Observation of proton radioactivity of the (21+) high-spin isomer in 94Ag

We have observed direct one-proton decay of the 21 isomer in the N Z nuclide 94Ag into highspin states in 93Pd by detecting protons in coincidence with - correlations and applying gates based on known 93Pd levels. Two decay branches have been identified, with proton energies of 0.79(3) and 1.01(3) MeV and branching ratios of 1.9(5)% and 2.2(4)%, respectively. The corresponding partial halflife values are 21(6) and 18(4) s. The Q value of the direct proton decay of the 21 isomer was found to be 5.78(3) MeV. The very small reduced widths of the observed proton decays might reflect dominating collective configurations in the 21 isomer, and the fine structure of the proton spectrum might indicate a strong deformation of this state.