High-Spin States In Zr92-96 Nuclei

The Zr92-96 nuclei were produced as fission fragments following the fusion reactions Si-28+Yb-176 and P-31+Yb-176 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 Zr93-96. 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 Sr-88 assumed to be an inert core and the valence protons and neutrons filling the pi(2p(1/2),1g(9/2)) and v(2d(5/2),3s(1/2)) orbitals.