Meson-exchange currents effects in nucleon photoemission

The role of meson-exchange currents in (γ, p) and (γ, n) reactions at intermediate energies is investigated in the frame of a direct knockout model where the photon interacts with a pair of correlated nucleons. Realistic short-range correlations and final-state interactions are included in the calculations. Direct and exchange terms are considered. The results for 16O(γ, p) and 16O(γ, n) indicate that the two-body seagull current significantly affects the cross sections. In both cases the size and the shape of the experimental angular distributions are fairly well reproduced.