Multi-quasiparticle isomers inLu174

Abstract

Four-, six-, and eight-quasiparticle isomers with ${K}^{\ensuremath{\pi}}={14}^{\ensuremath{-}}$, (${21}^{+}$) and (${26}^{\ensuremath{-}}$) have been identified in the deformed nucleus $^{174}\mathrm{Lu}$, in addition to the previously reported ${K}^{\ensuremath{\pi}}={13}^{{}^{+}}$, four-quasiparticle isomeric state. Analysis of alignments and in-band crossover-to-cascade branching ratios lead to the characterization of the configurations associated with the ${K}^{\ensuremath{\pi}}={14}^{\ensuremath{-}}$ and (${21}^{+}$) isomers. The excitation energies of the observed states are compared with results from multi-quasiparticle calculations that include effects of blocking and residual nucleon-nucleon interactions. Good agreement is found for medium-spin ($I=13\text{\ensuremath{-}}14\ensuremath{\hbar}$) and the highest spin ($Ig20\ensuremath{\hbar}$) states observed, but there remain ambiguities in assigning configurations in the $I=15\text{\ensuremath{-}}19\ensuremath{\hbar}$ region.