Effects of Nucleon Charge Exchange on the (π, πN) Puzzle

Charge-exchange interactions of the nucleons within the nucleus are shown to account for the observed differences in the ratios of neutron-knockout cross sections for ${\pi }^{\pm }$ from the impulse-approximation predictions. Also, the energy dependence of the knockout cross sections is obtained from the measured total pion reaction cross sections with a simple model for the threshold behavior.