  Various corrections to the eikonal approximations are studied for two- and
three-body nuclear collisions with the goal to extend the range of validity of
this approximation to beam energies of 10 MeV/nucleon. Wallace's correction
does not improve much the elastic-scattering cross sections obtained at the
usual eikonal approximation. On the contrary, a semiclassical approximation
that substitutes the impact parameter by a complex distance of closest approach
computed with the projectile-target optical potential efficiently corrects the
eikonal approximation. This opens the possibility to analyze data measured down
to 10 MeV/nucleon within eikonal-like reaction models.
