A fresh look into nuclear shape coexistence: combining insights from the shell model and variational approaches

by Dr Javier Menendez Sanchez (University of Barcelona)

Thursday 31 Oct 2024, 11:00 → 13:00 Europe/Rome

C. Villi meeting room

Even though in the original naive shell-model proposed 75 years ago 28Si would correspond to a spherical nucleus because of the 0d5/2 closure, the 28Si ground state is deformed with an oblate shape. In addition, another deformed low-lying rotational bandhead appears at 7 MeV excitation energy, with a prolate shape. Furthermore, some heoretical calculations predict the appearance of superdeformed prolate states at low excitation energies.

In this seminar I will address the shape coexistence of oblate, prolate, normally-deformed and superdeformed states in 28Si. In order to do so, I will first take insights of the analytical quasi-SU(3) model and then use the nuclear shell model combining numerical diagonalizations complemented with variational calculations based on the projected generator-coordinate method. This multifaceted approach will allow a solid understanding of the low-lying structure of 28Si.