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arXiv · 1306.5509

The real photon structure functions 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 real photon structure functions $W_{TT} $, $W_{LT}$, $W_{TT}^{a} $ and $W_{TT}^\tau$ in the massive parton model. We employ a technique based on the Cutkosky rules and the reduction of Feynman integrals to master integrals. We show that a positivity constraint, which is derived from the Cauchy-Schwarz inequality, is satisfied among the unpolarized and polarized structure functions $W_{TT}$, $W_{TT}^a$ and $W_{TT}^\tau$ calculated up to the next-to-leading order in QCD.

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Norihisa Watanabe, Yuichiro Kiyo, Ken Sasaki. 2013-06-24. The real photon structure functions in massive parton model in NLO. https://doi.org/10.1103/physrevd.88.034022

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