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Related papers: On-shell two-loop three-gluon vertex

200 papers

We present results for the six-gluon scattering amplitude at one-loop. Since our method is semi-numerical, it yields the result for arbitrary momenta and helicities of the external gluons. We evaluate the colour-ordered sub-amplitudes with…

High Energy Physics - Phenomenology · Physics 2009-11-11 R. K. Ellis , W. T. Giele , Giulia Zanderighi

We present a grapical way to describe invariants and covariants in the (4 dim) general relativity. This makes us free from the complexity of suffixes . Two new off-shell relations between (mass)$\ast\ast 6$\ invariants are obtained. These…

High Energy Physics - Theory · Physics 2010-04-06 Shoichi Ichinose

We investigate the Dyson-Schwinger equations for the gluon and ghost propagators and the ghost-gluon vertex of Landau-gauge gluodynamics in two dimensions. While this simplifies some aspects of the calculations as compared to three and four…

High Energy Physics - Theory · Physics 2012-11-20 Markus Q. Huber , Axel Maas , Lorenz von Smekal

In the context of the Standard Model we extend the S--matrix pinch technique for non--conserved currents to the case of three boson vertices. We outline in detail how effective gauge invariant three boson vertices can be constructed, with…

High Energy Physics - Phenomenology · Physics 2009-10-28 J. Papavassiliou , K. Philippides

We compute two-loop corrections to the associated production of a Higgs boson with a $Z$ boson and to off-shell $Z$ boson pair production in the gluon fusion channel, mediated by a heavy quark. We perform deep expansions in the high-energy…

High Energy Physics - Phenomenology · Physics 2025-09-10 Joshua Davies , Dominik Grau , Kay Schönwald , Matthias Steinhauser , Daniel Stremmer , Marco Vitti

We give a construction of off-shell tree bosonic string amplitudes, based on the operatorial formalism of the $N$-string Vertex, with three external massless states both for open and closed strings by requiring their being projective…

High Energy Physics - Theory · Physics 2009-10-31 A. Liccardo , F. Pezzella , R. Marotta

Off-shell Ward identities in non-abelian gauge theory continue to be a subject of active research, since they are, in general, inhomogeneous and their form depends on the chosen gauge-fixing procedure. For the three-gluon and four-gluon…

High Energy Physics - Theory · Physics 2020-08-26 Naser Ahmadiniaz , Christian Schubert

The off-shell and the on-shell Sudakov form factors in theories with broken gauge symmetry are calculated in the double-logarithmic approximation. We have used different infrared cut-offs, i.e. different mass scales, for virtual photons and…

High Energy Physics - Theory · Physics 2007-05-23 A. Barroso , B. I. Ermolaev

When scattering amplitudes are calculated in the double-logarithmic approximation, it is possible to relate the double-logarithmic on-shell and off-shell amplitudes. Explicit relations are obtained for scattering amplitudes in QED, QCD, and…

High Energy Physics - Phenomenology · Physics 2008-11-26 B. I. Ermolaev , M. Greco , F. Olness , S. I. Troyan

In this work, a covariant formulation of the gluon self-energy in presence of ellipsoidal anisotropy is considered. It is shown that the general structure of the gluon self-energy can be written in terms of six linearly independent…

High Energy Physics - Phenomenology · Physics 2020-12-09 Ritesh Ghosh , Bithika Karmakar , Arghya Mukherjee

We calculate the two-loop vertex function for the crossed topology, and for arbitrary masses and external momenta. We derive a double integral representation, suitable for a numerical evaluation by a Gaussian quadrature. Real and imaginary…

High Energy Physics - Phenomenology · Physics 2009-10-28 A. Frink , U. Kilian , D. Kreimer

We present the two-loop matrix elements for the scattering of two gluons into two photons in QCD. These matrix elements will enter into improved estimates of the QCD background to Higgs production at the LHC when the Higgs decays into two…

High Energy Physics - Phenomenology · Physics 2010-02-03 Z. Bern , A. De Freitas , L. Dixon

This study examines on-shell supersymmetry breaking in the Abelian $\mathcal{N}=1$ Chern-Simons-matter model within a three-dimensional spacetime. The classical Lagrangian is scale-invariant, but two-loop radiative corrections to the…

High Energy Physics - Theory · Physics 2023-05-22 A. C. Lehum

The leading short-distance contributions to hadronic hard-scattering cross sections in the operator product expansion are described by twist-two quark and gluon operators. The anomalous dimensions of these operators determine the splitting…

High Energy Physics - Phenomenology · Physics 2024-12-02 Thomas Gehrmann , Andreas von Manteuffel , Tong-Zhi Yang

In all mass cases needed for quark and gluon self-energies, the two-loop master diagram is expanded at large and small $q^2$, in $d$ dimensions, using identities derived from integration by parts. Expansions are given, in terms of…

High Energy Physics - Phenomenology · Physics 2011-08-17 D. J. Broadhurst , J. Fleischer , O. V. Tarasov

We use twistor inspired rules to compute the one-loop amplitude for a Higgs boson coupling to any number of negative helicity gluons in the large top mass limit.

High Energy Physics - Phenomenology · Physics 2008-11-26 S. D. Badger , E. W. N. Glover

We compute the quark-gluon vertex in quenched lattice QCD, in the Landau gauge using an off-shell mean-field O(a)-improved fermion action. The Dirac-vector part of the vertex is computed for arbitrary kinematics. We find a substantial…

High Energy Physics - Lattice · Physics 2008-11-26 Ayse Kizilersu , Derek B. Leinweber , Jon-Ivar Skullerud , Anthony G. Williams

We consider a class of on-shell constrained mass variables that are 3+1 dimensional generalizations of the Cambridge $M_{T2}$ variable and that automatically incorporate various assumptions about the underlying event topology. The presence…

High Energy Physics - Phenomenology · Physics 2015-03-26 Won Sang Cho , James S. Gainer , Doojin Kim , Konstantin T. Matchev , Filip Moortgat , Luc Pape , Myeonghun Park

I present calculations of two-loop vertex corrections with massive and massless partons in the eikonal approximation. I show that the $n$-loop result for the UV poles can be given in terms of the one-loop calculation.

High Energy Physics - Phenomenology · Physics 2007-05-23 Nikolaos Kidonakis

We compute the four-gluon vertex from the Curci-Ferrari model at one-loop order for a collinear configuration. Our results display a good agreement with the first lattice data for this vertex, released very recently (arXiv:2401.12008). A…

High Energy Physics - Theory · Physics 2024-05-08 Nahuel Barrios , Philipe De Fabritiis , Marcela Peláez