Rotational band structures in doubly odd 138Pm.

TLDR: High-spin states in the doubly odd nucleus {sup 138}Pm have been studied via gamma-ray spectroscopic methods following the heavy-ion fusion-evaporation reaction.

Abstract: High-spin states in the doubly odd nucleus $^{138}\mathrm{Pm}$ have been studied via gamma-ray spectroscopic methods following the $^{116}\mathrm{Cd}$${(}^{27}$Al,5n\ensuremath{\gamma}) heavy-ion fusion-evaporation reaction. Several rotational bands have been populated in the nucleus. The yrast cascade is based on two signature components of the \ensuremath{\pi}${\mathit{h}}_{11/2}$\ensuremath{\bigotimes}\ensuremath{\nu}${\mathit{h}}_{11/2}$ configuration. A sideband was observed, which is probably based on the \ensuremath{\pi}[413]5/${2}^{+}$\ensuremath{\bigotimes}\ensuremath{\nu}${\mathit{h}}_{11/2}$ configuration. Similar rotational bands built on these configurations have been observed in the neighboring doubly odd $^{134}\mathrm{Pr}$ and $^{136}\mathrm{Pm}$ nuclei. An additional \ensuremath{\Delta}I=2 band structure, not observed in these other nuclei, has also been populated. At low rotational frequencies, this band is possibly based on the \ensuremath{\pi}${\mathit{h}}_{11/2}$\ensuremath{\bigotimes}\ensuremath{\nu}[400]1/${2}^{+}$ configuration. At a frequency \ensuremath{\Elzxh}\ensuremath{\omega}\ensuremath{\sim}0.31 MeV it is crossed by a band based on the favored signature of the \ensuremath{\pi}${\mathit{h}}_{11/2}$\ensuremath{\bigotimes}\ensuremath{\nu}${\mathit{i}}_{13/2}$ configuration with an accompanying gain in alignment of \ensuremath{\sim}6\ensuremath{\Elzxh}.