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arXiv · 1110.2625

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

Norihisa Watanabe·Yuichiro Kiyo·Ken Sasaki
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Abstract

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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Norihisa Watanabe, Yuichiro Kiyo, Ken Sasaki. 2011-10-12. The polarized photon structure function $g_1^\gamma(x,Q^2)$ in massive parton model in NLO. https://doi.org/10.1016/j.physletb.2011.12.036

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