0 50 50 05 v 1 2 M ay 2 00 5 A relativistic Glauber approach to polarization transfer in 4 He ( ~ e , e ′

Polarization-transfer components for He(~e, e~ p)H are computed within the relativistic multiplescattering Glauber approximation (RMSGA). The RMSGA framework adopts relativistic singleparticle wave functions and electron-nucleon couplings. The predictions with free and various parametrizations for the medium-modified electromagnetic form factors are compared to the world data. In conventional nuclear physics nuclei are described in terms of point-like protons and neutrons, interacting through the exchange of mesons. It has been a long-standing and unresolved issue whether the electromagnetic properties of bound nucleons differ from those of free nucleons. Exclusive A(~e, e~ p) measurements have been put forward as a tool to investigate the possible modifications attributed to the presence of a medium. In polarized electron free-proton scattering,the ratio of the electric (GE(Q 2 = −qqμ)) to the magnetic (GM(Q )) Sachs form factors, can be extracted from [1] P ′ x P ′ z = − GE(Q ) GM(Q) 2Mp Ee + Ee′ tan (