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Related papers: MHV One-Loop Amplitudes in Yang-Mills from General…

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A c++ implementation of the D_s-dimensional unitarity cut algorithm for the numerical evaluation of the virtual contribution to NLO QCD amplitudes is presented. The current version includes an arbitrary number of external gluons with…

High Energy Physics - Phenomenology · Physics 2008-12-17 A. Lazopoulos

We study four point planar loop amplitudes at an arbitrary point in the Coulomb branch of $\mathcal{N}=4$ super-Yang-Mills theory. We study two particle unitary cuts up to four loop order. We explicitly verify that bubble and triangle…

High Energy Physics - Theory · Physics 2024-05-01 Md. Abhishek , Subramanya Hegde , Dileep P. Jatkar , Arnab Priya Saha , Amit Suthar

One-loop scattering amplitudes in N=4 super Yang-Mills (SYM) theories are analyzed in the paradigm of maximal helicity violating Feynman diagrams. There are very limited number of loop integrals to be evaluated. For a process with n…

High Energy Physics - Theory · Physics 2010-04-05 Mingxing Luo , Congkao Wen

We compute one-loop amplitudes in six-dimensional Yang-Mills theory with half-maximal supersymmetry from first principles: imposing gauge invariance and locality on an ansatz made from string-theory inspired kinematic building blocks yields…

High Energy Physics - Theory · Physics 2017-09-13 Marcus Berg , Igor Buchberger , Oliver Schlotterer

The unitarity method for calculating one-loop amplitudes provides algorithms of polynomial complexity. This is primarily beneficial for the computation of multi-leg one loop amplitudes and it is therefore of great interest to develop a…

High Energy Physics - Phenomenology · Physics 2009-04-14 R. Keith Ellis , Walter T. Giele , Zoltan Kunszt

By exploiting relations between gravity and gauge theories, we present two infinite sequences of one-loop n-graviton scattering amplitudes: the `maximally helicity-violating' amplitudes in N=8 supergravity, and the `all-plus' helicity…

High Energy Physics - Theory · Physics 2010-11-15 Z. Bern , L. Dixon , M. Perelstein , J. S. Rozowsky

Recent Developments in computing very specific helicity amplitudes in two loop QCD are presented. The techniques focus upon the singular structure of the amplitude rather than on a diagramatic and integration approach

High Energy Physics - Phenomenology · Physics 2017-12-15 David C. Dunbar , John H Godwin , Guy R. Jehu , Warren B. Perkins

In this paper we give all the details of the calculation that we presented in our previous paper ArXiv:0908.0387 where the infrared structure of the MHV gluon amplitudes in the planar limit for ${\cal N}=4$ super Yang-Mills theory was…

High Energy Physics - Theory · Physics 2010-06-29 L. V. Bork , D. I. Kazakov , G. S. Vartanov , A. V. Zhiboedov

We review techniques simplifying the analytic calculation of one-loop QCD amplitudes with many external legs, for use in next-to-leading-order corrections to multi-jet processes. Particularly useful are the constraints imposed by…

High Energy Physics - Phenomenology · Physics 2016-09-01 Z. Bern , G. Chalmers , L. Dixon , D. C. Dunbar , D. A. Kosower

By means of a kinematic analysis of tree level graviton amplitudes we find, at least through six points, that the reason of their decompositon as a sum over products of Yang-Mills amplitudes is on-shell gauge invariance and unitarity. As a…

High Energy Physics - Theory · Physics 2020-02-19 Luiz Antonio Barreiro , Ricardo Medina

We argue that the scattering amplitudes in the maximally supersymmetric N=4 super-Yang-Mills theory possess a new symmetry which extends the previously discovered dual conformal symmetry. To reveal this property we formulate the scattering…

High Energy Physics - Theory · Physics 2009-12-22 J. M. Drummond , J. Henn , G. P. Korchemsky , E. Sokatchev

As an alternative to the usual Feynman graphs, tree amplitudes in Yang-Mills theory can be constructed from tree graphs in which the vertices are tree level MHV scattering amplitudes, continued off shell in a particular fashion. The…

High Energy Physics - Theory · Physics 2010-04-07 Freddy Cachazo , Peter Svrcek , Edward Witten

We present a new method for computing complete one-loop amplitudes, including their rational parts, in non-supersymmetric gauge theory. This method merges the unitarity method with on-shell recursion relations. It systematizes a…

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

We derive compact analytical formulae for all tree-level color-ordered gauge theory amplitudes involving any number of external gluons and up to three massless quark-anti-quark pairs. A general formula is presented based on the…

High Energy Physics - Phenomenology · Physics 2011-01-24 Lance J. Dixon , Johannes M. Henn , Jan Plefka , Theodor Schuster

In this article we present a method to generate analytic expressions for the integral coefficients of loop amplitudes using numerical evaluations only. We use high-precision arithmetic to explore the singularity structure of the…

High Energy Physics - Phenomenology · Physics 2023-10-09 Giuseppe De Laurentis , Daniel Maître

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 apply MHV diagrams to the derivation of the one-loop dilatation operator of N=4 super Yang-Mills in the SO(6) sector. We find that in this approach the calculation reduces to the evaluation of a single MHV diagram in dimensional…

High Energy Physics - Theory · Physics 2015-03-05 Andreas Brandhuber , Brenda Penante , Gabriele Travaglini , Donovan Young

We describe an application of generalised unitarity to the computation of one-loop amplitudes with massive external fermions. We present analytic results for the cut-constructible parts of the leading colour contributions to the all-plus…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. D. Badger

Four-point one-loop nonsupersymmetric pure Yang-Mills amplitudes with the duality between color and kinematics manifest have been constructed in previous work. Here, we extend the discussion to fermions and scalars circulating in the loop…

High Energy Physics - Theory · Physics 2015-11-04 Josh Nohle

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