Excited states in ${}_{}{}^{195}{}_{}{}^{}\mathrm{Bi}$ were populated by the ${}_{}{}^{182}{}_{}{}^{}\mathrm{W}$${(}^{19}$F,6n) and ${}_{}{}^{169}{}_{}{}^{}\mathrm{Tm}$${(}^{30}$Si,4n) reactions. The subsequent γ-ray emission was studied using in-beam spectroscopic methods including excitation functions, γ-ray angular distributions, γ-γ-t coincidence, conversion electron, and pulsed-beam-γ timing measurements. Three isomeric states were located in ${}_{}{}^{195}{}_{}{}^{}[J^{\pi }$,$t_{1/2}$,E]: ${\left[\mathrm{}\right((13/2\mathrm{})\mathrm{}}^{+}$), 32±2 ns, 888 keV]; ${\left[\mathrm{}\right((25/2\mathrm{})\mathrm{}}^{+}$), 80±10 ns, 2196 keV]; and ${\left[\mathrm{}\right((29/2\mathrm{})\mathrm{}}^{\mathrm{-}}$), 750±50 ns, 2311+Δ keV]. The structure of the observed states is interpreted within the shell-model framework. Systematic features of excited state energies and transition rates in the odd-A bismuth isotopes are discussed. A comparison of intruder states analogous to those in odd-A antimony nuclei of the Z=50 transition region is made.

• Received 19 December 1985

DOI:https://doi.org/10.1103/PhysRevC.33.1641