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Related papers: One-Loop Amplitudes in Supersymmetric QCD from MHV…

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Using twistor space intuition, Cachazo, Svrcek and Witten presented novel diagrammatic rules for gauge-theory amplitudes, expressed in terms of maximally helicity-violating (MHV) vertices. We define non-MHV vertices, and show how to use…

High Energy Physics - Theory · Physics 2009-11-10 I. Bena , Z. Bern , D. A. Kosower

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 generalize modern ideas about the duality between Wilson loops and scattering amplitudes in ${\cal N}$=4 SYM to large-N (or quenched) QCD. We show that the area-law behavior of asymptotically large Wilson loops is dual to the…

High Energy Physics - Theory · Physics 2009-02-27 Yuri Makeenko , Poul Olesen

We identify a large class of one-loop amplitudes for massless particles that can be constructed via unitarity from tree amplitudes, without any ambiguities. One-loop amplitudes for massless supersymmetric gauge theories fall into this…

High Energy Physics - Phenomenology · Physics 2010-11-15 Z. Bern , L. Dixon , D. C. Dunbar , D. A. Kosower

For scattering amplitudes in strong background fields, it is -- at least in principle -- possible to perturbatively expand the background to obtain higher-point vacuum amplitudes. In the case of self-dual plane wave backgrounds we consider…

High Energy Physics - Theory · Physics 2022-01-19 Tim Adamo , Anton Ilderton , Alexander J. MacLeod

QCD amplitudes with many external fields have been studied for a long time. At tree-level, the amplitudes can be obtained effectively by the BCFW recursion relations. In this article, we extend the Britto-Cachazo-Feng-Witten (BCFW)…

High Energy Physics - Theory · Physics 2015-03-19 Gang Chen

$\mathcal{N}=1$ supersymmetric QCD (SQCD) is a possible building block of theories beyond the standard model. It describes the interaction between gluons and quarks with their superpartners, gluinos and squarks. Since supersymmetry is…

High Energy Physics - Lattice · Physics 2018-11-06 Björn Wellegehausen , Andreas Wipf

We present advances in the development of the numerical unitarity method for the computation of multi-loop amplitudes in QCD. As an application, we show results for all the leading-color two-loop five-gluon helicity amplitudes. The…

High Energy Physics - Phenomenology · Physics 2018-07-26 Samuel Abreu , Fernando Febres Cordero , Harald Ita , Ben Page , Mao Zeng

Recent discoveries in supersymmetric gauge theories have significant implications for our understanding for QCD and of field theory in general. The phases of N=1 supersymmetric QCD (SQCD) are discussed, and the possibility of similar phases…

High Energy Physics - Lattice · Physics 2008-11-26 Matthew J. Strassler

We investigate generic properties of one-loop amplitudes in unordered gauge theories in four dimensions. For such theories the organisation of amplitudes in manifestly crossing symmetric expressions poses restrictions on their structure and…

High Energy Physics - Theory · Physics 2012-05-03 Simon Badger , N. E. J. Bjerrum-Bohr , Pierre Vanhove

We use the infrared consistency of one-loop amplitudes in N=4 Yang-Mills theory to derive a compact analytic formula for a tree-level NNMHV gluon scattering amplitude in QCD, the first such formula known. We argue that the IR conditions,…

High Energy Physics - Theory · Physics 2009-11-10 Radu Roiban , Marcus Spradlin , Anastasia Volovich

The high-energy scattering amplitude of two colour-singlet quark-antiquark pairs is governed by the correlation function of two Wilson loops, which follow the classical straight lines for quark (antiquark) trajectories. This quantity is…

High Energy Physics - Phenomenology · Physics 2009-11-10 E. Meggiolaro

We argue that generic one-loop scattering amplitudes in supersymmetric Yang-Mills theories can be computed equivalently with MHV diagrams or with Feynman diagrams. We first present a general proof of the covariance of one-loop non-MHV…

High Energy Physics - Theory · Physics 2009-11-11 Andreas Brandhuber , Bill Spence , Gabriele Travaglini

We compute the one-loop QCD amplitude for the process gg-->Q\bar{Q} in dimensional regularization through order \epsilon^2 in the dimensional regulator and for arbitrary quark mass values. This result is an ingredient of the NNLO…

High Energy Physics - Phenomenology · Physics 2008-12-30 Charalampos Anastasiou , S. Mert Aybat

Using N=1 Supersymmetric QCD (SQCD) as a prototype model, this work presents a formulation of overlap quarks and gluinos on the lattice, with particular emphasis on the construction of chirally symmetric Yukawa terms. By incorporating the…

High Energy Physics - Lattice · Physics 2025-07-23 Marios Costa , Eleni Ioannou , Haralambos Panagopoulos

This article reviews on-shell methods for analytic computation of loop amplitudes, emphasizing techniques based on unitarity cuts. Unitarity techniques are formulated generally but have been especially useful for calculating one-loop…

High Energy Physics - Theory · Physics 2015-05-20 Ruth Britto

The infrared exponentiation properties of dimensionally-regularized multi-loop scattering amplitudes are typically hidden at the level of the integrand, materializing only after integral evaluation. We address this long-standing problem by…

High Energy Physics - Theory · Physics 2019-07-22 Robert M. Schabinger

One loop corrections to the helicity amplitudes of all 2 -> 2 subprocesses are calculated in QCD and in N=1 supersymmetric Yang-Mills theory using two versions of dimensional regularization: the `t~Hooft-Veltman scheme and dimensional…

High Energy Physics - Phenomenology · Physics 2009-10-22 Zoltan Kunszt , Adrian Signer , Zoltán Trócsányi

Prompted by recent progress in the study of N=4 super Yang-Mills amplitudes, and evidence that similar approaches might be relevant to N=8 supergravity, we investigate possible iterative structures and applications of Wilson loop techniques…

High Energy Physics - Theory · Physics 2008-11-26 Andreas Brandhuber , Paul Heslop , Adele Nasti , Bill Spence , Gabriele Travaglini

We compute the one-loop expectation value of light-like polygonal Wilson loops in N=4 super-Yang-Mills theory in full superspace. When projecting to chiral superspace we recover the known results for tree-level…

High Energy Physics - Theory · Physics 2012-06-18 Niklas Beisert , Song He , Burkhard U. W. Schwab , Cristian Vergu