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arXiv · 1311.0304

High-energy QCD amplitudes at two loops and beyond

Vittorio Del Duca·Giulio Falcioni·Lorenzo Magnea·Leonardo Vernazza
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Abstract

Recent progress in our understanding of infrared singularities of multi-parton amplitudes has shown that the simplest form of Regge factorization for high-energy gauge-theory amplitudes fails starting at next-to-next-to-leading logarithmic accuracy. We provide a framework to organize the calculation of parton amplitudes at leading power in t/s, in terms of factorizing and non-factorizing contributions. This allows us to give explicit expressions for the leading Reggeization-breaking terms in two-loop and three-loop quark and gluon amplitudes in QCD. In particular, using only infrared information, we recover a known non-factorizing, non-logarithmic double-pole contribution at two-loops, and we compute the leading non-factorizing single-logarithmic contributions at three loops.

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Vittorio Del Duca, Giulio Falcioni, Lorenzo Magnea, Leonardo Vernazza. 2013-11-01. High-energy QCD amplitudes at two loops and beyond. https://doi.org/10.1016/j.physletb.2014.03.033

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