Phonon–particle coupling effects in odd–even double mass differences of magic nuclei

Abstract

A method is developed to consider the particle–phonon coupling (PC) effects in the problem of finding odd–even double mass differences (DMD) of magic nuclei within the approach starting from the free NN potential. Three PC effects are taken into account, the phonon induced interaction, the renormalization of the “ends” due to the Z-factors and the change of the single-particle energies. We use the perturbation theory in g_L², where g_L is the vertex of the L-phonon creation. PC corrections to single-particle energies are found selfconsistently. In addition to the usual pole diagram, the phonon “tadpole” diagram is taken into account approximately. Results for double-magic ¹³²Sn and ²⁰⁸Pb nuclei show that the PC corrections make agreement with the experimental data better.