  We employ the non-perturbative time-dependent basis function (tBF) approach
to investigate in detail the sub-Coulomb barrier scattering of the deuteron
projectile on the $^{208}$Pb target. Specifically, we treat the target as a
quiescent source of a strong external Coulomb field that induces higher-order
effects in electric-dipole excitations of the deuteron projectile including the
population of states not accessible through direct electric-dipole transitions
from the ground state of the deuteron. We calculate the electric-dipole
polarizability of the deuteron and elastic scattering observables for
comparison with experimental data. With no adjustable parameters, the tBF
approach provides good agreement with experimentally available differential
cross-section ratios. The dependence of these measured quantities on
nucleon-nucleon interactions is investigated. The effects of the polarization
potential on the scattering observables are also presented in this work. We
also investigate the detailed scattering dynamics and identify characteristics
of coherent and incoherent processes.
