Alpha-like quartet condensation and isovector pairing correlations in N=Z nuclei

Abstract

We propose a simple quartet condensation model (QCM) which describes with very high accuracy the isovector pairing correlations in self-conjugate nuclei. The quartets have an alpha-like structure and are formed by collective isovector pairs. The accuracy of the QCM is tested for N=Z nuclei for which exact shell model diagonalizations can be performed. The calculations are done with two isovector pairing forces, one extracted from standard shell model interactions and the other of seniority type, acting, respectively, upon spherical and axially-deformed single-particle states. It is shown that for all calculated nuclei the QCM gives very accurate values for the pairing correlations energies, with errors which do not exceed 1%. These results show clearly that the correlations induced by the isovector pairing in self-conjugate nuclei are of quartet type and also indicate that QCM is the proper tool to calculate the isovector proton-neutron correlations in mean field pairing models.

11 pages, two tables

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Cited by in corpus (36)

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• Isovector pairing in a formalism of quartets for N=Z nuclei
• A quartet BCS-like theory
• Deformation effects on the coexistence between neutron-proton and particle like pairing in N=Z medium mass nuclei
• Isoscalar-isovector proton-neutron pairing and quartet condensation in N=Z nuclei
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• Treatment of like-particle pairing with quartets
• Quartetting in odd-odd self-conjugate nuclei
• Bridging the quartet and pair pictures of isovector proton-neutron pairing
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• $\alpha$-like quartetting in the excited states of proton-neutron pairing Hamiltonians
• Stability against three-body clustering in one-dimensional spinless p-wave fermions
• 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
• Competition between pairing and tripling in one-dimensional fermions with coexistent s- and p-wave interactions
• Disentangling the pair and quartet condensates
• Integrable Model of Topological SO(5) Superfluidity
• Unified description of pairing and quarteting correlations within the particle-hole-boson approach
• Quartet correlations near the surface of $N=Z$ nuclei
• Collective treatment of the isovector pair correlations. Boson representation
• Cooper pairing and tripling in one-dimensional spinless fermions with attractive two- and three-body forces
• Quartet structure of $N=Z$ nuclei in a boson formalism: the case of ${}^{28}$Si
• Polaronic neutron in dilute alpha matter: A $p$-wave Bose polaron
• Structure of the quartetting ground state of $N=Z$ nuclei
• Coexistence of quartets and pairs in even-even $N>Z$ nuclei
• Isovector pair correlations in analytically solvable models
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• Collective model with isovector pair and alpha-particle type correlations
• Mass-imbalance effect on the cluster formation in a one-dimensional Fermi gas with coexistent $s$- and $p$-wave interactions