Abstract
A 3-body model of deuteron-nucleus scattering in which the neutron and proton of the deuteron interact with the nucleus through their respective optical potentials is solved approximately to yield the elastic channel wave-function and the projection of the break-up channel wavefunction into the region of configuration space where the neutron and proton are inside the range of their mutual interaction. The theory is applied to a description of the elastic scattering of deuterons from medium mass nuclei in the energy region 10-35 MeV. By comparison with a calculation which does not include break-up contributions explicitly, we show that this correction produces systematic improvements in the fit to experiment. Our results suggest that a more exact 3-body treatment would not significantly alter our conclusions. An exclusion principle correction to the 3-body Hamiltonian is estimated in a nuclear matter approximation, and thus shown to correspond roughly to a reduction in depth of the deuteron-nucleus optical potential. The result of including this correction in our calculation, though distinct from 3-body effects, is a further improvement in the agreement with experiment. An important result of the 3-body treatment is that the elastic wave-function does not differ significantly in the nuclear interior from the wavefunction generated phenomenologically. These are the functions which would normally be used in DWBA stripping calculations. Our model, however, predicts the elastic plus break-up wavefunction as appropriate for this purpose, and this function does differ from those above particularly in the surface and asymptotic regions.