Role of breakup processes in fusion enhancement of drip-line nuclei at energies below the Coulomb barrier

We carry out realistic coupled-channel calculations for the ${}^{11}\mathrm{Be}{+}^{208}\mathrm{Pb}$ reaction in order to discuss the effects of breakup of the projectile nucleus on subbarrier fusion. We discretize in energy the particle continuum states, which are associated with the breakup process, and construct the coupling form factors to these states on a microscopic basis. The incoming boundary condition is employed in solving coupled-channel equations, which enables us to define the flux for complete fusion inside the Coulomb barrier. It is shown that complete fusion cross sections are significantly enhanced due to the couplings to the continuum states compared with the no-coupling case at energies below the Coulomb barrier, while they are hindered at above barrier energies.