Double-step truncation procedure for large-scale shell-model calculations

Abstract

We present a procedure that is helpful to reduce the computational complexity of large-scale shell-model calculations, by preserving as much as possible the role of the rejected degrees of freedom in an effective approach. Our truncation is driven first by the analysis of the effective single-particle energies of the original large-scale shell-model hamiltonian, so to locate the relevant degrees of freedom to describe a class of isotopes or isotones, namely the single-particle orbitals that will constitute a new truncated model space. The second step is to perform an unitary transformation of the original hamiltonian from its model space into the truncated one. This transformation generates a new shell-model hamiltonian, defined in a smaller model space, that retains effectively the role of the excluded single-particle orbitals. As an application of this procedure, we have chosen a realistic shell-model hamiltonian defined in a large model space, set up by seven and five proton and neutron single-particle orbitals outside 88Sr, respectively. We study the dependence of shell-model results upon different truncations of the original model space for the Zr, Mo, Ru, Pd, Cd, and Sn isotopic chains, showing the reliability of this truncation procedure.

10 pages, 15 figures, to be published in Physical Review C

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Cited by in corpus (13)

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• Shell-model calculation of ${}^{100}$Mo double-$\beta$ decay
• Calculation of Gamow-Teller and Two-Neutrino Double-Beta Decay Properties for 130Te and 136Xe with a realistic nucleon-nucleon potential
• Perturbative Approach to Effective Shell-Model Hamiltonians and Operators
• Multi-channel experimental and theoretical constraints for the ${}^{116}$Cd(${}^{20}$Ne,${}^{20}$F)${}^{116}$In charge exchange reaction at 306 MeV
• One-neutron transfer reaction in the ${}^{18}$O + ${}^{48}$Ti collision at 275 MeV
• Systematic reduction of the proton-removal cross section in neutron-rich medium-mass nuclei
• Shell-model study of titanium isotopic chain with chiral two- and three-body forces
• Monopole and Seniority Truncations in the Large-Scale Configuration Interaction Shell Model Approach
• Large scale shell model calculation for collectivity in nuclei beyond 78Ni
• Neutrinoless Double-Beta Decay and Realistic Shell Model
• A glimpse into an effective world