Excited states of the ${}^{146}\mathrm{Tb}$ nucleus have been studied using $\gamma$-ray and electron spectroscopy in off-beam and in-beam modes following ${}^{112}\mathrm{Sn}$(${}^{40}\mathrm{Ar}$,$3n3p$) reaction with the use of the OSIRIS-II, HPGe detector array and the conversion electron spectrometer. The multipolarity of the 343 keV transition deexciting the $(7^{-})$ level in ${}^{146}\mathrm{Tb}$ shows mainly an $E2$ nature and the first excited state above the 23 s isomer is assigned as a $(5^{-},6^{-})$ state. The log $\mathit{ft}$ values have been deduced for 11 ${\beta }^{+}/$EC transitions populating excited states in ${}^{146}\mathrm{Gd}$. The systematic behavior of spins and parities of the long-lived levels at $0+x$ keV and the first excited states above them in the $N=81$ isotones ${}^{146}\mathrm{Tb}$, ${}^{148}\mathrm{Ho}$, and ${}^{150}\mathrm{Tm}$ is discussed.

• Received 19 November 2010

DOI:https://doi.org/10.1103/PhysRevC.83.027301