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arXiv · 1006.0059

Systematics of 2+ states in semi-magic nuclei

D. S. Delion·N. V. Zamfir
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Abstract

We propose a simple systematics of low lying 2+ energy levels and electromagnetic transitions in semi-magic isotopic chains Z=28,50,82 and isotonic chains N=28,50,82,126. To this purpose we use a two-level pairing plus quadrupole Hamiltonian, within the spherical Quasiparticle Random Phase Approximation (QRPA). We derive a simple relation connecting the 2+ energy with the pairing gap and quadrupole-quadupole (QQ) interaction strength. It turns out that the systematics of energy levels and B(E2) values predicted by this simple model is fulfilled with a reasonable accuracy by all available experimental data. Both systematics suggest that not only active nucleons but also those filling closed shells play an important role.

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D. S. Delion, N. V. Zamfir. 2010-06-01. Systematics of 2+ states in semi-magic nuclei. https://doi.org/10.1103/physrevc.82.031302

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