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Related papers: Five-Parton Scattering in QCD at Two Loops

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In this work, we consider scattering amplitudes relevant for high-precision Large Hadron Collider (LHC) phenomenology. We analyse the general structure of amplitudes, and we review state-of-the-art methods for computing them. We discuss…

High Energy Physics - Phenomenology · Physics 2023-11-14 Piotr Bargiela

We present the universal two-loop splitting functions that describe the limits of two-loop $n$-point amplitudes of massless particles when two of the momenta are collinear. To derive the splitting amplitudes, we take the collinear limits of…

High Energy Physics - Phenomenology · Physics 2009-11-10 S. D. Badger , E. W. N. Glover

We compute the three-loop helicity amplitudes for $q\bar{q} \to gg$ and its crossed partonic channels, in massless QCD. Our analytical results provide a non-trivial check of the color quadrupole contribution to the infrared poles for…

High Energy Physics - Phenomenology · Physics 2023-01-04 Fabrizio Caola , Amlan Chakraborty , Giulio Gambuti , Andreas von Manteuffel , Lorenzo Tancredi

We compute the planar part of the two-loop five gluon amplitude with all helicities positive. To perform the calculation we develop a D-dimensional generalized unitarity procedure allowing us to reconstruct the amplitude by cutting into…

High Energy Physics - Phenomenology · Physics 2015-07-21 Simon Badger , Hjalte Frellesvig , Yang Zhang

We compute the full-color two-loop five-gluon amplitude for the all-plus helicity configuration. In order to achieve this, we calculate the required master integrals for all permutations of the external legs, in the physical scattering…

High Energy Physics - Phenomenology · Physics 2019-08-21 S. Badger , D. Chicherin , T. Gehrmann , G. Heinrich , J. M. Henn , T. Peraro , P. Wasser , Y. Zhang , S. Zoia

We review techniques for more efficient computation of perturbative scattering amplitudes in gauge theory, in particular tree and one-loop multi-parton amplitudes in QCD. We emphasize the advantages of (1) using color and helicity…

High Energy Physics - Phenomenology · Physics 2008-02-03 L. Dixon

Virtual two-loop corrections to scattering amplitudes are a key ingredient to precision physics at collider experiments. We compute the full set of planar master integrals relevant to five-point functions in massless QCD, and use these to…

High Energy Physics - Phenomenology · Physics 2016-04-18 T. Gehrmann , J. M. Henn , N. A. Lo Presti

We present the complete two-loop corrections in massless QCD for the production of two photons and a jet, taking into account all color structures. In particular, we analytically compute all two-loop helicity amplitudes for the…

High Energy Physics - Phenomenology · Physics 2022-01-05 Bakul Agarwal , Federico Buccioni , Andreas von Manteuffel , Lorenzo Tancredi

We calculate the complete set of two-loop leading-colour QCD helicity amplitudes for $\gamma \gamma j$-production at hadron colliders. Our results are presented in a compact, fully-analytical form.

High Energy Physics - Phenomenology · Physics 2021-08-25 Herschel A. Chawdhry , Michal Czakon , Alexander Mitov , Rene Poncelet

We compute the two-loop QCD helicity amplitudes for the production of a Higgs boson in association with a bottom-quark pair at a hadron collider. We take the approximations of leading colour and work in the five flavour scheme, where the…

High Energy Physics - Phenomenology · Physics 2021-11-24 Simon Badger , Heribertus Bayu Hartanto , Jakub Kryś , Simone Zoia

We complete the computation of two-loop helicity amplitudes required to obtain next-to-next-to-leading order QCD corrections for three-jet production at hadron colliders, including all contributions beyond the leading-color approximation.…

High Energy Physics - Phenomenology · Physics 2024-05-15 Giuseppe De Laurentis , Harald Ita , Vasily Sotnikov

We consider the three-loop scattering amplitudes for the production of a pair of photons in quark-antiquark annihilation in Quantum Chromodynamics (QCD). We use suitably defined projectors to efficiently calculate all helicity amplitudes.…

High Energy Physics - Phenomenology · Physics 2021-03-24 Fabrizio Caola , Andreas von Manteuffel , Lorenzo Tancredi

We discuss the calculation of two-loop helicity amplitudes for quark-quark scattering in QCD and four-gluino scattering in N=1 supersymmetric Yang-Mills theory. We study the dependence of the results on different variants of dimensional…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. De Freitas , Z. Bern

We present recent advancements in the computation of three-loop four-particle helicity amplitudes in full-color massless QCD. In this contribution, we focus on the $gg \to \gamma\gamma$ process. We show how to obtain compact analytic…

High Energy Physics - Phenomenology · Physics 2024-10-04 Piotr Bargiela

We study QCD helicity amplitudes with an arbitrary number of (massive) quarks, keeping unobserved (loop) particles in fixed integer $D_s$ dimensions. We find a suitable embedding of external four-dimensional fermion states into higher…

High Energy Physics - Phenomenology · Physics 2018-04-16 F. R. Anger , V. Sotnikov

We review recent progress on the calculation of scattering amplitudes in the high-energy limit. We start by illustrating the shockwave formalism, which allows one to calculate amplitudes as iterated solutions of rapidity evolution…

High Energy Physics - Phenomenology · Physics 2021-11-10 Leonardo Vernazza , Giulio Falcioni , Einan Gardi , Niamh Maher , Calum Milloy

We present the two-loop helicity amplitudes for the scattering of two gluons into two gluons in QCD, which are relevant for next-to-next-to-leading order corrections to jet production at hadron colliders. We give the results in the `t…

High Energy Physics - Phenomenology · Physics 2010-04-06 Zvi Bern , Abilio De Freitas , Lance Dixon

We present novel techniques for the computation of three-loop four-parton scattering amplitudes in full color, non-planar gauge theories. We elaborate on how the analytic results for these amplitudes can be used to confirm the conjectured…

High Energy Physics - Phenomenology · Physics 2022-08-18 Amlan Chakraborty , Giulio Gambuti

We compute all helicity amplitudes for four-particle scattering in massless QCD with $n_f$ fermion flavours to next-to-next-to-leading order (NNLO) in perturbation theory. In particular, we consider all possible configurations of external…

High Energy Physics - Phenomenology · Physics 2020-01-23 Taushif Ahmed , Johannes Henn , Bernhard Mistlberger

I discuss the status of the computation of the two-loop QCD corrections to top-quark pair production associated with a jet at hadron colliders. This amplitude is a missing ingredient for next-to-next-to-leading order (NNLO) QCD predictions.…

High Energy Physics - Phenomenology · Physics 2024-11-19 Colomba Brancaccio