Speaker
Description
Driven by recent advances in the understanding of coexisting shapes in the even-even Ni isotopes, the structure of neighboring $^{68}$Zn was investigated using nuclear resonance fluorescence. Low-spin levels were excited using linearly polarized photon beams at energies ranging from 3 MeV to the particle threshold using the High Intensity $\gamma$-Ray Source (HI$\gamma$S). In addition, $\gamma-\gamma$ coincidence data enabled the study of the low-energy level scheme, populated from a high-energy and low-spin entrance point just below the particle emission threshold. The new data resulting from this work are interpreted in the shell-model picture in two different model spaces using several effective interactions. The distribution of $E1$ levels and $M1$ strength, paired with properties of the low-energy level scheme, reveal the involvement of a large number of orbitals active across a wide range of excitation energies in $^{68}$Zn. The coincidence capabilities of the Clover Array at HI$\gamma$S are explored, with highlights including the population of low-energy states with spins $J=0-4$ and the potential of lifetime measurements with the CeBr$_3$ scintillators.
This work is supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics, under Grants No. DE-FG02-97ER41041 (UNC), and No. DE-FG02-97ER41033 (TUNL), and by the U.S. National Science Foundation under Grant No. PHY-2110365 (FRIB, MSU).
