Nucleon polarizabilities in virtual Compton scattering

We present calculations of the momentum dependence of generalized electric, magnetic, and spin-dependent polarizabilities of the proton in virtual Compton scattering in an effective Lagrangian model which includes the nucleon, pi, sigma, rho, and omega mesons, and baryon resonances with masses up to 1.7 GeV. The model describes simultaneously pion-nucleon scattering phase shifts, pion photoproduction multipoles, and Compton scattering cross sections. The unitarity within the channel space pi N+gamma N is achieved in the K-matrix approach. The different contributions to the generalized polarizabilities are studied.