States in ${}_{}{}^{209}{}_{}{}^{}\mathrm{Bi}$ were populated with the ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}(t, 2n)$ reaction. Incident triton energies between 11 and 16 MeV were used. Gamma-ray excitation functions, angular distributions, and $\gamma -\gamma$-time coincidence spectra were measured. Approximately 50 newly-observed $\gamma$ rays have been assigned to transitions in ${}_{}{}^{209}{}_{}{}^{}\mathrm{Bi}$. Previously-unresolved doublets at $E_x=2600, 3135, \mathrm{and} 3154$ keV have been identified. A new level at 3270 keV is reported, and the 3197-keV level is verified. ${}_{}{}^{209}{}_{}{}^{}\mathrm{Bi}$ level energies are reported with an accuracy of 600 eV or less. A level scheme for $E_x<4.14\mathrm{}$ MeV is presented, including spin-parity assignments. A new $M1\mathrm{}$ transition between the ${\frac{5}{2}}^{+}$ and ${\frac{3}{2}}^{+}$ members of the $\pi h_{\frac{9}{2}}\otimes 3^{-}$ septuplet is reported. The 19 levels belonging to the $\nu g_{\frac{9}{2}}{p_{\frac{1}{2}}}^{-1\mathrm{}}$, $\pi h_{\frac{9}{2}}$ are identified.

NUCLEAR REACTIONS ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}(t, 2n\gamma ){}_{}{}^{209}{}_{}{}^{}\mathrm{Bi}$, $E_t=11-16\mathrm{}$ MeV. Measured $E_{\gamma }$, $I_{\gamma }\left(\theta \right)$, excitation functions, $\gamma \gamma t$ coinc. Deduced levels $E$, $J^{\pi }$, core-coupled multiplet structure.

• Received 29 July 1982

DOI:https://doi.org/10.1103/PhysRevC.27.1431