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arXiv · 0912.1680

A simple formula for the infrared singular part of the integrand of one-loop QCD amplitudes

Mohammad Assadsolimani·Sebastian Becker·Stefan Weinzierl
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Abstract

We show that a well-known simple formula for the explicit infrared poles of one-loop QCD amplitudes has a corresponding simple counterpart in unintegrated form. The unintegrated formula approximates the integrand of one-loop QCD amplitudes in all soft and collinear singular regions. It thus defines a local counter-term for the infrared singularities and can be used as an ingredient for the numerical calculation of one-loop amplitudes.

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Mohammad Assadsolimani, Sebastian Becker, Stefan Weinzierl. 2009-12-09. A simple formula for the infrared singular part of the integrand of one-loop QCD amplitudes. https://doi.org/10.1103/physrevd.81.094002

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