Recoil-distance method lifetime measurements in Ta-173 - art. no. 034303

The nucleus of Ta-173 was populated using the reaction Tb-159(O-18.4n) Ta-1 73 at a beam energy of 84 MeV. Lifetime measurements in the bands built on two Nilsson configurations pih(9/2)[541]1/2(-) and pig(7/2)[404]7/2(+) were performed using the recoil-distance Doppler shift method. The measured lif etimes were used to extract the reduced transition probabilities B(E2). Mic roscopic Hartree-Fock theory with the angular momentum projection was used for calculating the reduced transition probabilities. The Q(t) values obtai ned from the measured B(E2) values show a larger collectivity for the h(9/2 ) band as compared to the g(7/2) band. Cranked Hartree-Fock Bogoliubov calc ulations were used for calculating the quasiparticle Routhians. The experim ental results in conjunction with the cranking calculations also explain th e experimental band-crossing delays associated with the i(13/2) neutron ali gnment in the Ta-173 nucleus.