English
Related papers

Related papers: Augmented Recursion For One-loop Amplitudes

200 papers

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

The seven-gluon two-loop full-color Yang-Mills amplitude is presented in a compact analytic form where we use the methods of four-dimensional unitarity cuts to obtain the polylogarithmic pieces and augmented recursion to obtain the rational…

High Energy Physics - Phenomenology · Physics 2025-01-14 Adam R. Dalgleish , David C. Dunbar , Warren B. Perkins , Joseph M. W. Strong

We present an analytic reconstruction of one-loop amplitudes for the process $0 \to \bar{q}qt\bar{t}H$. Our calculation is a novel use of analytic reconstruction, retaining explicit covariance in the massive spin states through the massive…

High Energy Physics - Phenomenology · Physics 2025-07-28 John M. Campbell , Giuseppe De Laurentis , R. Keith Ellis

We propose a first implementation of the integrand-reduction method for two-loop scattering amplitudes. We show that the residues of the amplitudes on multi-particle cuts are polynomials in the irreducible scalar products involving the loop…

High Energy Physics - Phenomenology · Physics 2015-05-30 Pierpaolo Mastrolia , Giovanni Ossola

Recently we conjectured the four-point amplitude of graviton multiplets in ${\rm AdS}_5 \times {\rm S}^5$ at one loop by exploiting the operator product expansion of $\mathcal{N}=4$ super Yang-Mills theory. Here we give the first extension…

High Energy Physics - Theory · Physics 2018-06-13 F. Aprile , J. M. Drummond , P. Heslop , H. Paul

We present an algorithm for the numerical calculation of one-loop QCD amplitudes. The algorithm consists of subtraction terms, approximating the soft, collinear and ultraviolet divergences of one-loop amplitudes and a method to deform the…

High Energy Physics - Phenomenology · Physics 2010-12-09 Sebastian Becker , Christian Reuschle , Stefan Weinzierl

We describe the unitarity approach for the numerical computation of two-loop integral coefficients of scattering amplitudes. It is well known that the leading propagator singularities of an amplitude's integrand are related to products of…

High Energy Physics - Phenomenology · Physics 2017-06-07 S. Abreu , F. Febres Cordero , H. Ita , M. Jaquier , B. Page

We review the conventional field theory description of the string motivated technique. This technique is applied to the one-loop five-gluon amplitude. To evaluate the amplitude a general method for computing dimensionally regulated one-loop…

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

Explicit expressions for one-loop five supergraviton scattering amplitudes in both type II superstring theories are determined by making use of the pure spinor formalism. The type IIB amplitude can be expressed in terms of a doubling of…

High Energy Physics - Theory · Physics 2015-06-16 Michael B. Green , Carlos R. Mafra , Oliver Schlotterer

We describe a general method that enables us to obtain all the singular terms of helicity amplitudes of n-parton processes at one loop. The algorithm uses helicity amplitudes at tree level and simple color algebra. We illustrate the method…

High Energy Physics - Phenomenology · Physics 2009-10-28 Zoltan Kunszt , Adrian Signer , Zoltan Trocsanyi

We consider a Higgs boson coupled to gluons via the five-dimensional effective operator H tr G_{\mu\nu}G^{\mu\nu}. We treat H as the real part of a complex field phi that couples to the selfdual gluon field strengths and compute the…

High Energy Physics - Phenomenology · Physics 2009-02-09 E. W. N. Glover , Pierpaolo Mastrolia , Ciaran Williams

In four dimensions, it has long been established that gravity coupled to matter exhibits ultraviolet divergences at one loop, irrespective of supersymmetry. Notably, the four-matter one-loop amplitudes of half-maximal supergravity coupled…

High Energy Physics - Theory · Physics 2026-04-02 Yu-tin Huang , Henrik Johansson , Michele Santagata , Congkao Wen

Generalised bi-adjoint scalar amplitudes, obtained from integrations over moduli space of punctured $\mathbb{CP}^{k-1}$, are novel extensions of the CHY formalism. These amplitudes have realisations in terms of Grassmannian cluster…

High Energy Physics - Theory · Physics 2021-05-19 Md. Abhishek , Subramanya Hegde , Arnab Priya Saha

A covariant path integral calculation of the even spin structure contribution to the one-loop N-graviton scattering amplitude in the type-II superstring theory is presented. The apparent divergence of the $N=5$ amplitude is resolved by…

High Energy Physics - Theory · Physics 2015-06-26 J. Lee Montag

We calculate gauge theory one-loop amplitudes with the aid of the complex shift used in the Britto-Cachazo-Feng-Witten (BCFW) recursion relations of tree amplitudes. We apply the shift to the integrand and show that the contribution from…

High Energy Physics - Theory · Physics 2013-05-30 Savan Kharel , George Siopsis

We propose a new ``universal expansion" for one-loop amplitudes with arbitrary number of gluons in $D$ dimensions, which holds for general gauge theories with gluons/fermions/scalars in the loop, including pure and supersymmetric Yang-Mills…

High Energy Physics - Theory · Physics 2024-12-30 Qu Cao , Jin Dong , Song He , Fan Zhu

We present an ansatz for all one-loop amplitudes in pure Einstein gravity for which the n external gravitons have the same outgoing helicity. These loop amplitudes, which are rational functions of the momenta, also arise in the quantization…

High Energy Physics - Theory · Physics 2010-11-15 Z. Bern , L. Dixon , M. Perelstein , J. S. Rozowsky

We consider the covariant proposal for the gravitational Compton amplitude for a Kerr black hole. Employing the covariant three- and four-point Compton amplitudes, we assemble the classical one-loop integrand on the maximal cut at all…

High Energy Physics - Theory · Physics 2024-12-30 Gang Chen , Tianheng Wang

We revisit the quantum-amplitude-based derivation of the gravitational waveform emitted by the scattering of two spinless massive bodies at the third order in Newton's constant, $h \sim G+G^2+G^3$ (one-loop level), and correspondingly…

High Energy Physics - Theory · Physics 2024-06-24 Donato Bini , Thibault Damour , Stefano De Angelis , Andrea Geralico , Aidan Herderschee , Radu Roiban , Fei Teng

The one loop gluon - W-meson amplitude is calculated by means of the gauge-invariant generalized Pauli-Villars regularization and with the help of dimensional regularization. It is shown that in the former case the amplitude satisfies…

High Energy Physics - Theory · Physics 2009-10-31 M. M. Deminov , A. A. Slavnov