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 method. 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 leading-color two-loop 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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Abreu, S., Febres Cordero, F., Ita, H. et al. Planar two-loop five-parton amplitudes from numerical unitarity. J. High Energ. Phys. 2018, 116 (2018). https://doi.org/10.1007/JHEP11(2018)116
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DOI: https://doi.org/10.1007/JHEP11(2018)116