Effect of neutron halos on excited states of nuclei

The differential cross sections of the inelastic scattering leading to the excitation of short-lived states in the stable 13C and 9Be nuclei as well as the radioactive 11Be nucleus have been analyzed. Signatures of neutron halos in the excited states located close to the neutron emission thresholds have been investigated by applying a recently developed modified diffraction model. The abnormally large rms radius was identified for the 3.089-MeV 1/2+ state of 13C. Significantly enlarged diffraction radii were found for the 1.68-MeV 1/2+ and the 3.05-MeV 5/2+ states of 9Be. The analysis of the diffraction radii of the weakly bound radioactive 11Be nuclei have shown that the 1.78-MeV 5/2+ and 3.41-MeV 3/2+ states in 11Be have the same diffraction radii as the 1/2+ ground state, which is known as the best example of a state with one-neutron halo.