MESON-EXCHANGE CURRENT EFFECTS IN INELASTIC ELECTRON-SCATTERING FROM POLARIZED NUCLEI

The effects of meson-exchange currents in the inelastic electron scattering from polarized nuclei to defined excited levels are investigated. The study has been carried out for five stable doubly closed-shell +/-1 nucleon nuclei: B-11, C-13, N-15, O-17 and K-39. All of them are described by means of the extreme shell model based on a Woods-Saxon type potential. Different transitions and target polarizations have been considered. A number of situations for which the observation of such effects is expected to be possible are discussed. It has been found that the presence of electric multipoles, forbidden in the elastic-scattering case, increases notably the effect of meson-exchange currents and enhances the feasibility of the experimental separation of the pieces of the cross section. Good situations to identify the meson-exchange currents are found both with polarized and unpolarized electron beam, their signal being in many cases much larger than in elastic scattering.