173Wの回転バンド

High-spin states in $^{173}$W have been studied using the $^{150}$Nd($^{28}$Si,5$n$)$^{173}$W reaction at beam energies of 135 and 140 MeV. The previously known bands associated with the 7/2$^+$[633], 5/2$^-$[512], and 1/2$^-$[521] configurations are extended significantly, and the unfavored signature branch of the 1/2$^-$[521] band is established for the first time. The band properties, such as level spacings, band-crossing frequencies, alignment gains, and signature splittings, are discussed with an emphasis on the low-spin signature inversion observed in the 5/2$^-$[512] band. By comparing the experimental $B$($M$1)/$B$($E$2) ratios with the theoretical values, we conclude that the configuration of the 5/2$^-$[512] band is quite pure at low spins without appreciable admixture of the 5/2$^-$[523] orbit, in conflict with the particle rotor model calculated results.