Relativistic Impulse Approximation forp-Nucleus Elastic Scattering

First calculations based on an impulse-approximation Dirac optical potential are presented. All input parameters are constrained by other experimentally determined quantities. Excellent agreement with $T_p=500\mathrm{}$ MeV $p_{\mathrm{pol}}$+${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ and ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$ elastic scattering data is demonstrated. The differences between the relativistic and nonrelativistic results are explored in detail.