High-Energy Pion-Nucleus Scattering

Abstract

It is suggested that an inconsistency in the customary treatment of Pauli principle effects is responsible for the discrepancy between the experimentally observed scattering cross sections of high-energy pions on nuclei and the values calculated from two-body amplitudes in the impulse approximation. The effect considered, and briefly discussed within the framework of a $t$-matrix theory, is the inverse eclipse effect noted by Glauber. Results are stated for the optical potential and the effective cross section and numerical values are quoted for negative pions on ${\mathrm{C}}^{12}$.