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arXiv · 1907.05493

Variational approximations to exact solutions in shell-model valence spaces: calcium isotopes in the pf-shell

B. Bally·A. Sánchez-Fernández·T. R. Rodríguez
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Abstract

We study the performance of self-consistent mean-field and beyond-mean-field approximations in shell-model valence spaces. In particular, Hartree-Fock-Bogolyubov, particle-number variation after projection and projected generator coordinate methods are applied to obtain ground-state and excitation energies for even-even and odd-even Calcium isotopes in the pf-shell. The standard (and non-trivial) KB3G nuclear effective interaction has been used. The comparison with the exact solutions -- provided by the full diagonalization of the Hamiltonian -- shows an outstanding agreement when particle-number and angular-momentum restorations are performed and both quadrupole and neutron-neutron pairing degrees of freedom are explicitly explored as collective coordinates.

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B. Bally, A. Sánchez-Fernández, T. R. Rodríguez. 2019-07-11. Variational approximations to exact solutions in shell-model valence spaces: calcium isotopes in the pf-shell. https://doi.org/10.1103/physrevc.100.044308

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