Quenching of N = 28 shell gap and a low-lying quadrupole mode in the vicinity of neutron-rich N = 28 isotones

2014/08/10 by Shuichiro Ebata, Masaaki Kimura, Ebata, Shuichiro +1
Chemistry · Physics and Astronomy · #Advanced Chemical Physics Studies #FOS: Physical sciences #Inorganic Fluorides and Related Compounds #Nuclear Theory (nucl-th) #Nuclear physics research studies #nucl-th

paper · pdf · doi:10.48550/arxiv.1408.2221

Advances in Radioactive Isotope Science (ARIS2014) conference proceedings, 4 page, 2 figures

openalex publication_date 2014/08/10 · arxiv created 2015/01/21 · arxiv updated 2015/01/22 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

We investigate the low-lying 2⁺ states of N=28 isotones (⁴⁸Ca, ⁴⁶Ar, ⁴⁴S and ⁴²Si) with using the canonical-basis time-dependent Hartree-Fock-Bogoliubov theory in which the pairing is taken into account self-consistently. The quadrupole mode with very small excitation energies emerges in ⁴⁶Ar, ⁴⁴S and ⁴²Si due to the strong quadrupole correlations triggered by the quenching of the N=28 shell gap. The importance of the quadrupole correlations between the protons and neutrons, and the role of the pairing correlation to reinforce the lowest 2⁺ mode are discussed. It is also shown that the B(E2\uparrow) values of ⁴⁸Ca and ⁴⁶Ar are plausibly explained by our calculations.

Related

• Erosion of N = 28 shell closure: Shape coexistence and monopole transition
• Effects of ground-state correlations on dipole and quadrupole excitations of ⁴⁰Ca and ⁴⁸Ca
• Evolution of shell structure at N=32 and 34: Insights from realistic nuclear forces
• np-nh bands in the N=28 isotones
• Large scale shell model calculation for collectivity in nuclei beyond 78Ni