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arXiv · 0709.4044

NLO QCD corrections to the production of t-tbar-Z in gluon fusion

Achilleas Lazopoulos·Kirill Melnikov·Frank Petriello
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Abstract

We compute the O(alpha_s) QCD corrections to the partonic process gg -> t-tbar-Z at the LHC. This partonic channel is the dominant component of the scattering process pp -> t-tbar-Z, which will be important for measuring the t-tbar-Z electroweak couplings. The O(alpha_s) corrections increase the total cross section by up to 75% for reasonable choices of the renormalization and factorization scales. Inclusion of these contributions descreases the residual scale dependence of the cross section coming from uncalculated higher order terms to +-5%.

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Achilleas Lazopoulos, Kirill Melnikov, Frank Petriello. 2007-09-25. NLO QCD corrections to the production of t-tbar-Z in gluon fusion. https://doi.org/10.1103/physrevd.77.034021

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