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The polarized photon structure function $g_1^gamma(x,Q^2)$ in massive parton model in NLO

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 نشر من قبل Norihisa Watanabe
 تاريخ النشر 2011
  مجال البحث
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We investigate the one-gluon-exchange ($alpha alpha_s$) corrections to the polarized real photon structure function $g_1^gamma(x,Q^2)$ 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 $g_1^gamma$ is satisfied up to the NLO.

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