Quasi-free (e,e'N) reactions on polarized target

The quasi-free nucleon knockout by the electron is studied in the general case of both polarized beams and polarized targets. The coincidence cross section involves nine structure functions which give detailed information on the nuclear current operator. However, their measurement requires out-of-plane experiments. Results on 7Li and 39K obtained within the nonrelativistic DWIA framework indicate that some structure functions, very sensitive to final state interactions, are probably too small to be separated. On the other side, cross sections, asymmetries and electron polarization ratios in coplanar kinematics have measurable size. They add complementary information to the unpolarized quasi-free nucleon knockout because of their sensitivity to spin degrees of freedom which are averaged out without target polarization. In the particular case of a nucleon ejected along the direction of the momentum transfer from a target with spin oriented in the same direction (superparallel kinematics) only three structure functions survive and can be simply separated