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arXiv · hep-ph/0210130

Multi-loop Amplitudes and Resummation

George Sterman·Maria E. Tejeda-Yeomans
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Abstract

We explore the relation between resummation and explicit multi-loop calculations for QCD hard-scattering amplitudes. We describe how the factorization properties of amplitudes lead to the exponentiation of double and single poles at each order of perturbation theory. For these amplitudes, previously-observed relations between single and double poles in different 2 to 2 processes can now be interpreted in terms of universal functions associated with external partons and process-dependent anomalous dimensions that describe coherent soft radiation. Catani's proposal for multiple poles in dimensionally-continued amplitudes emerges naturally.

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George Sterman, Maria E. Tejeda-Yeomans. 2005-04-06. Multi-loop Amplitudes and Resummation. https://doi.org/10.1016/s0370-2693(02)03100-3

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