NNLO QCD corrections to $pp \to \gamma^* \gamma^*$ in the large $N_F$ limit

Charalampos Anastasiou; Julian Cancino; Federico Chavez; Claude Duhr; Achilleas Lazopoulos; Bernhard Mistlberger; Romain Mueller

doi:10.1007/jhep02(2015)182

arXiv · 1408.4546

NNLO QCD corrections to $pp \to \gamma^* \gamma^*$ in the large $N_F$ limit

Charalampos Anastasiou·Julian Cancino·Federico Chavez·Claude Duhr·Achilleas Lazopoulos·Bernhard Mistlberger·Romain Mueller

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Abstract

We compute the NNLO QCD corrections for the hadroproduction of a pair of off-shell photons in the limit of a large number of quark flavors. We perform a reduction of the two-loop amplitude to master integrals and calculate the latter analytically as a Laurent series in the dimensional regulator using modern integration methods. Real radiation corrections are evaluated numerically with a direct subtraction of infrared limits which we cast in a simple factorized form. The results presented here constitute a gauge invariant part of the full NNLO corrections but are not necessarily dominant. We view this calculation as a step towards a complete computation. Our partial corrections to the total cross-section are about $1\%-3\%$ and vary with the virtuality of the two off-shell photons.

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Charalampos Anastasiou, Julian Cancino, Federico Chavez, Claude Duhr, Achilleas Lazopoulos, Bernhard Mistlberger, Romain Mueller. 2014-08-20. NNLO QCD corrections to $pp \to \gamma^* \gamma^*$ in the large $N_F$ limit. https://doi.org/10.1007/jhep02(2015)182

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