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One-Loop n-Point Gauge Theory Amplitudes, Unitarity and Collinear Limits

Z. Bern·L. Dixon·D. C. Dunbar·D. A. Kosower
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Abstract

We present a technique which utilizes unitarity and collinear limits to construct ansatze for one-loop amplitudes in gauge theory. As an example, we obtain the one-loop contribution to amplitudes for $n$ gluon scattering in $N=4$ supersymmetric Yang-Mills theory with the helicity configuration of the Parke-Taylor tree amplitudes. We prove that our $N=4$ ansatz is correct using general properties of the relevant one-loop $n$-point integrals. We also give the ``splitting amplitudes'' which govern the collinear behavior of one-loop helicity amplitudes in gauge theories.

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Z. Bern, L. Dixon, D. C. Dunbar, D. A. Kosower. 1994-03-16. One-Loop n-Point Gauge Theory Amplitudes, Unitarity and Collinear Limits. https://doi.org/10.1016/0550-3213(94)90179-1

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