Shape coexistence and mixing of low-lying 0(+) states in Sr-96

The low energy excited 0(2,3)(+) states in Sr-96 are amongst the most prominent examples of shape coexistence across the nuclear landscape. In this work, the neutron [2s(1/2)](2) content of the 0(1,2,3)(+) states in Sr-96 was determined by means of the d(Sr-95,p) transfer reaction at the TRIUMF-ISAC2 facility using the SHARC and TIGRESS arrays. Spectroscopic factors of 0.19(3) and 0.22(3) were extracted for the Sr-96 ground and 1229 keV 0(+) states, respectively, by fitting the experimental angular distributions to DWBA reaction model calculations. A detailed analysis of the gamma-decay of the isomeric 0(3)(+) state was used to determine a spectroscopic factor of 0.33(13). The experimental results are compared to shell model calculations, which predict negligible spectroscopic strength for the excited 0(+) states in Sr-96. The strengths of the excited 0(2,3)(+) states were also analyzed within a two-level mixing model and are consistent with a mixing strength of a(2) = 0.40(14) and a difference in intrinsic deformations of vertical bar Delta beta vertical bar = 0.31(3). These results suggest coexistence of three different configurations in Sr-96 and strong shape mixing of the two excited 0(+) states. (C) 2018 The Author(s). Published by Elsevier B.V.