Heavy-ion fusion reactions at energies near and below the
Coulomb barrier have provided an interesting tool to
investigate nuclear structure. At these energies, the fusion
reaction takes place by quantum tunneling, and the effect of
the coupling of the relative motion between the colliding nuclei
to collective excitations is significantly amplified. This
results in the subbarrier enhancement of fusion cross sections
as compared to the fusion cross sections in the absence of the
coupling.
In this lecture, I will discuss how one can study the coupling
effect using the so called barrier distribution technique, that
is based on the coupled-channels approach to heavy-ion reactions.
I will also cover a few recent topics in the field, that include:
fusion reaction induced by neutron-rich nuclei, quasi-elastic
barrier distributions, the fusion potential anomaly, and fusion
reactions of massive systems.