Quasi-particle random phase approximation with quasi-particle-vibration   coupling: application to the Gamow-Teller response of the superfluid nucleus   $^{120}$Sn
  We propose a self-consistent quasi-particle random phase approximation (QRPA) plus quasi-particle-vibration coupling (QPVC) model with Skyrme interactions to describe the width and the line shape of giant resonances in open-shell nuclei, in which the effect of superfluidity should be taken into account in both the ground state and the excited states. We apply the new model to the Gamow-Teller resonance in the superfluid nucleus $^{120}$Sn, including both the isoscalar spin-triplet and the isovector spin-singlet pairing interactions. The strength distribution in $^{120}$Sn is well reproduced and the underlying microscopic mechanisms, related to QPVC and also to isoscalar pairing, are analyzed in detail. 
Y. F. Niu, G. Colo, E. Vigezzi, C. L. Bai, H. Sagawa
nucl-th