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arXiv · 0809.3980

Heavy quark pair production in gluon fusion at next-to-next-to-leading ${\cal O}(α_s^4)$ order: One-loop squared contributions

B. Kniehl·J. G. Körner·Z. Merebashvili·M. Rogal
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Abstract

We calculate the next-to-next-to-leading order ${\cal O}(α_s^4)$ one-loop squared corrections to the production of heavy-quark pairs in the gluon-gluon fusion process. Together with the previously derived results on the $q \bar{q}$ production channel the results of this paper complete the calculation of the one-loop squared contributions of the next-to-next-to-leading order ${\cal O}(α_s^4)$ radiative QCD corrections to the hadroproduction of heavy flavors. Our results, with the full mass dependence retained, are presented in a closed and very compact form, in dimensional regularization.

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B. Kniehl, J. G. Körner, Z. Merebashvili, M. Rogal. 2008-11-19. Heavy quark pair production in gluon fusion at next-to-next-to-leading ${\cal O}(α_s^4)$ order: One-loop squared contributions. https://doi.org/10.1103/physrevd.78.094013

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