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Next-to-next-to-leading order ${\cal O}(α^2α_s^2)$ results for top quark pair production in photon--photon collisions: The one-loop squared contributions

J. G. Korner·Z. Merebashvili·M. Rogal
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Abstract

We calculate the one-loop squared contributions to the next-to-next-to-leading order ${\cal O}(α^2α_s^2)$ radiative QCD corrections for the production of heavy quark pairs in the collisions of unpolarized on--shell photons. In particular, we present analytical results for the squared matrix elements that correspond to the product of the one--loop amplitudes. All results of the perturbative calculation are given in the dimensional regularization scheme. These results represent the Abelian part of the corresponding gluon--induced next-to-next-to-leading order cross section for heavy quark pair hadroproduction.

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J. G. Korner, Z. Merebashvili, M. Rogal. 2006-11-04. Next-to-next-to-leading order ${\cal O}(α^2α_s^2)$ results for top quark pair production in photon--photon collisions: The one-loop squared contributions. https://doi.org/10.1103/physrevd.74.094006

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