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Related papers: Local integrands for two-loop QCD amplitudes

200 papers

We shall interpret the null hexagonal Wilson loop (or, equivalently, six gluon scattering amplitude) in 4D ${\cal N}=4$ Super Yang-Mills, or, precisely, an integral representation of its matrix part, via an ADHM-like instanton construction.…

High Energy Physics - Theory · Physics 2021-11-03 Davide Fioravanti , Hasmik Poghosyan , Rubik Poghossian

We discuss recent progress in multi-loop integrand reduction methods. Motivated by the possibility of an automated construction of multi-loop amplitudes via generalized unitarity cuts we describe a procedure to obtain a general…

High Energy Physics - Phenomenology · Physics 2015-06-17 Simon Badger , Hjalte Frellesvig , Yang Zhang

We compute the symbol of the two-loop five-point scattering amplitude in $\mathcal{N}$ = 4 super-Yang-Mills theory, including its full color dependence. This requires constructing the symbol of all two-loop five-point nonplanar massless…

High Energy Physics - Theory · Physics 2019-04-03 Samuel Abreu , Lance J. Dixon , Enrico Herrmann , Ben Page , Mao Zeng

We compute the two-loop QCD helicity amplitudes for the process e^+e^- --> q bar{q} g. The amplitudes are extracted in a scheme-independent manner from the coefficients appearing in the general tensorial structure for this process. The…

High Energy Physics - Phenomenology · Physics 2010-04-06 L. W. Garland , T. Gehrmann , E. W. N. Glover , A. Koukoutsakis , E. Remiddi

We explore the relation between resummation and explicit multi-loop calculations for QCD hard-scattering amplitudes. We describe how the factorization properties of amplitudes lead to the exponentiation of double and single poles at each…

High Energy Physics - Phenomenology · Physics 2014-11-17 George Sterman , Maria E. Tejeda-Yeomans

The calculation of scattering amplitudes in Yang-Mills theory at loop level is important for the analysis of background processes at particle colliders as well as our understanding of perturbation theory at the quantum level. We present…

High Energy Physics - Theory · Physics 2013-05-30 Rutger H. Boels , Reinke Sven Isermann

Loop amplitudes are conveniently expressed in terms of master integrals whose coefficients carry the process dependent information. Similarly before integration, the loop integrands may be expressed as a linear combination of propagator…

High Energy Physics - Theory · Physics 2016-12-28 Harald Ita

We present an integral representation for the parity-even part of the two-loop six-point planar NMHV amplitude in terms of Feynman integrals which have simple transformation properties under the dual conformal symmetry. We probe the dual…

High Energy Physics - Theory · Physics 2011-03-22 D. A. Kosower , R. Roiban , C. Vergu

We study a five-leg scattering amplitude on the special Coulomb branch of planar N=4 super Yang-Mills theory. We reach this point of the moduli space of scalar vacuum expectation values by considering six-dimensional N=(1,1) super…

High Energy Physics - Theory · Physics 2025-10-21 A. V. Belitsky , L. V. Bork , R. N. Lee , A. I. Onishchenko , V. A. Smirnov

We obtain local numerators satisfying the BCJ color-kinematics duality at one loop for super-Yang-Mills theory in ten dimensions. This is done explicitly for six points via the field-theory limit of the genus-one open superstring…

High Energy Physics - Theory · Physics 2021-07-28 Elliot Bridges , Carlos R. Mafra

We use on-shell recursion relations to determine the one-loop QCD scattering amplitudes with a massless external quark pair and an arbitrary number (n-2) of positive-helicity gluons. These amplitudes are the last of the unknown infrared-…

High Energy Physics - Phenomenology · Physics 2010-11-15 Zvi Bern , Lance J. Dixon , David A. Kosower

We derive the structure of three-loop anomalous dimensions governing infrared singularities of QCD amplitudes with one massive and an arbitrary number of massless external partons. The contributions of tripole and quadrupole correlations…

High Energy Physics - Phenomenology · Physics 2022-12-09 Ze Long Liu , Nicolas Schalch

We study a two-parameter family of Wilson loop operators in N=4 supersymmetric Yang-Mills theory which interpolates smoothly between the 1/2 BPS line or circle and a pair of antiparallel lines. These observables capture a natural…

High Energy Physics - Theory · Physics 2015-05-28 Nadav Drukker , Valentina Forini

We propose a procedure to determine the moduli-space integrands of loop-level superstring amplitudes for massless external states in terms of the field theory limit. We focus on the type II superstring. The procedure is to: (i) take a…

High Energy Physics - Theory · Physics 2021-11-19 Yvonne Geyer , Ricardo Monteiro , Ricardo Stark-Muchão

Using the double-copy construction of Yang-Mills-Einstein theories formulated in our earlier work, we obtain compact presentations for single-trace Yang-Mills-Einstein tree amplitudes with up to five external gravitons and an arbitrary…

High Energy Physics - Theory · Physics 2017-08-25 Marco Chiodaroli , Murat Gunaydin , Henrik Johansson , Radu Roiban

In this thesis, we study the all same helicity loop amplitudes in self-dual Yang-Mills and self-dual gravity. These amplitudes have long been conjectured to be interpreted as an anomaly and are recently linked to the UV divergence of…

High Energy Physics - Theory · Physics 2023-10-24 Pratik Chattopadhyay

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 the two-loop pure gauge contribution to the gluon-gluon scattering amplitude with maximal helicity violation. Our construction of the amplitude does not rely directly on Feynman diagrams, but instead uses its analytic properties…

High Energy Physics - Phenomenology · Physics 2011-06-27 Z. Bern , L. Dixon , D. A. Kosower

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 advance the exploration of cluster-algebraic patterns in the building blocks of scattering amplitudes in $\mathcal{N}=4$ super Yang-Mills theory. In particular we conjecture that, given a maximal cut of a loop amplitude, Landau…

High Energy Physics - Theory · Physics 2020-05-15 Ömer Gürdoğan , Matteo Parisi