Discovery of a long-lived low-lying isomeric state inGa80

Abstract

Collinear laser spectroscopy was performed on the $^{80}\mathrm{Ga}$ isotope at ISOLDE, CERN. A low-lying isomeric state with a half-life much greater than $200$ ms was discovered. The nuclear spins and moments of the ground and isomeric states and the isomer shift are discussed. Probable spins and parities are assigned to both long-lived states (${3}^{\ensuremath{-}}$ and ${6}^{\ensuremath{-}}$) deduced from a comparison of the measured moments to shell-model calculations.