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arXiv · 2011.13946

Di-photon amplitudes in three-loop Quantum Chromodynamics

Fabrizio Caola·Andreas von Manteuffel·Lorenzo Tancredi
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Abstract

We consider the three-loop scattering amplitudes for the production of a pair of photons in quark-antiquark annihilation in Quantum Chromodynamics (QCD). We use suitably defined projectors to efficiently calculate all helicity amplitudes. We obtain relatively compact analytic results, that we write in terms of harmonic polylogarithms or, alternatively, multiple polylogarithms of up to depth three. This is the first calculation of a three-loop four-point scattering amplitude in full QCD.

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Fabrizio Caola, Andreas von Manteuffel, Lorenzo Tancredi. 2020-11-27. Di-photon amplitudes in three-loop Quantum Chromodynamics. https://doi.org/10.1103/physrevlett.126.112004

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