Halo structure of 11Li in proton scattering: A folding model description with isospin, density and momentum dependent effective interaction

Abstract

Recent 11Li+p elastic scattering data at 62, 68.4, and 75 MeV and inelastic scattering data at 68.4 MeV, taken at RIKEN, are analysed with an isospin, density and momentum dependent finite range effective interaction (SBM) and M3Y interaction in a single folding model. The M3Y folded 11Li+p potentials are found to be almost similar to the folded 9Li+p potentials. But the SBM folded 11Li+p potentials are distinctly different, causing small but significant change in the angular distribution. Folded potentials need appreciable reduction factors indicating possible effects of strong breakup channel coupling. No significant change in results is found if 9Li core + Gaussian two-neutron halo density is used instead of the COSM density of 11Li although the radial extent of the latter is much larger. The angular distribution of the recently discovered excited state at 1.3 MeV, well reproduced by the SBM folded potential, is found to be predominantly dipole in nature.