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arXiv · 1004.3653

Calculation of the quark and gluon form factors to three loops in QCD

T. Gehrmann·E. W. N. Glover·T. Huber·N. Ikizlerli·C. Studerus
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Abstract

We describe the calculation of the three-loop QCD corrections to quark and gluon form factors. The relevant three-loop Feynman diagrams are evaluated and the resulting three-loop Feynman integrals are reduced to a small set of known master integrals by using integration-by-parts relations. Our calculation confirms the recent results by Baikov et al.\ for the three-loop form factors. In addition, we derive the subleading ${\cal O}(\epsilon)$ terms for the fermion-loop type contributions to the three-loop form factors which are required for the extraction of the fermionic contributions to the four-loop quark and gluon collinear anomalous dimensions. The finite parts of the form factors are used to determine the hard matching coefficients for the Drell-Yan process and inclusive Higgs-production in soft-collinear effective theory.

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T. Gehrmann, E. W. N. Glover, T. Huber, N. Ikizlerli, C. Studerus. 2010-04-21. Calculation of the quark and gluon form factors to three loops in QCD. https://doi.org/10.1007/jhep06(2010)094

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