Exact solution of the pairing problem for spherical and deformed systems

Abstract

There has been increasing interest in studying the Richardson model from which one can derive the exact solution for certain pairing Hamiltonians. However, it is still a numerical challenge to solve the nonlinear equations involved. In this paper we tackle this problem by employing a simple hybrid polynomial approach. The method is found to be robust and is valid for both deformed and nearly spherical nuclei. It also provides important and convenient initial guesses for spherical systems with large degeneracy. As an example, we apply the method to study the shape coexistence in neutron-rich Ni isotopes.

arXiv comment5 pages, 6 figures

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Cited by in corpus (8)

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• Inner products in integrable Richardson-Gaudin models
• A variational method for integrability-breaking Richardson-Gaudin models
• Exact isovector pairing in a shell-model framework: Role of proton-neutron correlations in isobaric analog states
• PairDiagSph: Generalization of the Exact Pairing Diagonalization Program for Spherical Systems
• An exact solution of spherical mean-field plus orbit-dependent non-separable pairing model with two non-degenerate j-orbits
• Large-scale configuration interaction description of the structure of nuclei around ${}^{100}$Sn and ${}^{208}$Pb
• Models for Pairing Phenomena