$N=Z$ nuclei: A laboratory for neutron-proton collective mode

Abstract

The neutron-neutron and proton-proton pairing correlations have long been recognised to be the dominant many-body correlation beyond the nuclear mean field since the introduction of pairing mechanism by Bohr, Mottelson and Pines nearly 60 year ago. Nevertheless, few conclusion has been reached concerning the existence of analogous neutron-proton (np) pair correlated state. One can see a renaissance in np correlation studies in relation to the significant progress in radioactive ion beam facilities and detection techniques. The np pairs can couple isospin T = 1 (isovector) or 0 (isoscalar). In the isovector channel, the angular momentum zero component is expected to be the most importance one. On the other hand, as one may infer from the general properties of the np two-body interaction, in the isoscalar channel, both the np pairs with minimum (J=1) and maximum (J=2j) spin values can be important. In this contribution, we will discuss the possible evidence for np pair coupling from different perspective and analyze its influence on interesting phenomena including the Wigner effect and mass correlations in odd-odd nuclei. In particular, we will explain the spin-aligned pair coupling scheme and quartet coupling involving pairs with maximum (J=2j) spin values.

19 pages,15 figures

References in corpus (21)

• Global performance of covariant energy density functionals: ground state observables of even-even nuclei and the estimate of theoretical uncertainties
• Microscopic mechanism of charged-particle radioactivity and generalization of the Geiger-Nuttall law
• Overview of Neutron-Proton Pairing
• Evidence for a spin-aligned neutron-proton paired phase from the level structure of ${}^{92}$Pd
• Mixed-Spin Pairing Condensates in Heavy Nuclei
• Empirical Proton-Neutron Interactions and Nuclear Density Functional Theory: Global, Regional and Local Comparisons
• Proton-Neutron Pairing Amplitude as a Generator Coordinate for Double-Beta Decay
• On the Validity of the Geiger-Nuttall Alpha-Decay Law and its Microscopic Basis
• Spin-aligned neutron-proton pairs in $N=Z$ nuclei
• Isospin Dependence in the Odd-Even Staggering of Nuclear Binding Energies
• Partial conservation of seniority in $j=9/2$ shell: Analytic and numerical studies
• Double binding energy differences: Mean-field or pairing effect?
• Energy expressions for n=3 and 4 systems in a single-j shell
• What can be learned from binding energy differences about nuclear structure: the example of delta V_{pn}
• Neutron-Proton pairing revisited
• Deformation effects on the coexistence between neutron-proton and particle like pairing in N=Z medium mass nuclei
• Analytic proof of partial conservation of seniority in $j=9/2$ shells
• Symplectic group structure of the 48Cr, 88Ru, and 92Pd ground states
• Global phenomenological descriptions of nuclear odd-even mass staggering
• Proton and neutron correlations in ${}^{10}$B
• Whence the odd-even staggering in nuclear binding?

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• The $\beta$-decay properties of $N=Z$ nuclei: Role of neutron-proton pairing and the shell model interpretation
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