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Related papers: Seven parton amplitudes from recursion relations

200 papers

We review recent developments in the calculation of QCD loop amplitudes with several external legs, and their application to next-to-leading order jet production cross-sections. When a number of calculational tools are combined together ---…

High Energy Physics - Phenomenology · Physics 2007-05-23 Z. Bern , L. Dixon , D. A. Kosower , A. Signer

We consider the multi-collinear limit of multi-gluon QCD amplitudes at tree level. We use the MHV rules for constructing colour ordered tree amplitudes and the general collinear factorisation formula to derive timelike splitting functions…

High Energy Physics - Phenomenology · Physics 2007-05-23 P. Marquard , T. G. Birthwright

New methods are introduced for the description and evaluation of tree-level gravitational scattering amplitudes. An N=7 super-symmetric recursion, free from spurious double poles, gives a more efficient method for evaluating MHV amplitudes.…

High Energy Physics - Theory · Physics 2011-08-26 Andrew Hodges

We analyze the off-shell scattering amplitudes in the framework of the light-front perturbation theory. It is shown that the previously derived recursion relation between tree level off-shell amplitudes in this formalism actually resums…

High Energy Physics - Phenomenology · Physics 2015-06-24 C. Cruz-Santiago , P. Kotko , A. Stasto

We perform a comprehensive study of on-shell recursion relations for Born amplitudes in spontaneously broken gauge theories and identify the minimal shifts required to construct amplitudes with a given particle content and spin quantum…

High Energy Physics - Theory · Physics 2020-02-19 Robert Franken , Christian Schwinn

We study the application of non-trivial relations between gravity tree amplitudes, the bonus relations, to all tree-level amplitudes in N=8 supergravity. We show that the relations can be used to simplify explicit formulae of supergravity…

High Energy Physics - Theory · Physics 2011-02-16 Song He , Dhritiman Nandan , Congkao Wen

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

Two new formulas which express n-graviton MHV tree amplitudes in terms of sums of squares of n-gluon amplitudes are discussed. The first formula is derived from recursion relations. The second formula, simpler because it involves fewer…

High Energy Physics - Theory · Physics 2009-06-19 Henriette Elvang , Daniel Z. Freedman

We recursively construct tree-level electromagnetic and gravitational Compton amplitudes of higher-spin massive particles by the all-line transverse momentum shift. With three-point amplitude as input, we demonstrate that higher-point…

High Energy Physics - Theory · Physics 2025-06-04 Yohei Ema , Ting Gao , Wenqi Ke , Zhen Liu , Ishmam Mahbub

We apply the on-shell tree-level recursion relations of Britto, Cachazo, Feng and Witten to a variety of processes involving internal and external massive particles with spin. We show how to construct multi-vector boson currents where one…

High Energy Physics - Theory · Physics 2009-11-11 S. D. Badger , E. W. N. Glover , Valentin V. Khoze

We propose to make use of the off-shell recursive relations with the color-flow decomposition in the calculation of QCD amplitudes on MadGraph. We introduce colored quarks and their interactions with nine gluons in the color-flow basis plus…

High Energy Physics - Phenomenology · Physics 2011-06-08 Kaoru Hagiwara , Yoshitaro Takaesu

One of the methods to calculate tree-level multi-gluon scattering amplitudes is to use the Berends-Giele recursion relation involving off-shell currents or off-shell amplitudes, if working in the light cone gauge. As shown in recent works…

High Energy Physics - Phenomenology · Physics 2016-08-24 Piotr Kotko , Mirko Serino , Anna M. Stasto

We illustrate the use of recursion relations in the computation of certain one-loop helicity amplitudes containing an arbitrary number of gauge bosons. After a brief review of the recursion relations themselves, we discuss the resolution of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Gregory Mahlon

The recently developed on-shell bootstrap for computing one-loop amplitudes in non-supersymmetric theories such as QCD combines the unitarity method with loop-level on-shell recursion. For generic helicity configurations, the recursion…

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

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 compute amplitudes for the process $g^* g^* \to q \overline q V^*$ (two virtual gluons into a quark, antiquark and a boson) at the tree level using the spinor-helicity formalism. The resulting analytic expressions are much shorter than…

High Energy Physics - Phenomenology · Physics 2024-10-11 Jan Ferdyan , Błażej Ruba

We derive an on-shell diagram recursion for tree-level scattering amplitudes in $\mathcal{N}=7$ supergravity. The diagrams are evaluated in terms of Grassmannian integrals and momentum twistors, generalising previous results of Hodges in…

High Energy Physics - Theory · Physics 2021-05-12 Connor Armstrong , Joseph A. Farrow , Arthur E. Lipstein

We provide a new set of on-shell recursion relations for tree-level scattering amplitudes, which are valid for any non-trivial theory of massless particles. In particular, we reconstruct the scattering amplitudes from (a subset of) their…

High Energy Physics - Theory · Physics 2015-05-28 Paolo Benincasa , Eduardo Conde

We evaluate all split helicity gluon tree amplitudes in open twistor string theory. We show that these amplitudes satisfy the BCFW recurrence relations restricted to the split helicity case and, hence, that these amplitudes agree with those…

High Energy Physics - Theory · Physics 2012-09-10 Louise Dolan , Peter Goddard

We review the current status of high-multiplicity double-virtual QCD corrections to processes relevant for LHC phenomenology. In particular, we discuss the recent full-color calculation of the five-parton process, whose two-loop amplitudes…

High Energy Physics - Phenomenology · Physics 2024-06-27 Giuseppe De Laurentis