The polarized photon structure function g1γ(x,Q2) in massive parton model in NLO

We investigate the one-gluon-exchange (ααs) corrections to the polarized real photon structure function g1γ(x,Q2) in the massive parton model. We employ a technique based on the Cutkosky rules and the reduction of Feynman integrals to master integrals. The NLO contribution is noticeable at large x and does not vanish at the threshold of the massive quark pair production due to the Coulomb singularity. It is found that the first moment sum rule of g1γ is satisfied up to the NLO.