Collective T=0 pairing in N=Z nuclei? Pairing vibrations around 56Ni revisited

We present a new analysis of the pairing vibrations around 56 Ni, with emphasis on odd-odd nuclei. This analysis of the experimental excitation energies is based on the subtraction of average properties that include the full symmetry energy together with the volume, surface, and Coulomb terms. The results clearly indicate a collective behavior of the isovector pairing vibrations and do not support any appreciable collectivity in the isoscalar channel.