Speaker
Description
Understanding the mechanisms that cause nuclei in the ground or excited state to stabilize at certain shapes is pivotal to explaining structured evolution, especially far from closed shells. Rich systems for shape studies are found in the neutron-deficient A ≈ 80 region, around the N = Z nuclei $^{76}$Sr, $^{78}$Y, $^{80}$Zr, and $^{82}$Nb. Evidence from spectroscopic signatures indicates that the ground states of nuclei in this region are highly deformed. As such, there are opportunities to study deformation as well as contributions from the Wigner energy and pairing along the N = Z line. In this region, we used the Low Energy Beam and Ion Trap (LEBIT) Facility to measure the masses of $^{77,78,79}$Y, $^{79,80}$Zr and $^{82}$Nb to uncertainties <10 keV/c. This includes the first mass measurements of $^{77,78}$Y, $^{79}$Zr, and $^{82}$Nb as well as the first Penning trap measurements of $^{78m,79}$Y, which improve their precision by an order of magnitude. Additionally, the mass of $^{80}$Zr deviates from the previous LEBIT value [1], resulting in a major update to the surrounding region’s structure. These mass results and their implications will be presented.
[1] A. Hamaker, et al., Nat. Phys. 17, 1408–1412 (2021)