K=-153(60)\mathrm{G}\mathrm{H}\mathrm{z}\mathrm{u}$. These results provide the spectroscopic basis for narrow-line cooling and precision measurements based on zinc, including the development of an optical clock.