Speaker
Description
Study of nuclear structure around the magic numbers is key to understanding the chart of nuclei. The region around $^{78}$Ni is of interest, not only because it is one of the heavier doubly magic nuclei, but also because it has been proposed as a portal to the fifth island of inversion [Nowacki, F. et al. Phys. Rev. Lett. 117, 272501]. Evidence for low-lying shape coexistence near N=40 has been observed, but, until recently, no evidence of low-lying $0_{2}^{+}$ states in the Ge isotopes near N=50 had be reported. An experiment at the ALTO facility identified a $0_{2}^{+}$ state at 639 keV above the $0^{+}$ ground state in $^{80}$Ge [Gottardo, A. et al. Phys. Rev. Lett. 116, 182501]. However, $\beta$-decay studies using the GRIFFIN facility at TRIUMF, show no evidence for this state. Furthermore, the decay of a proposed (2$^{+}$) 2403-keV state to the $0^{+}_{2}$ 639-keV state was not observed, nor was there other evidence for this state. Large-scale shell model calculations were performed, using two different valence spaces and interactions, for $^{78,80,82}$Ge. These calculations were able to reproduce the energies of known $0_{2}^{+}$, $2_{1,2}^{+}$ and $4_{1}^{+}$ levels in these Ge isotopes. The $0_{2}^{+}$ state in $^{80}$Ge is predicted to be near 2 MeV and arises from the recoupling of valence particles. The search for this state, will be described, and the recently published findings [Garcia, F.H. et al. Phys. Rev. Lett. 125, 172501] will be presented.
| email address | fatimag@sfu.ca |
|---|---|
| Please select: Experiment or Theory | Experiment |
