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Dipole states in stable and unstable nuclei

D. Sarchi·P. F. Bortignon·G. Colo`
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Abstract

A nuclear structure model based on linear response theory (i.e., Random Phase Approximation) and which includes pairing correlations and anharmonicities (coupling with collective vibrations), has been implemented in such a way that it can be applied on the same footing to magic as well as open-shell nuclei. As applications, we have chosen to study the dipole excitations both in well-known, stable isotopes like $^{208}$Pb and $^{120}$Sn as well as in the neutron-rich, unstable $^{132}$Sn nucleus, by addressing in the latter case the question about the nature of the low-lying strength. Our results suggest that the model is reliable and predicts in all cases low-lying strength of non collective nature.

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D. Sarchi, P. F. Bortignon, G. Colo`. 2004-06-24. Dipole states in stable and unstable nuclei. https://doi.org/10.1016/j.physletb.2004.09.019

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