Structure of the vacuum states in the presence of isovector and isoscalar pairing correlations

Abstract

The long standing problem of proton-neutron pairing and, in particular, the limitations imposed on the solutions by the available symmetries, is revisited. We look for solutions with non-vanishing expectation values of the proton, the neutron and the isoscalar gaps. For an equal number of protons and neutrons we find two solutions where the absolute values of proton and neutrons gaps are equal but have the same or opposite sign. The behavior and structure of these solutions differ for spin saturated (single l-shell) and spin unsaturared systems (single j-shell). In the former case the BCS results are checked against an exact calculation.

19 pages, 5 postscript figures

References in corpus (2)

• Boson mappings and four-particle correlations in algebraic neutron-proton pairing models
• Perturbative description of nuclear double beta decay transitions

Cited by in corpus (5)

• Local Density Approximation for proton-neutron pairing correlations. I. Formalism
• Overview of Neutron-Proton Pairing
• Isovector neutron-proton pairing with particle number projected BCS
• Properties of isocalar-pair condensates
• Pairing in 4-component fermion systems: the bulk limit of SU(4)-symmetric Hamiltonians