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Related papers: One-loop amplitudes with an off-shell gluon

200 papers

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

We compute one-loop electron-photon vertex with fully off-shell external momenta in an arbitrary covariant gauge and space-time dimension. There exist numerous efforts in literature where one-loop off-shell vertex is calculated by employing…

High Energy Physics - Phenomenology · Physics 2023-04-10 Victor Miguel Banda Guzmán , Adnan Bashir

Using recent advances in the understanding of non-critical strings, we construct a unique, conformally invariant continuation to off-shell momenta of Polyakov amplitudes in critical string theory. Three-point amplitudes are explicitly…

High Energy Physics - Theory · Physics 2011-07-19 Robert C. Myers , Vipul Periwal

We compute the one-loop amplitude for a Higgs boson, a quark-antiquark pair and a pair of gluons of negative helicity, i.e. for the next-to-maximally helicity violating (NMHV) case, A(H, qbar-, q+, g-, g-). The calculation is performed…

High Energy Physics - Phenomenology · Physics 2009-12-17 Simon Badger , John M. Campbell , R. Keith Ellis , Ciaran Williams

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

A prescription is presented to construct manifestly gauge invariant tree-level scattering amplitudes with one or two off-shell initial-state gluons for processes with arbitrary particles in the final state, which allows for calculations…

High Energy Physics - Phenomenology · Physics 2013-07-09 A. van Hameren

We use on-shell recursion relations to compute analytically the one-loop corrections to maximally-helicity-violating n-gluon amplitudes in QCD. The cut-containing parts have been computed previously; our work supplies the remaining rational…

High Energy Physics - Phenomenology · Physics 2008-11-26 Carola F. Berger , Zvi Bern , Lance J. Dixon , Darren Forde , David A. Kosower

Results on the one-loop quark-gluon vertex with massive quarks are reviewed, in an arbitrary covariant gauge and in arbitrary space-time dimension. We show how it is possible to get on-shell results from the general off-shell expressions.…

High Energy Physics - Phenomenology · Physics 2009-10-31 A. I. Davydychev , P. Osland , L. Saks

We compute the one-loop QCD amplitudes for the decay of an off-shell vector boson with vector couplings into a quark-antiquark pair accompanied by two gluons keeping, for the first time, all orders in the number of colours. Together with…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. M. Campbell , E. W. N. Glover , D. J. Miller

We present a model calculation of the T-odd transverse momentum dependent (TMD) gluon fragmentation functions for a spin-1/2 hadron. Our model is based on the postulation that a time-like off-shell gluon can fragment into a hadron and a…

High Energy Physics - Phenomenology · Physics 2024-05-21 Xiupeng Xie , Zhun Lu

We present an overview of recent developments, based on on-shell techniques, in the calculation of multi-parton scattering amplitudes at one loop that are relevant for phenomenological studies at hadron colliders. These new on-shell methods…

High Energy Physics - Phenomenology · Physics 2015-05-14 Carola F. Berger , Darren Forde

An efficient numerical algorithm to evaluate one-loop amplitudes using tensor integrals is presented. In particular, it is shown by explicit calculations that for ordered QCD amplitudes with a number of external legs up to 10, its…

High Energy Physics - Phenomenology · Physics 2009-08-11 A. van Hameren

We give, in the framework of the bosonic string theory, simple prescriptions for computing, at tree and one-loop levels, off-shell string amplitudes for open and closed string massless states. In particular we obtain a tree amplitude for…

High Energy Physics - Theory · Physics 2014-11-18 L. Cappiello , A. Liccardo , R. Pettorino , F. Pezzella , R. Marotta

For nearly fifty years theoretical and experimental efforts in nucleon-nucleon bremsstrahlung (NN$\gamma$) have been devoted to measuring off-shell amplitudes and distinguishing among various NN potentials on the basis of their off-shell…

Nuclear Theory · Physics 2009-10-30 Harold W. Fearing

We present results for one-loop corrections to the recently introduced "gluon condensate" PDF $F(x)$. In particular, we give expression for the $gg$-part of its evolution kernel. To enforce strict compliance with the gauge invariance…

High Energy Physics - Phenomenology · Physics 2021-12-22 Anatoly Radyushkin , Shuai Zhao

Recent progress in the computation of one-loop gluon amplitudes is reviewed. These methods were originally derived from superstring theory and are significantly more efficient than conventional Feynman rules. With these methods, explicit…

High Energy Physics - Phenomenology · Physics 2007-05-23 Zvi Bern

We describe techniques that simplify the calculation of one-loop QCD amplitudes with many external legs, which are needed for next-to-leading-order (NLO) corrections to multi-jet processes. The constraints imposed by perturbative unitarity,…

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

For the case of $n$-jet production at next-to-next-to-leading order in the QCD coupling, in the infrared divergent corners of phase space where particles are collinear or soft, one must evaluate $(n+1)$-parton final-state one-loop…

High Energy Physics - Phenomenology · Physics 2008-11-26 Zvi Bern , Vittorio Del Duca , Carl R. Schmidt

In this paper we consider tree-level gauge invariant off-shell amplitudes (Wilson line form factors) in $\mathcal{N}=4$ SYM with arbitrary number of off-shell gluons or equivalently Wilson line operator insertions. We make a conjecture for…

High Energy Physics - Theory · Physics 2018-02-20 L. V. Bork , A. I. Onishchenko

We present the one-loop helicity amplitudes with five external gluons. The computation employs string-based methods, new techniques for performing tensor integrals, and improvements in the spinor helicity method.

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