Photo- and Electro-excitation of Bound Neutrons and Protons

Data for pion photo-productions off the neutron (gamma n -> pi N) have been primarily extracted from deuteron-target data (gamma d -> pi NN) by applying kinematical cuts thereby isolating the quasi-free samples. We critically examine if the neutron-target data obtained through this conventional procedure can be contaminated by final state interactions (FSI) and/or the kinematical cuts. The analysis is conducted with a theoretical model for gamma d -> pi NN that takes account of the impulse mechanisms supplemented by the NN and pi N rescattering mechanisms. We show that the FSI effects still visibly remain in the extracted. gamma 'n' -> pi N unpolarized cross sections and polarization asymmetries E even after the kinematical cuts are applied. We also find the FSI effects on gamma 'n' -> pi(0)n can be somewhat different from those on gamma 'p'-> pi(0) p.