In deep-inelastic collisions of 8 MeV/nucleon ${}^{76}\mathrm{Ge}$ projectiles with ${}^{198}\mathrm{Pt}$, we have found a $T_{1/2}=0.25\mathrm{}\left(3\right)\mu \mathrm{s}$ isomer in ${}^{71}\mathrm{Cu}$ which decays through a $\gamma$-ray cascade of 133-495-939-1189 keV to the $\pi p_{3/2}$ ground state. The detector setup records the $\gamma$ rays of the isomeric decay as well as data on the fragment which provide its isotopic assignment. The new ${}^{71}\mathrm{Cu}$ levels are firmly assigned as the five yrast states of the $\nu g_{9/2}^2\pi p_{3/2}$ configuration; a parameter-free shell model calculation using the two-body residual interactions as observed in ${}^{70}\mathrm{Cu}$ and ${}^{70}\mathrm{Ni}$ predicts the ${}^{71}\mathrm{Cu}$ data with excellent accuracy.

• Received 29 June 1998

DOI:https://doi.org/10.1103/PhysRevLett.81.4100