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arXiv · 1809.09067

Planar Two-Loop Five-Parton Amplitudes from Numerical Unitarity

S. Abreu·F. Febres Cordero·H. Ita·B. Page·V. Sotnikov
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Abstract

We compute a complete set of independent leading-color two-loop five-parton amplitudes in QCD. These constitute a fundamental ingredient for the next-to-next-to-leading order QCD corrections to three-jet production at hadron colliders. We show how to consistently consider helicity amplitudes with external fermions in dimensional regularization, allowing the application of a numerical variant of the unitarity approach. Amplitudes are computed by exploiting a decomposition of the integrand into master and surface terms that is independent of the parton type. Master integral coefficients are numerically computed in either finite-field or floating-point arithmetic and combined with known analytic master integrals. We recompute two-loop leading-color four-parton amplitudes as a check of our implementation. Results are presented for all independent four- and five-parton processes including contributions with massless closed fermion loops.

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S. Abreu, F. Febres Cordero, H. Ita, B. Page, V. Sotnikov. 2018-09-24. Planar Two-Loop Five-Parton Amplitudes from Numerical Unitarity. https://doi.org/10.1007/jhep11(2018)116

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