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arXiv · 1611.04380

QCD amplitudes with 2 initial spacelike legs via generalised BCFW recursion

Andreas van Hameren·Krzysztof Kutak·Mirko Serino
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Abstract

We complete the generalisation of the BCFW recursion relation to the off-shell case, allowing for the computation of tree level scattering amplitudes for full High Energy Factorisation (HEF), i.e. with both incoming partons having a non-vanishing transverse momentum. We provide explicit results for color-ordered amplitudes with two off-shell legs in massless QCD up to 4 point, continuing the program begun in two previous papers. For the 4-fermion amplitudes, which are not BCFW-recursible, we perform a diagrammatic computation, so as to offer a complete set of expressions. We explicitly show and discuss some plots of the squared $2 \rightarrow 2$ matrix elements as functions of the differences in rapidity and azimuthal angle of the final state particles.

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Andreas van Hameren, Krzysztof Kutak, Mirko Serino. 2017-02-02. QCD amplitudes with 2 initial spacelike legs via generalised BCFW recursion. https://arxiv.org/abs/1611.04380

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