Two-loop QCD helicity amplitudes for $g\,g \to Z\,g$ and $g\,g \to Z\,γ$

Thomas Gehrmann; Lorenzo Tancredi; Erich Weihs

doi:10.1007/jhep04(2013)101

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arXiv · 1302.2630

Two-loop QCD helicity amplitudes for $g\,g \to Z\,g$ and $g\,g \to Z\,γ$

Thomas Gehrmann·Lorenzo Tancredi·Erich Weihs

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Abstract

We compute the helicity amplitudes for the processes $gg\to Zg$ and $gg\to Zγ$ to two loops in massless QCD. The perturbative expansion of these processes starts only at the one-loop level, such that our results are a crucial ingredient to the NLO corrections to $Zγ$ and $Z+$jet production through gluon fusion.

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Thomas Gehrmann, Lorenzo Tancredi, Erich Weihs. 2023-08-18. Two-loop QCD helicity amplitudes for $g\,g \to Z\,g$ and $g\,g \to Z\,γ$. https://doi.org/10.1007/jhep04(2013)101

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