  The study of two body deuteron photo-disintegration is ideal for
investigating the transition region from meson exchange to the Quantum Chromo
Dynamics (QCD) regime because of its simplicity and amenability to calculation.
  In the past years, the theoretical efforts have been focused in two different
directions: extending at higher energies the models based on meson exchange,
and improving the models inspired by QCD principles to extrapolate their
predictions at lower energies, in order to find out the approach that best
describes the experimental data and in which energy region the transition
between the two descriptions takes place.
