Abstract
We study the effects of the coupling between one- and two-phonon components of the wave functions on the low-energy electric dipole response of 68Ni in a microscopic model based on an effective Skyrme interaction SLy5. The finite rank separable approach for the quasiparticle random phase approximation is used. The effect of phonon-phonon coupling leads to the fragmentation of the \(E1\) strength to a lower energy and improves the agreement with available experimental data.
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Arsenyev, N.N., Severyukhin, A.P., Voronov, V.V. et al. Low-Energy E1 Strength Distributions of 68Ni. Phys. Part. Nuclei 50, 528–531 (2019). https://doi.org/10.1134/S1063779619050034
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DOI: https://doi.org/10.1134/S1063779619050034