Shape-coexistence studies in the Ni isotopic chain by using the selectivity of different reaction mechanisms
Articolo
Data di Pubblicazione:
2020
Citazione:
Shape-coexistence studies in the Ni isotopic chain by using the selectivity of different reaction mechanisms / S. Leoni, B. Fornal, N. Marginean, C. Michelagnoli, J. Wilson, M. Sferrazza, Y. Tsunoda, T. Otsuka. - In: ACTA PHYSICA POLONICA B. - ISSN 0587-4254. - 51:3(2020), pp. 807-815. [10.5506/APhysPolB.51.807]
Abstract:
We report on the investigation of the shape coexistence phenomenon in the Ni isotopic chain, from A = 62 to A = 66, by using γ-ray spectroscopy techniques and different reaction mechanisms, such as sub-Coulomb barrier transfer reactions and thermal-neutron capture. Our aim is to understand, from the microscopic point of view, the appearance of nuclear deformation in Ni isotopes at low excitation energy. A series of experiments was performed at the Tandem Accelerator Laboratory in Bucharest, at ALTO IPN-Orsay and at the ILL reactor in Grenoble. Various mean-field theoretical approaches, as well as recent state-of-the-art Monte Carlo Shell Model (MCSM) calculations, predict in 66Ni a deep secondary prolate minimum in the nuclear potential energy surface at spin zero, resulting in a hindered electromagnetic decay towards the spherical ground state (i.e., with an E2 transition probability less than 1 W.u.). This has been confirmed in the first experiment performed in Bucharest. Less pronounced prolate minima, at higher excitation energies, are also expected in lighter neutron-rich Ni isotopes, from state-of-the-art Monte Carlo Shell Model (MCSM) calculations. Preliminary results are discussed for 62Ni and 64Ni, in comparison with theory predictions.
Tipologia IRIS:
01 - Articolo su periodico
Keywords:
isomerism
Elenco autori:
S. Leoni, B. Fornal, N. Marginean, C. Michelagnoli, J. Wilson, M. Sferrazza, Y. Tsunoda, T. Otsuka
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