Meson Theory of the Dirac Impulse Approximation

A new formulation of the Dirac impulse approximation is discussed which connects the $p$-nucleus optical potential to a dynamical description of the relativistic $\mathrm{NN}$ amplitude. Use of pseudovector $\pi N$ coupling eliminates rapid energy dependence found in the original impulse approximation. First calculations demonstrate success for 181 MeV with no loss of effectiveness at 500 and 800 MeV.