Proton-neutron structure of first and second quadrupole excitations of 90Sr

Abstract

Starting from the Skyrme interaction $f_{-}$ together with the density-dependent pairing interaction, we study the g factors for the $2_{1,2}^{+}$ excitations of 88, 90Sr and 90, 92Zr. The coupling between one- and two-phonon terms in the wave functions of excited states is taken into account within the finite-rank separable approximation. Using the same set of parameters we describe available experimental data and give the prediction for 90Sr, $g(2_{2}^{+})=+0.03$ in comparison to $ +0.31$ in the case of 92Zr.