Exploring Nucleon-Nucleon correlations in ($e,e'NN$) reactions

Correlations in the nuclear wave-function beyond the mean-field or Hartree-Fock approximation are very important to describe basic properties of nuclear structure. Attempts are made to explore details of these correlations in exclusive nucleon knock-out by electron scattering experiments. Basic results of $(e,e'p)$ experiments are reviewed. The role of correlations in $(e,e'NN)$ experiments is discussed. Special attention is paid to a consistent description of the competing effects due to final state interaction, meson exchange current and isobar currents. Results are discussed for systematic studies of these features in nuclear matter as well as for specific examples for the finite nucleus $^{16}$O.