A comparison of Woods-Saxon and double-folding potentials for lithium scattering from light target nuclei

Abstract

Elastic scattering data are presented for 6Li at 36 MeV from 12O and 26Mg and for 7Li at 28.8 MeV from 15N and at 27 MeV from 25Mg over the range 15-95 degrees in the centre-of-mass frame. Microscopic optical potentials are generated for these scattering systems using the double-folding model. The sensitivity of the potentials to the prescriptions used for the nuclear density calculations is studied. The elastic scattering data are analysed within the framework of the optical model using both Woods-Saxon potentials and double-folding model real potentials with Woods-Saxon imaginary wells. Equally good fits to the data are obtained with the phenomenological and microscopic potentials. The double-folding potentials must be normalised by factors of 0.5 or 0.6 to fit the data in all cases except for 6Li scattering from 16O, for which a normalisation of 0.8 is favoured. These results are supplemented by those from an inelastic scattering analysis using DWBA and the collective rotational model for the first 2+ states in 12C and 26Mg. The shapes of the phenomenological and microscopic potentials around the strong absorption radius are compared and the gradients are found to differ significantly for 7Li+15N and 6Li+12C systems.