Determination of the Nuclear Symmetry Energy at 9.8 MeV. II. Optical-Model Analysis

In order to determine the nuclear symmetry energy at 10 MeV, an optical-model analysis is made of the elastic-scattering data resulting from the experiment described in Paper I, in which ${\mathrm{Sn}}^{112}$, ${\mathrm{Sn}}^{116}$, ${\mathrm{Sn}}^{120}$, and ${\mathrm{Sn}}^{124}$ targets were bombarded with 9.8-MeV protons. Several sets of geometrical parameters are held constant during the analysis, but none produce real potential-well depths which vary linearly with $\frac{\mathrm{}(N-Z)\mathrm{}}{A}$ over the isotopic range. The uncertainties inherent in the fitting procedure are fully investigated and an attempt is made to relate them to the errors in the experimental data.