The high-spin states of ${}^{141}\mathrm{Pm}$ have been investigated through the reaction ${}^{126}\mathrm{Te}$(${}^{19}\mathrm{F}$,4$n$) at a beam energy of 90 MeV. A previous level scheme has been updated with spins up to 49/2$\hslash$. Six collective bands at high spins are newly observed. Based on the systematic comparison, one band is proposed as a decoupled band; two bands with strong $\Delta I=1$ $M1$ transitions inside the bands are suggested as the oblate bands with $\gamma$ $~$$-{60}^{°}$; three other bands with large signature splitting have been proposed with the oblate-triaxial deformation with $\gamma$$~$ $-{90}^{°}$. The triaxial $n$-particle-$n$-hole particle rotor model calculations for one of the oblate bands in ${}^{141}\mathrm{Pm}$ are in good agreement with the experimental data. The other characteristics for these bands have been discussed.

• Received 17 April 2011

DOI:https://doi.org/10.1103/PhysRevC.83.064303