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Infrared factorization of tree-level QCD amplitudes at the next-to-next-to-leading order and beyond

S. Catani·M. Grazzini
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Abstract

We study the infrared behaviour of tree-level QCD amplitudes and we derive infrared-factorization formulae that are valid at any perturbative order. We explicitly compute all the universal infrared factors that control the singularities in the various soft and/or collinear limits at O(as^2).

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S. Catani, M. Grazzini. 1999-08-31. Infrared factorization of tree-level QCD amplitudes at the next-to-next-to-leading order and beyond. https://doi.org/10.1016/s0550-3213(99)00778-6

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