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arXiv · 2201.04075

Two-loop leading colour helicity amplitudes for $W^\pmγ+j$ production at the LHC

Simon Badger·Heribertus Bayu Hartanto·Jakub Kryś·Simone Zoia
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Abstract

We present the two-loop leading colour QCD helicity amplitudes for the process $pp\to W(\to lν)γ+j$. We implement a complete reduction of the amplitudes, including the leptonic decay of the $W$-boson, using finite field arithmetic, and extract the analytic finite remainders using a recently identified basis of special functions. Simplified analytic expressions are obtained after considering permutations of a rational kinematic parametrisation and multivariate partial fractioning. We demonstrate efficient numerical evaluation of the two-loop colour and helicity summed finite remainders for physical kinematics, and hence the suitability for phenomenological applications.

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Simon Badger, Heribertus Bayu Hartanto, Jakub Kryś, Simone Zoia. 2022-01-11. Two-loop leading colour helicity amplitudes for $W^\pmγ+j$ production at the LHC. https://doi.org/10.1007/jhep05(2022)035

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