ExoticN=82nucleiLu153andHf154and filling of the πh11/2subshell

Microsecond isomers in the very proton-rich N=82 nuclei ${}_{}{}^{153}{}_{}{}^{}\mathrm{Lu}$ and ${}_{}{}^{154}{}_{}{}^{}\mathrm{Hf}$ have been identified by γ-ray spectroscopy following mass analysis of ${}_{}{}^{102}{}_{}{}^{}\mathrm{Pd}$ +245 MeV ${}_{}{}^{54}{}_{}{}^{}\mathrm{Fe}$ reaction products using the Daresbury Recoil Separator. The decays of the isomers, interpreted as (π$h_{11/2}$ ${)}^n$ states, are characterized. Examination of reduced E2 transition rates between (π$h_{11/2}$ ${)}^n$ states in the N=82 isotones indicates that the half-filling of the π$h_{11/2}$ subshell occurs just below Z=71.