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arXiv · 1502.05822

Shell-model study of quadrupole collectivity in light tin isotopes

L. Coraggio·A. Covello·A. Gargano·N. Itaco·T. T. S. Kuo
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Abstract

A realistic shell-model study is performed for neutron-deficient tin isotopes up to mass A=108. All shell-model ingredients, namely two-body matrix elements, single-particle energies, and effective charges for electric quadrupole transition operators, have been calculated by way of the many-body perturbation theory, starting from a low-momentum interaction derived from the high-precision CD-Bonn free nucleon-nucleon potential. The focus has been put on the enhanced quadrupole collectivity of these nuclei, which is testified by the observed large B(E2;0+ -> 2+)s. Our results evidence the crucial role played by the Z=50 cross-shell excitations that need to be taken into account explicitly to obtain a satisfactory theoretical description of light tin isotopes. We find also that a relevant contribution comes from the calculated neutron effective charges, whose magnitudes exceed the standard empirical values. An original double-step procedure has been introduced to reduce effectively the model space in order to overcome the computational problem.

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L. Coraggio, A. Covello, A. Gargano, N. Itaco, T. T. S. Kuo. 2015-04-13. Shell-model study of quadrupole collectivity in light tin isotopes. https://doi.org/10.1103/physrevc.91.041301

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