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arXiv · 1812.04053

Positive helicity Einstein-Yang-Mills amplitudes from the Double Copy

Josua Faller·Jan Plefka
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Abstract

All positive helicity four-point gluon-graviton amplitudes in Einstein-Yang-Mills theory coupled to a dilaton and axion field are computed at the leading one-loop order using colour-kinematics duality. In particular, all relevant contributions in the gravitational and gauge coupling are established. This extends a previous generalized unitarity based computation beyond the leading terms in the gravitational coupling $\kappa$. The resulting purely rational expressions take very compact forms. The previously seen vanishing of the single-graviton-three-gluon amplitude at leading order in $\kappa$ is seen to be lifted at order $\kappa^{3}$.

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Josua Faller, Jan Plefka. 2018-12-10. Positive helicity Einstein-Yang-Mills amplitudes from the Double Copy. https://doi.org/10.1103/physrevd.99.046008

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