One-Loop n-Point Gauge Theory Amplitudes, Unitarity and Collinear Limits
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In this paper, the authors presented a technique which utilizes unitarity and collinear limits to construct ansatze for one-loop amplitudes in gauge theory, and proved that their $N=4$ ansatz is correct using general properties of the relevant one-loops $n$-point integrals.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.read more
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References
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Journal ArticleDOI
One-loop n-gluon amplitudes with maximal helicity violation via collinear limits.
TL;DR: A conjecture is presented that the corresponding amplitudes where three or more gluon legs are replaced by photons vanish for [ital n][gt]4.
Book
The Ubiquitous photon: Helicity method for QED and QCD
Raymond Gastmans,T.T. Wu +1 more
TL;DR: In this article, the production of quarkonia has been studied using the Feynman diagrams and the Helicity states of single bremsstrahlung in QED and double bremsstrahlung in the QCD.
Journal ArticleDOI
Algebraic reduction of one-loop Feynman diagrams to scalar integrals. II
Robin G. Stuart,A. Góngora-T. +1 more
TL;DR: In this paper, it is shown how all one-loop integrals arising from Feynman diagrams in general gauge theory can be reduced to scalar integrals. But the scheme presented here successfully treats the case when the momenta are linear dependent.