Abstract
Large-scale shell-model calculations predict that the region of deformation which comprises the heaviest chromium and iron isotopes at and beyond will merge with a new one at in an astonishing parallel to the and case in the neon and magnesium isotopes. We propose a valence space including the full shell for the protons and the full shell for the neutrons, which represents a comeback of the the harmonic oscillator shells in the very neutron- rich regime. The onset of deformation is understood in the framework of the algebraic SU(3)-like structures linked to quadrupole dominance. Our calculations preserve the doubly magic nature of the ground state of , which, however, exhibits a well-deformed prolate band at low excitation energy, providing a striking example of shape coexistence far from stability. This new IOI adds to the four well-documented ones at , 20, 28, and 40.
- Received 30 May 2016
DOI:https://doi.org/10.1103/PhysRevLett.117.272501
© 2016 American Physical Society