Low-Energy E1 Strength Distributions of 68Ni

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.