Shape coexistence effects and superdeformation inZr84

The high-spin spectrum of ${}_{}{}^{84}{}_{}{}^{}\mathrm{Zr}$ is studied using the Strutinsky-Bogolyubov cranking model with a Woods-Saxon average potential. Calculations explain observed irregularities in the ${}_{}{}^{84}{}_{}{}^{}\mathrm{Zr}$ yrast line in terms of band crossings involving aligned $g_{9/2}$ proton and neutron bands. A transition to the superdeformed shape is predicted to occur around I∼30ħ. Experimental data are consistent with the nucleus having a well deformed (${\beta }_2$≃0.3) and triaxial (γ≃-20°) shape.