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Related papers: Two-loop six gluon all plus helicity amplitude

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Two-loop four-gluon N=4 susy amplitudes are evaluated via cutting techniques as a testing ground for QCD. A conjecture for four-point amplitudes to all loop orders is described. We also present a new conjecture for the leading-color part of…

High Energy Physics - Phenomenology · Physics 2009-10-30 Z. Bern , J. Rozowsky , B. Yan

We compute the complete one-loop corrections to the simplest class of QCD gluon amplitudes, those with two color-adjacent opposite-helicity external particles. We present results for an arbitrary number of external legs. The computation…

High Energy Physics - Phenomenology · Physics 2009-11-11 Darren Forde , David A. Kosower

We present an expression for the QCD amplitude for a general hard scattering process with any number of soft gluon emissions, to one-loop accuracy. The amplitude is written in two different but equivalent ways: as a product of operators…

High Energy Physics - Phenomenology · Physics 2016-06-01 René Ángeles-Martínez , Jeffrey R. Forshaw , Michael H. Seymour

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 compute the three-loop helicity amplitudes for the scattering of four gluons in QCD. We employ projectors in the 't Hooft-Veltman scheme and construct the amplitudes from a minimal set of physical building blocks, which allows us to keep…

High Energy Physics - Phenomenology · Physics 2023-11-30 Fabrizio Caola , Amlan Chakraborty , Giulio Gambuti , Andreas von Manteuffel , Lorenzo Tancredi

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 compute the two-loop massless QCD corrections to the helicity amplitudes for the production of two electroweak gauge bosons in the gluon fusion channel, $gg \to V_1 V_2$, keeping the virtuality of the vector bosons $V_1$ and $V_2$…

High Energy Physics - Phenomenology · Physics 2015-09-14 Andreas von Manteuffel , Lorenzo Tancredi

We compute the leading colour contributions to five-gluon scattering at two loops in massless QCD. The integrands of all independent helicity amplitudes are evaluated using d-dimensional generalised unitarity cuts and finite field…

High Energy Physics - Phenomenology · Physics 2018-03-07 Simon Badger , Christian Brønnum-Hansen , Heribertus Bayu Hartanto , Tiziano Peraro

The ability to calculate analytic full-colour two-to-three two-loop helicity amplitudes in massless QCD has been a recent triumph of the field, driving phenomenology towards one percent precision. In this contribution, we focus on the…

High Energy Physics - Phenomenology · Physics 2023-10-31 Ryan Moodie

We combine the unitarity method with the six-dimensional helicity formalism of Cheung and O'Connell to construct loop-level scattering amplitudes. As a first example, we construct dimensionally regularized QCD one-loop four-point…

High Energy Physics - Theory · Physics 2015-03-17 Zvi Bern , John Joseph Carrasco , Tristan Dennen , Yu-tin Huang , Harald Ita

We calculate one loop scattering amplitudes for arbitrary number of positive helicity on-shell gluons and one off-shell gluon treated within the quasi-multi Regge kinematics. The result is fully gauge invariant and possesses the correct…

High Energy Physics - Phenomenology · Physics 2021-03-05 Etienne Blanco , Andreas van Hameren , Piotr Kotko , Krzysztof Kutak

We compute the polylogarithmic parts of the two-loop four and five-graviton amplitudes where the external helicities are positive and express these in a simple compact analytic form. We use these to extract the $\ln(\mu^2)$ terms from both…

High Energy Physics - Theory · Physics 2017-03-01 David C. Dunbar , Guy R. Jehu , Warren B. Perkins

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 combine the six-dimensional helicity formalism of Cheung and O'Connell with D-dimensional generalized unitarity to obtain a new formalism for computing one-loop amplitudes in dimensionally regularized QCD. With this procedure, we…

High Energy Physics - Phenomenology · Physics 2013-05-29 Scott Davies

This article brings together in a single place the different components of the six gluon one-loop amplitude

High Energy Physics - Phenomenology · Physics 2009-01-12 David C Dunbar

We calculate the two-loop QCD corrections to $gg \to ZZ$ involving a closed top-quark loop. We present a new method to systematically construct linear combinations of Feynman integrals with a convergent parametric representation, where we…

High Energy Physics - Phenomenology · Physics 2021-06-16 Bakul Agarwal , Stephen P. Jones , Andreas von Manteuffel

A general formalism for computing only the rational parts of oneloop QCD amplitudes is developed. Starting from the Feynman integral representation of the one-loop amplitude, we use tensor reduction and recursive relations to compute the…

High Energy Physics - Phenomenology · Physics 2009-11-11 Zhi-Guang Xiao , Gang Yang , Chuan-Jie Zhu

We present the leading-color two-loop QCD corrections for Higgs-boson production in association with two jets through gluon fusion in the heavy-top effective theory. We provide analytic expressions for the finite remainders of the helicity…

High Energy Physics - Phenomenology · Physics 2026-05-06 Giuseppe De Laurentis , Harald Ita , Viktor Kuschke , Michael Ruf , Vasily Sotnikov

We present the first numerical computation of two-loop amplitudes based on the unitarity method. As a proof of principle, we compute the four-gluon process. We discuss the new method, analyze its numerical properties and apply it to…

High Energy Physics - Phenomenology · Physics 2017-10-11 S. Abreu , F. Febres Cordero , H. Ita , M. Jaquier , B. Page , M. Zeng

We review recent progress in D-dimensional integrand reduction algorithms for two loop amplitudes and give examples of their application to non-planar maximal cuts of the five-point all-plus helicity amplitude in QCD.

High Energy Physics - Phenomenology · Physics 2014-07-14 Simon Badger , Hjalte Frellesvig , Yang Zhang