Speaker
Nancy Paul
(CEA Saclay)
Description
A predicted Z=40 subshell closure in Zr has long been considered a potential explanation for the excess of elemental abundances before the A=130 r-process peak. We performed the first spectroscopy of this nucleus at the RIKEN-RIBF facility, populating the low-lying levels via (p,2p) knockout and measuring the energies with the MINOS tracker and DALI2 NaI array. We will present first spectroscopy results, Nb(p,2p) Zr and Mo(p,3p) Zr cross sections, complementary analysis of neighboring nuclei, implications for structural evolution in the 50 N 82 region, and the impact on our understanding of the formation of the A=130 r-process peak. Additionally, we report on a broader, ongoing study of (p,2p) and (p,3p) quasi-free scattering cross sections as measured during the SEASTAR (Shell Evolution And Search for Two-plus energies At RIBF) campaigns.
Primary author
Nancy Paul
(CEA Saclay)
Co-author
Shell Evolution And Search for Two-plus energies At RIKEN The SEASTAR Collaboration
(CEA Saclay)