  Photon distribution amplitudes up to twist four are calculated within the
nonlocal chiral quark model with a simple pole ansatz for momentum dependence
of the constituent quark mass. Calculations are performed using modified
electromagnetic vector current in order to satisfy Ward identities. Quark
condensate and magnetic susceptibility of the QCD vacuum entering definitions
of the distribution amplitudes are computed and compared with existing
phenomenological estimates. Both real and off-shell photons are considered and
relevant form factors are calculated. Our results are analytical up to the
numerical solution of certain algebraic equation.
