Break-up effect on the elastic scattering and the optical potential ofLi11

The elastic scattering of weakly bound projectiles such as deuteron and ${}_{}{}^{11}{}_{}{}^{}\mathrm{Li}$ nucleus are examined including the break-up process to the continuum excited states. The eikonal approximation is employed to derive the optical potential which includes the dynamical polarization potential due to the break-up process. The dynamical polarization potential is realized to be closely related to the fluctuation of the constituents of the projectile nucleus in its ground state. Strong effect of the break-up process on the ${}_{}{}^{11}{}_{}{}^{}\mathrm{-}_{}^{12}{}_{}{}^{}$C optical potential is found, which is qualitatively similar to those known for the deuteron optical potential. The elastic scattering differential cross section for ${}_{}{}^{11}{}_{}{}^{}\mathrm{-}_{}^{12}{}_{}{}^{}$C is calculated with the obtained optical potential. It is found that the scattering cross section decreases rapidly for large scattering angle compared with the ${}_{}{}^9{}_{}{}^{}\mathrm{Li}$ elastic scattering.