Rotational band properties of 173W

High-spin states in W-173 have been studied using the Nd-150(Si-28, 5n)W-173 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(M1)/B(E2) 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.