ELECTRIC DIPOLE TRANSITIONS FROM 2.6-MEV SEPTUPLET IN BI-209

The resonant scattering of electron bremsstrahlung by the 72+, 92+, and 112+ members of the 2.6-MeV septuplet in Bi209 has been studied. On the basis of the scattered intensities, and assuming ground-state branching ratios Γ0Γ of 0.5, 1.0, and 1.0, respectively, ground-state transition widths of Γ0(2.581,72+)<10 meV, Γ0(2.563,92+)=30±5 meV, and Γ0(2.598,112+)=9.0±2.4 meV were obtained. The observed transition strengths agree well with the predictions of the particle-vibration model in the form used by Hamamoto, with eeff2(E1)=0.05. © 1969 The American Physical Society.