Lifetimes of states in the transitional nucleus Gd152

The lifetimes of states in Gd152 have been measured by the Doppler-shift recoil-distance technique. Half-lives determined for the 2+, 4+, 6+, 2+', and 0+' states are 34.2±1.5, 7.3±0.4, 2.5±0.5, 7.3±0.6, and 37±8 ps, respectively. These states were Coulomb excited with 147-MeV Ar40 ions and measurements were performed in coincidence with the back-scattered projectiles. Comparisons of the experimental values with calculations from the rotational, vibrational, dynamic deformation, boson expansion, and interacting boson models show that the predictions of the latter two theories provide a reasonable overall description of this nucleus, but there are some discrepancies in interband transition strengths. In the course of this work the half-life of the 6+ state of Gd156 was also redetermined as 16.7±0.6 ps. NUCLEAR REACTIONS Gd152(Ar40,Ar′40,γ), E=147.2 MeV; measured lifetimes of 2+, 4+, 6+, 2+', and 0+' states; deduced B(E2) values, compared with theory.