Gamma radiation from theN=Znucleus4080Zr40

The very neutron-deficient isotope ${}_{}{}^{80}{}_{}{}^{}\mathrm{Zr}$ was produced in the reaction ${}_{}{}^{24}{}_{}{}^{}\mathrm{Mg}$ ${(}^{58}$Ni, 2n${)}^{80}$Zr at 190 MeV with a cross section of σ=10±5 μb and was identified with the Daresbury Recoil Separator. The observation reflects a fiftyfold increase in sensitivity for in-beam spectroscopy of exotic nuclei. Coincidence measurements between the isolated isotope and prompt gamma radiation allowed the identification of decays from low-lying states at E=290 and 828 keV which indicate that ${}_{}{}^{80}{}_{}{}^{}\mathrm{Zr}$ has an extremely large quadrupole deformation of ${\beta }_2$≊0.4.