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arXiv · 2211.06465

Revisiting the double-soft asymptotics of one-loop amplitudes in massless QCD

Michał Czakon·Felix Eschment·Tom Schellenberger
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Abstract

We evaluate the one-loop soft current for the emission of two soft gluons or a soft quark-anti-quark pair in massless Quantum Chromodynamics. The results are exact in dimensional regularisation up to a single Feynman integral. Two terms of the Taylor series of the latter integral as a function of $\epsilon \equiv (4-d)/2$ with $d$ the dimension of spacetime are available from a recent calculation of one-loop triple-collinear splitting functions. Our formulae are necessary for the construction of a subtraction scheme for the evaluation of next-to-next-to-next-to-leading order cross sections in massless QCD.

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Michał Czakon, Felix Eschment, Tom Schellenberger. 2022-11-11. Revisiting the double-soft asymptotics of one-loop amplitudes in massless QCD. https://doi.org/10.1007/jhep04(2023)065

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