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Origin of $2_1^+$ Excitation Energy Dependence on Valence Nucleon Numbers

Eunja Ha·Dongwoo Cha
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Abstract

It has been shown recently that a simple formula in terms of the valence nucleon numbers and the mass number can describe the essential trends of excitation energies of the first $2^+$ states in even-even nuclei. By evaluating the first order energy shift due to the zero-range residual interaction, we find that the factor which reflects the effective particle number participating in the interaction from the Fermi orbit governs the main dependence of the first $2^+$ excitation energy on the valence nucleon numbers.

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Eunja Ha, Dongwoo Cha. 2007-04-17. Origin of $2_1^+$ Excitation Energy Dependence on Valence Nucleon Numbers. https://doi.org/10.1103/physrevc.75.057304

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