Beam-laser lifetime measurements of Yb ii energy levels

Laser excitation of a fast beam of ${\mathrm{Yb}}^{+}$ ions has been used to make measurements of the radiative lifetimes of eight Yb i i energy levels, four of which were excited via transitions from the ion-trap metastable level 4${\mathit{f}}^{13}$6${\mathit{s}}^2$ ${}_{}{}^2{}_{}{}^{}$ ${\mathit{F}}_{7/2}^{\mathit{o}}$. Comparison is made with the lifetimes that may be derived from the semiempirical pseudorelativistic Hartree-Fock calculation by Fawcett and Wilson [At. Data Nucl. Data Tables 48, 241 (1991)], the agreement being within 50% for seven of the eight levels considered.