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Related papers: Seven parton amplitudes from recursion relations

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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

We compare four different methods for the numerical computation of the pure gluonic amplitudes in the Born approximation. We are in particular interested in the efficiency of the various methods as the number n of the external particles…

High Energy Physics - Phenomenology · Physics 2009-11-11 Michael Dinsdale , Marko Ternick , Stefan Weinzierl

Following~\cite{Arkani-Hamed:2017thz}, we derive a recursion relation by applying a one-parameter deformation of kinematic variables for tree-level scattering amplitudes in bi-adjoint $\phi^3$ theory. The recursion relies on properties of…

High Energy Physics - Theory · Physics 2019-05-28 Song He , Qinglin Yang

Basing on the Slavnov-Taylor identities, we derive a new prescription to obtain gauge invariant tree-level scattering amplitudes for the process g*g->Ng within high energy factorization. Using the helicity method, we check the formalism up…

High Energy Physics - Phenomenology · Physics 2013-01-18 Andreas van Hameren , Piotr Kotko , Krzysztof Kutak

We extend a recently discovered set of relations for gauge-theory amplitudes to non-gluonic matter. For all MHV amplitudes we find that these can be made to hold for scalar/fermion/quark cases by inclusion of a factor derived via Ward…

High Energy Physics - Theory · Physics 2009-08-11 Thomas Sondergaard

We study scalar one-loop amplitudes in massive $\phi^3$-theory within causal loop-tree duality. We derive a recurrence relation for the integrand of the amplitude. The integrand is by construction free of spurious singularities on…

High Energy Physics - Theory · Physics 2022-10-07 Sascha Kromin , Niklas Schwanemann , Stefan Weinzierl

This report describes the recent efforts to compute analytic formulae for the Next-to-Leading-Order (NLO) QCD corrections to Higgs plus two jet production at hadron colliders. In these calculations the Higgs boson couples to gluons via a…

High Energy Physics - Phenomenology · Physics 2014-11-20 Ciaran Williams

We present the first explicit formulae for the complete set of one-loop helicity amplitudes necessary for computing next-to-leading order corrections for e^+ e^- annihilation into four jets, for W, Z or Drell-Yan production in association…

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

We present MHV-rules for constructing perturbative amplitudes for a Higgs boson and an arbitrary number of partons. We give explicit expressions for amplitudes involving a Higgs and three negative helicity partons and any number of positive…

High Energy Physics - Theory · Physics 2011-01-13 S. D. Badger , E. W. N. Glover , Valentin V. Khoze

In this note we further investigate the procedure for computing tree-level amplitudes in Yang-Mills theory from connected instantons in the B-model on P^{3|4}, emphasizing that the problem of calculating Feynman diagrams is recast into the…

High Energy Physics - Theory · Physics 2011-05-05 Radu Roiban , Marcus Spradlin , Anastasia Volovich

We consider a Higgs boson coupled to gluons via the five-dimensional effective operator H Tr G_{munu}G^{munu} produced by considering the heavy top quark limit of the one-loop coupling of Higgs and gluons in the standard model. We treat H…

High Energy Physics - Phenomenology · Physics 2009-04-21 S. D. Badger , E. W. N. Glover , Kasper Risager

As continuation of our previous paper we further develop our new method for calculating helicity amplitudes of jet-like QED processes described by tree diagrams, applying it to lepton pair production. This method consists in replacing…

High Energy Physics - Phenomenology · Physics 2011-09-13 C. Carimalo , A. Schiller , V. G. Serbo

We consider a scalar field, such as the Higgs boson H, coupled to gluons via the effective operator H tr G_{mu nu} G^{mu nu} induced by a heavy-quark loop. We treat H as the real part of a complex field phi which couples to the self-dual…

High Energy Physics - Phenomenology · Physics 2014-11-18 Carola F. Berger , Vittorio Del Duca , Lance J. Dixon

Recently, it has been shown that on-shell scattering amplitudes can be constructed by the Feynman-tree theorem combined with the BCFW recursion relations. Since the BCFW relations are restricted to tree diagrams, the preceding application…

High Energy Physics - Theory · Physics 2018-03-20 Markos Maniatis

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

A method to define and calculate one-loop amplitudes with an off-shell space-like, or $k_T$-dependent, gluon is presented. It introduces a practical regularization to deal with the divergencies that appear due to linear denominators, and…

High Energy Physics - Phenomenology · Physics 2022-02-01 A. van Hameren

We present new relations for scattering amplitudes of color ordered gluons, massive quarks and scalars minimally coupled to gravity. Tree-level amplitudes of arbitrary matter and gluon multiplicities involving one graviton are reduced to…

High Energy Physics - Theory · Physics 2018-07-18 Jan Plefka , Wadim Wormsbecher

We construct a modified on-shell BCFW recursion relation to derive compact analytic representations of tree-level amplitudes in QED. As an application, we study the amplitudes of a fermion pair coupling to an arbitrary number of photons and…

High Energy Physics - Phenomenology · Physics 2014-11-21 Simon Badger , Johannes M. Henn

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 define recursion relations for N = 8 supergravity amplitudes using a generalization of the on-shell diagrams developed for planar N = 4 super-Yang-Mills. Although the recursion relations generically give rise to non-planar on-shell…

High Energy Physics - Theory · Physics 2016-06-29 Paul Heslop , Arthur E. Lipstein