Physics Division Heavy Ion Discussion, March 16, 2023, held at 10 a.m. CST
Nirupama Sensharma, University of North Carolina at Chapel Hill
Nuclear structure physics from a multidimensional approach
Motivated by a growing interest in the structure of neutron-rich nuclei in the A~60 region, a detailed spectroscopic study for the odd-odd 62Co and its neighboring 66Zn and 64Cu nuclei have been performed. Using the Gammasphere array coupled to the Fragment Mass Analyzer, excited states in these nuclei were populated and extensive level schemes were developed. Spherical shell model and quantum particle-rotor model calculations have been performed to study the underlying nuclear structure and the evolution from single-particle excitations at low spins to well-deformed structures at high spins has been investigated. In the second part of the talk, the electromagnetic properties of low-lying states in 74,70Ge populated using a multi-step Coulomb excitation measurement carried out at the ATLAS facility of the Argonne National Laboratory will be presented. The experimental setup consisted of the GRETINA multidetector array coupled to the heavy-ion counter, CHICO2. The quadrupole collectivity and triaxiality of the ground-state and the quasi-gamma bands have been investigated in the framework of the spherical shell model, and the generalized triaxial rotor model. Preliminary results from the analysis will be presented in the context of similar studies performed for the neighboring 72,76Ge nuclei. Finally, results from a fusion-evaporation reaction to investigate the chiral rotation mode in the triaxial 135Pr nucleus will be presented. Using a high statistics Gammasphere experiment, the very first observation of co-existing chiral and wobbling modes has been made in this nucleus. Theoretical calculations in the framework of the quasiparticle triaxial rotor model will also be discussed.