Lifetimes of negative parity yrast states in ¹²⁹Cs

The complex nature of nuclei – with many different structures – poses a challenge in nuclear spectroscopy. In nuclei near mass region 130, the proton Fermi surface lies in the lower part of the h_11/2 subshell which tends to drive nuclei to prolate shape (γ ∼ 0°), while the neutron Fermi surface in the middle or upper part of the h_11/2 subshell tends to oblate shape (γ ∼ −60°). Measurement of lifetimes of nuclear states constitutes an indispensable probe into the microscopic structure of nuclei. Wang et al. measured the lifetimes of the states of ¹²⁹Cs using a ¹²⁴Sn thick target with backing, while Sihotra et al. established the decay scheme. In the present study, we have extracted the precise lifetimes using a thick target which acted as a backing also. Besides, we have lifetime results for more states in ¹²⁹Cs compared to previous work