The elastic-scattering angular distribution of p${+}^{11}$Li at ${\mathit{E}}_{\mathrm{lab}}$=100 MeV is evaluated within Glauber’s theory. The p${\mathrm{-}}^{11}$Li optical potential is evaluated within the ‘‘tρ’’ approximation with ${\mathrm{\rho }}^{11}$Li, the matter density of ${}_{}{}^{11}{}_{}{}^{}\mathrm{Li}$, calculated within constrained Hartree-Fock theory. Medium effects on the nucleon-nucleon t matrix, are fully taken into account. The effect of the halo neutrons on dσ/dΩ is assessed through comparison with the p${+}^{12}$C and p${+}^9$Li systems at ${\mathit{E}}_{\mathrm{lab}}$=100 and 800 MeV.

• Received 22 October 1990

DOI:https://doi.org/10.1103/PhysRevC.43.2722