Double polarization observables in virtual Compton scattering

The polarized p(e, e′p)γ reaction is studied below the pion production threshold. Calculations within an effective Lagrangian formalism for the virtual Compton scattering double polarization observables are done for kinematics accessible at MAMI, MIT-Bates and TJNAF. A model independent interpretation of the nucleon structure effect is given by expressing these double polarization observables in terms of the generalized polarizabilities introduced by Guichon et al.