Binding And Pauli Principle Corrections In Sub-Threshold Pion-Nucleus Scattering

In this investigation I develop a three-body model for the single scattering optical potential in which the nucleon binding and the Pauli principle are accounted for. A unitarity pole approximation is used for the nucleon-core interaction. Calculations are presented for the π−4He elastic scattering cross sections at energies below the inelastic threshold and for the real part of the π−4He scattering length by solving the three-body equations. Off-shell kinematics and the Pauli principle are carefully taken into account.