Quartet correlations in N=Z nuclei induced by realistic two-body interactions

Abstract

Two variational quartet models previously employed in a treatment of pairing forces are extended to the case of a general two-body interaction. One model approximates the nuclear states as a condensate of identical quartets with angular momentum $J=0$ and isospin $T=0$ while the other let these quartets to be all different from each other. With these models we investigate the role of alpha-like quartet correlations both in the ground state and in the lowest $J=0$, $T=0$ excited states of even-even $N=Z$ nuclei in the $sd$-shell. We show that the ground state correlations of these nuclei can be described to a good extent in terms of a condensate of alpha-like quartets. This turns out to be especially the case for the nucleus ${}^{32}$S for which the overlap between this condensate and the shell model wave function is found close to one. In the same nucleus, a similar overlap is found also in the case of the first excited $0^{+}$ state. No clear correspondence is observed instead between the second excited states of the quartet models and the shell model eigenstates in all the cases examined.

10 pages, to appear in EPJ A

References in corpus (6)

• Mixed-Spin Pairing Condensates in Heavy Nuclei
• Isoscalar and isovector pairing in a formalism of quartets
• Four-body correlations in nuclei
• Isovector proton-neutron pairing and Wigner energy in Hartree-Fock mean field calculations
• Isovector pairing in a formalism of quartets for N=Z nuclei
• Isoscalar-isovector proton-neutron pairing and quartet condensation in N=Z nuclei

Cited by in corpus (12)

• A quartet BCS-like theory
• $\alpha$-like quartetting in the excited states of proton-neutron pairing Hamiltonians
• Analytical approach for the Quartet Condensation Model
• Band-like structures and quartets in deformed N=Z nuclei
• Pairing correlations and eigenvalues of two-body density matrix in atomic nuclei
• Disentangling the pair and quartet condensates
• Unified description of pairing and quarteting correlations within the particle-hole-boson approach
• Quartet structure of $N=Z$ nuclei in a boson formalism: the case of ${}^{28}$Si
• Collective treatment of the isovector pair correlations. Boson representation
• Coexistence of quartets and pairs in even-even $N>Z$ nuclei
• Structure of the quartetting ground state of $N=Z$ nuclei
• Quartet condensation induced by the isovector pairing force