Exploring the Puzzle of Decay Half-lives Southeast of $^{\mathrm{132}}$Sn

The region of nuclei around doubly magic $^{132}$Sn [1] offers a unique window to study nuclear structure. Calculations in the region are used to provide the nuclear parameters in models of isotope productions in stellar rapid neutron capture (r-process) [2]. However, recent measurements of the decay half-lives in the region show systematic discrepancies with shell model calculations[3]. The beta decay of $^{132}$Cd was studied at the ISOLDE facility, CERN. The large majority of the beta-decay strength was expected to populate the unbound lowest-energy 1$^+$ state [2]. The neutron time-of-flight array VANDLE [4,5] was installed at the ISOLDE decay station. Large Gamow-Teller strength was observed in the neutron time-of-flight spectra. Analysis of the data indicates several individual 1+ states are fed in $^{132}$In. Strength fragmentation offers a compelling explanation for the experimental half-life of $^{132}$Cd being longer than state-of-the-art calculations [2]. [1] K.L. Jones et al., Nature 465, 454 (2010). [2] P. Möller, B. Pfeiffer, and K.-L. Kratz, Phys. Rev. C67,055802 (2003). [3] G. Lorusso et al., Phys. Rev. Lett. 114, 192501 (2015). [4] W. A. Peters et al., Nucl. Inst. Meth. A836, 122 (2016). [5] S.V . Paulauskas et al., Nucl. Instrum Meth. A737, 22 (2014).