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

Low-momentum nucleon-nucleon interaction and shell-model calculations

We discuss the use of the low-momentum nucleon-nucleon NN interaction V-low-k in the derivation of the shell-model effective interaction and emphasize its practical value as an alternative to the Brueckner G-matrix method. We present some selected results of our current study of exotic nuclei around closed shells, which have been obtained starting from the CD-Bonn potential. We also show some results of calculations performed with different phase-shift equivalent NN potentials, and discuss the effect of changes in the cutoff momentum which defines the V-low-k potential.Comment: 5 pages, 5 figures, 1 table, Talk presented at CDN05, 31 Jan - 4 Feb 2005, University of Tokyo, Japa

Similarity of nuclear structure in 132Sn and 208Pb regions: proton-neutron multiplets

Starting from the striking similarity of proton-neutron multiplets in 134Sb and 210Bi, we perform a shell-model study of nuclei with two additional protons or neutrons to find out to what extent this analogy persists. We employ effective interactions derived from the CD-Bonn nucleon-nucleon potential renormalized by use of the V-low-k approach. The calculated results for 136Sb, 212Bi, 136I, and 212At are in very good agreement with the available experimental data. The similarity between 132Sn and 208Pb regions is discussed in connection with the effective interaction, emphasizing the role of core polarization effects.Comment: 4 pages, 3 figures, 2 table

Shell-model interpretation of high-spin states in 134-I

New experimental information has been recently obtained on the odd-odd nucleus 134-I. We interpret the five observed excited states up to the energy of ~3 MeV on the basis of a realistic shell-model calculation, and make spin-parity assignments accordingly. A very good agreement is found between the experimental and calculated energies.Comment: 3 pages, 1 figur

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

Fully microscopic shell-model calculations with realistic effective hamiltonians

The advent of nucleon-nucleon potentials derived from chiral perturbation theory, as well as the so-called V-low-k approach to the renormalization of the strong short-range repulsion contained in the potentials, have brought renewed interest in realistic shell-model calculations. Here we focus on calculations where a fully microscopic approach is adopted. No phenomenological input is needed in these calculations, because single-particle energies, matrix elements of the two-body interaction, and matrix elements of the electromagnetic multipole operators are derived theoretically. This has been done within the framework of the time-dependent degenerate linked-diagram perturbation theory. We present results for some nuclei in different mass regions. These evidence the ability of realistic effective hamiltonians to provide an accurate description of nuclear structure properties.Comment: 6 pages, 9 figures, talk presented at INPC2010, Vancouver, July 4 -9 2010. Accepted for publication in Journal of Physics: Conference Serie

Structure of exotic nuclei around double shell closures

In this paper, we first give a brief review of the theoretical framework for microscopic shell-model calculations starting from the free nucleon-nucleon potential. In this context, we discuss the use of the low-momentum nucleon-nucleon interaction V-low-k in the derivation of the shell-model effective interaction and emphasize its practical value as an alternative to the Brueckner G-matrix method. Then, we present some results of our current study of exotic nuclei around doubly magic 132Sn, which have been obtained starting from the CD-Bonn potential renormalized by use of the V-low-k approach. Attention is focused on the nuclei 134Te, 134Sn, and 136Te, in particular on the latter which is a direct source of information on the proton-neutron effective interaction in the 132Sn region. Comparison shows that our results are in very good agreement with the available experimental data.Comment: 8 pages, 3 figures, to be published in Prog. Part. Nucl. Phy

Effects of neutron-proton interaction in doubly odd deformed nuclei

We have investigated the effects of the neutron-proton interaction in several doubly odd deformed nuclei within the framework of the particle-rotor model. In this paper, we show some selected results of our study which evidence the importance of the tensor-force effects.Comment: Contributed paper at "High Spin Physics 2001", see http://www.fuw.edu.pl/~hs2001/, to be published in Acta Physica Polonica B, see http://th-www.if.uj.edu.pl/acta/index.htm