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arXiv · 1208.0190

Complex Factorisation and Recursion for One-Loop Amplitudes

Sam D. Alston·David C. Dunbar·Warren B. Perkins
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Abstract

We consider the factorisation of one-loop amplitudes at complex kinematic points. By determining the terms that are absent for real kinematics, we can construct a recursive ansatz for the purely rational pieces of one-loop amplitudes in massless theories. We illustrate this method by verifying the Bern et.al. n-point ansatze for the single-minus one-loop amplitudes in Yang-Mills theory and by constructing the scalar contribution to the one-loop five graviton MHV scattering amplitude.

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Sam D. Alston, David C. Dunbar, Warren B. Perkins. 2012-08-01. Complex Factorisation and Recursion for One-Loop Amplitudes. https://doi.org/10.1103/physrevd.86.085022

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