Seniority structure of Xe 82 136

The level structure of the $N=82$ nucleus $^{136}\mathrm{Xe}$ was studied with the inelastic neutron scattering reaction followed by $\ensuremath{\gamma}$-ray detection. A number of the spins and parities were reassigned, and many level lifetimes were determined for the first time using the Doppler-shift attenuation method. New shell-model calculations were also performed using both the full $Z=50$--82 model space, and a reduced model space including only the $1{d}_{5/2}$ and $0{g}_{7/2}$ orbitals. This new information characterizing $^{136}\mathrm{Xe}$ was used to identify the seniority structure of the low-lying levels and to assign ${(\ensuremath{\pi}0{g}_{7/2})}_{\ensuremath{\upsilon}=0}^{4}$, ${(\ensuremath{\pi}0{g}_{7/2})}_{\ensuremath{\upsilon}=2}^{4}$, ${(\ensuremath{\pi}0{g}_{7/2})}_{\ensuremath{\upsilon}=4}^{4}$, $(\ensuremath{\pi}1{d}_{5/2}){(\ensuremath{\pi}0{g}_{7/2})}_{\ensuremath{\upsilon}=1}^{3}$, and ${(\ensuremath{\pi}1{d}_{5/2})}^{2}{(\ensuremath{\pi}0{g}_{7/2})}_{\ensuremath{\upsilon}=0}^{2}$ configurations to describe all observed states below 2.8 MeV.