Coulomb Excitation of the Collective Septuplet at 2.6 MeV inBi209

Beams of 18-MeV $\alpha$ particles and 70-MeV ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ were used for $E3\mathrm{}$ Coulomb excitation of the weak-coupling $3^{-}|h_{\frac{9}{2}}〉$ septuplet $J^{\pi }={\frac{3}{2}}^{+}, \cdots , \frac{15}{2^{+}}$ at 2.6 MeV in ${}_{}{}^{209}{}_{}{}^{}\mathrm{Bi}$. A complete decay scheme was obtained and short lifetimes were determined from observed Doppler effects. We deduce several absolute transition probabilities for both excitation and decay involving the multiplet and low-lying single-particle states.