Realistic Shell-Model Calculations for Nuclei in the Region of Shell Closures off Stability

We have performed realistic shell-model calculations for nuclei around doubly magic 100Sn and 132Sn using an effective interaction derived from the Bonn A nucleon-nucleon potential. The results are in remarkably good agreement with the experimental data showing the ability of our effective interaction to provide an accurate description of nuclear structure properties.Comment: 6 pages, 6 figures, Proceedings of the SNEC98 Conference, to be published on Nuovo Cimento

Structure of particle-hole nuclei around 100Sn

We have performed shell-model calculations for the three odd-odd nuclei 100In, 102In, and 98Ag, with neutron particles and proton holes around 100Sn. We have used a realistic effective interaction derived from the CD-Bonn nucleon-nucleon potential, the neutron-proton channel being explicitly treated in the particle-hole formalism. Particular attention has been focused on the particle-hole multiplets, which are a direct source of information on the neutron-proton effective interaction. We present our predictions for the two lowest lying multiplets in 100In, for which no spectroscopic data are yet available. For 98Ag and 102In comparison shows that our results are in very good agreement with the available experimental data.Comment: 5 pages, published in Physical review

Evolution of single-particle states beyond 132^{132}Sn

We have performed shell-model calculations for the two one valence-neutron isotones $^{135}$Te and $^{137}$Xe and the two one valence-proton isotopes $^{135,137}$Sb. The main aim of our study has been to investigate the evolution of single-particle states with increasing nucleon number. To this end, we have focused attention on the spectroscopic factors and the effective single-particle energies. In our calculations, we have employed a realistic low-momentum two-body effective interaction derived from the CD-Bonn nucleon-nucleon potential that has already proved quite successful in describing the spectroscopic properties of nuclei in the $^{132}$Sn region. Comparison shows that our results reproduce very well the available experimental data. This gives confidence in the evolution of the single-particle states 4 figures predicted by the present study.Comment: 7 pages, 4figures, submitted to Phys. Rev.

Structure of Neutron-Rich Nuclei in the 132Sn Region

We report on a study of neutron-rich nuclei around 132Sn in terms of the shell model employing a realistic effective interaction derived from the CD-Bonn nucleon-nucleon potential. We present results for some Sb and Te isotopes. Comparison shows that our results are in very good agreement with the available experimental data supporting confidence in the predictions of our calculations. This may stimulate experimental efforts to gain more information on these nuclei lying well away from the valley of stability.Comment: 9 pages, 5 figure, talk presented at the 3rd International Conference on Fission and Properties of Neutron-Rich Nuclei, Sanibel Island, Florida, November 3-9 200

Fully Microscopic Calculations for Closed-Shell Nuclei with Realistic Nucleon-Nucleon Potentials

The ground-state energy of the doubly magic nuclei 4He and 16O has been calculated within the framework of the Goldstone expansion starting from modern nucleon-nucleon potentials. A low-momentum potential V-low-k has been derived from the bare potential by integrating out its high-momentum components beyond a cutoff Lambda. We have employed a simple criterion to relate this cutoff momentum to a boundary condition for the two-nucleon model space spanned by a harmonic-oscillator basis. Convergence of the results has been obtained with a limited number of oscillator quanta.Comment: 8 pages, 5 figures, talk given at 11th Conference on Problems in Theoretical Nuclear Physics, Cortona, Italy, 11-14 October 200

Behavior of odd-even mass staggering around 132Sn

We have performed shell-model calculations of binding energies of nuclei around $^{132}$Sn. The main aim of our study has been to find out if the behavior of odd-even staggering across N=82 is explainable in terms of the shell model. In our calculations, we have employed realistic low-momentum two-body effective interactions derived from the CD-Bonn nucleon-nucleon potential that have already proved quite successful in describing the spectroscopic properties of nuclei in the $^{132}$Sn region. Comparison shows that our results fully explains the trend of the experimental staggering.Comment: 3 pages, 1 figur

Proton-neutron multiplets in exotic 134Sb: testing the shell-model effective interaction

The experimental level structure of 134Sb is compared with the results of a shell-model calculation in which the two-body matrix elements of the effective interaction have been derived from the CD-Bonn nucleon-nucleon potential. The experimental data, including the very low-lying first-excited 1- state, are remarkably well reproduced by the theory. The results of this paper complement those of our previous studies on 135Sb and 134Sn, showing that our effective interaction is well suited to describe 132Sn neighbors beyond N=82. The various terms which contribute to the matrix elements of the proton-neutron effective interaction are examined and their relative importance is evidenced.Comment: 4 pages, 3 figures, published on Physical Review