Deuteron Optical-Model Analysis in the Range of 11 to 27 MeV

Deuteron elastic scattering angular distributions are analyzed using a simple optical model without spin-orbit potentials. Discrete valleys in the parameter space of the model are found to give a very good description of the data. Two of these regions are used to analyze 52 angular distributions measured for target nuclei with $Z\ge 12$ and deuteron energies in the range of 11 to 27 MeV, with particular emphasis on data at energies of 11.8, 15, and 21.6 MeV. In order to determine the trends of the optical-model parameters as a function of mass number and energy, four different sets of geometrical parameters are used, and only the well depths, real and imaginary, are varied to obtain a best fit to the experimental data. The real well depths show a smooth linear increase as a function of the Coulomb parameter $\frac{Z}{A^{\frac{1}{3}}}$ and a smooth linear decrease as a function of energy. The imaginary well depths show fairly large fluctuations from element to element but no systematic trend as a function of mass number. For all four sets of parameters, the imaginary well depth decreases rapidly for bombarding energies from 11 to 14 MeV and then increases slowly for energies from 15 to 27 MeV.