Ground state dipole transitions in 58Ni

Nuclear resonance fluorescence measurements on 58Ni with bremsstrahlung and Ge(Li) detectors were performed to search for bound state dipole excitations. Ten levels with ground state decay widths larger than 0.3 eV have been observed in the energy region between 6 and 10 MeV for which precise excitation energies, spins and lifetimes are reported. The measured transition probabilities are compared with theoretical estimates of E1 and M1 strength in 58Ni. Since the 58Ni(γ,γ) cross sections were determined relative to strong transitions in 208Pb, the results of a separate 208Pb(γ,γ) measurement are also presented. (orig.)