The ${}^{92\text{−}96}\mathrm{Zr}$ nuclei were produced as fission fragments following the fusion reactions ${}^{28}\mathrm{Si}+{}^{176}\mathrm{Yb}$ and ${}^{31}\mathrm{P}+{}^{176}\mathrm{Yb}$ at 145 and 152 MeV bombarding energy, respectively. Prompt $\gamma$ rays emitted in the two reactions were detected with the EUROGAM II and EUROBALL IV arrays. Sequences of $\gamma$-ray transitions observed in coincidence were newly assigned to ${}^{93\text{−}96}\mathrm{Zr}$. The previously known level schemes have been extended to higher excitation energies and higher spins. The experimental results are discussed in the framework of shell-model calculations with ${}^{88}\mathrm{Sr}$ assumed to be an inert core and the valence protons and neutrons filling the $\pi (2p_{1/2},1g_{9/2})$ and $\nu (2d_{5/2},3s_{1/2})$ orbitals.

• Received 10 June 2004

DOI:https://doi.org/10.1103/PhysRevC.72.024304