Effects of surface vibrations on quadrupole response of nuclei
  The effect of quadrupole-type surface vibrations on the quadrupole response function of heavy nuclei is studied by using a model based on the solution of the linearized Vlasov equation with moving-surface boundary conditions. By using a separable approximation for the residual interaction, an analytical expression is obtained for the moving-surface response function. Comparison of the fixed- and moving-surface strength functions shows that surface vibrations are essential in order to achieve a unified description of the two characteristic features of the quadrupole response: the giant resonance and the low-lying states. Calculations performed by setting the surface tension equal to zero shows that the low-lying strength is strongly affected by the surface tension. 
V.I.Abrosimov (1), A.Dellafiore (2) and F.Matera (2) ((1) Institute   for Nuclear Research, Kiev, Ukraine, (2) INFN and Dipa...