Delineating the polarized and unpolarized photon distributions of the   nucleon in eN collisions
  The production rates of lepton-photon and dimuon pairs at the HERA collider and the HERMES experiment are evaluated in the leading order equivalent photon approximation. It is shown that the production rates are sufficient to facilitate the extraction of the polarized and unpolarized equivalent photon distributions of the proton and neutron in the available kinematical regions. It is pointed out that these results indicate the possibility of additional, independent, tests concerning the unpolarized and polarized structure functions F_{1,2}^N and g_{1,2}^N, respectively, of the nucleon. 
M. Gl{\"}uck, C. Pisano, E. Reya, I. Schienbein (Dortmund U.)