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arXiv · 1411.1669

On the Subleading-Soft Behaviour of QCD Amplitudes

Hui Luo·Pierpaolo Mastrolia·William J. Torres Bobadilla
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Abstract

We elaborate on the radiative behaviour of tree-level scattering amplitudes in the soft regime. We show that the sub-leading soft term in single-gluon emission of quark-gluon amplitudes in QCD is controlled by differential operators, whose universal form can be derived from both on-shell recursion relation and gauge invariance, as it was shown to hold for graviton- and gluon-scattering.

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Hui Luo, Pierpaolo Mastrolia, William J. Torres Bobadilla. 2014-11-06. On the Subleading-Soft Behaviour of QCD Amplitudes. https://doi.org/10.1103/physrevd.91.065018

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