Nucleon-nucleon correlations and two-nucleon currents in exclusive (e,e′NN) reactions -: art. no. 064603

The contributions of short-range nucleon-nucleon (NN) correlations, meson exchange current (MEC) terms, and the influence of Delta isobar excitations (isobaric currents) on exclusive two-nucleon knockout reactions induced by electron scattering are investigated. The nuclear structure functions are evaluated for nuclear matter. Realistic NN interactions derived in the framework of a one-boson-exchange model are employed to evaluate the effects of correlations and MEC in a consistent way. The correlations are determined by solving the Bethe-Goldstone equation. This yields significant contributions to the structure functions W-L and W-T of the (e,e' pn) and (e,e' pp) reactions. These contributions compete with MEC corrections originating from the pi and rho exchange terms of the same interaction. Special attention is paid to the so-called "superparallel" kinematics at momentum transfers which can be measured, e.g., at MAMI in Mainz.