Elastic Scattering ofHe3Ions at Intermediate Energies

The elastic scattering of ${\mathrm{He}}^3$ ions has been studied at 37.7 MeV from ${\mathrm{Ca}}^{40}$, ${\mathrm{Fe}}^{56}$, and ${\mathrm{Ni}}^{58}$ and at 43.7 MeV from ${\mathrm{Ni}}^{58}$, ${\mathrm{Y}}^{89}$, and ${\mathrm{Zr}}^{90}$. A theoretical analysis has been carried out in terms of the optical model. Both discrete and continuous ambiguities in the optical-model parameters appear, and are discussed in some detail. An average potential has been selected which adequately accounts for our data as well as some reaction data of others. In the case of ${\mathrm{Ca}}^{40}$ and ${\mathrm{Ni}}^{58}$, the energy dependence of the real and imaginary well depths has been investigated using a standard geometry. Similarly, the $A$ dependence of the well depths has been examined.