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Related papers: Unitarity-based Techniques for One-Loop Calculatio…

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We have calculated the one-loop scattering amplitude of an electron by an external Coulomb potential in QED free of infrared divergences. This feature is achieved by applying the Faddeev-Kulish formalism, which implies a redefinition of…

High Energy Physics - Phenomenology · Physics 2024-11-15 J. A. Oller , Marcela Peláez

A precise understanding of LHC phenomenology requires the inclusion of one-loop corrections for multi-particle final states. In this talk we describe a semi-numerical method to compute one-loop amplitudes with many external particles and…

High Energy Physics - Phenomenology · Physics 2009-11-11 T. Binoth , M. Ciccolini , G. Heinrich

We construct a specific formalism for calculating the one-loop virtual corrections for standard model processes with an arbitrary number of external legs. The procedure explicitly separates the infrared and ultraviolet divergences…

High Energy Physics - Phenomenology · Physics 2009-11-10 W. T. Giele , E. W. N. Glover

I discuss recent progress in the calculation of two-loop QCD corrections in the eikonal approximation. I present specific results for the UV structure of the corrections.

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

We discuss applications of the proper-time method in various minimal Lorentz violating modifications of QED and present new results obtained with its use. Explicitly. we calculate the complete one-loop Heisenberg-Euler effective action…

High Energy Physics - Theory · Physics 2023-02-17 A. F. Ferrari , J. Furtado , J. F. Assunção , T. Mariz , A. Yu. Petrov

We present the one-loop QCD amplitudes for two external massless quarks and three external gluons ($\bar{q}qggg$). This completes the set of one-loop amplitudes needed for the next-to-leading-order corrections to three-jet production at…

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

Recent results and methods of three-loop calculations in HQET are reviewed.

High Energy Physics - Phenomenology · Physics 2008-11-26 A. G. Grozin

We compute the leading color, next-to-leading order QCD corrections to the dominant partonic channels for the production of a W boson in association with three jets at the Tevatron and the LHC. This is the first application of generalized…

High Energy Physics - Phenomenology · Physics 2010-01-07 R. Keith Ellis , Kirill Melnikov , Giulia Zanderighi

We present advances in the development of the numerical unitarity method for the computation of multi-loop amplitudes in QCD. As an application, we show results for all the leading-color two-loop five-gluon helicity amplitudes. The…

High Energy Physics - Phenomenology · Physics 2018-07-26 Samuel Abreu , Fernando Febres Cordero , Harald Ita , Ben Page , Mao Zeng

We report on two recent multiloop results in QED: (i) the four-loop corrections to the conversion relations between the QED charge renormalized in the on-shell and MS-bar schemes; (ii) analytical evaluation of a class of asymptotic…

High Energy Physics - Phenomenology · Physics 2008-11-26 P. A. Baikov , K. G. Chetyrkin , C. Sturm

In this talk we discuss an algorithm for the numerical calculation of one-loop QCD amplitudes and present results at next-to-leading order for jet observables in electron-positron annihilation calculated with the above-mentioned method. The…

High Energy Physics - Phenomenology · Physics 2011-12-16 S. Becker , D. Goetz , C. Reuschle , C. Schwan , S. Weinzierl

The state-of-the-art in current two-loop QCD amplitude calculations is at five-particle scattering. Computing two-loop six-particle processes requires knowledge of the corresponding one-loop amplitudes to higher orders in the dimensional…

High Energy Physics - Theory · Physics 2023-02-08 Johannes M. Henn , Antonela Matijašić , Julian Miczajka

Recent Developments in computing very specific helicity amplitudes in two loop QCD are presented. The techniques focus upon the singular structure of the amplitude rather than on a diagramatic and integration approach

High Energy Physics - Phenomenology · Physics 2017-12-15 David C. Dunbar , John H Godwin , Guy R. Jehu , Warren B. Perkins

We report on the next-to-leading order QCD calculation for e+ e- --> 4 jets. We explain some modern techniques which have been used to calculate the one-loop amplitudes efficiently. We further report on the general purpose numerical program…

High Energy Physics - Phenomenology · Physics 2008-11-26 Stefan Weinzierl

We review on-shell methods for computing multi-parton scattering amplitudes in perturbative QCD, utilizing their unitarity and factorization properties. We focus on aspects which are useful for the construction of one-loop amplitudes needed…

High Energy Physics - Phenomenology · Physics 2010-11-15 Zvi Bern , Lance J. Dixon , David A. Kosower

In this review some recent multi-loop results obtained in the framework of perturbative Quantum Chromodynamics (QCD) and Quantum Electrodynamics (QED) are discussed. After reviewing the most advanced techniques used for the computation of…

High Energy Physics - Phenomenology · Physics 2009-11-07 M. Steinhauser

We calculate the one-loop QCD corrections for the decay of an off-shell vector boson with vector couplings into two pairs of quarks of equal or unequal flavours keeping all orders in the number of colours. These matrix elements are relevant…

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

In the last few years, much progress has been made in the computation of one-loop virtual matrix elements for processes involving many external particles. In this contribution the methods that have enabled this recent progress are briefly…

High Energy Physics - Phenomenology · Physics 2011-04-20 D. Maitre

I illustrate new techniques and recently obtained results in the computation of perturbative QCD processes at the NLO accuracy

High Energy Physics - Phenomenology · Physics 2011-11-30 Roberto Pittau

We consider the singular behaviour of one-loop QCD matrix elements when several external partons become simultaneously parallel. We present a new factorization formula that describes the singular collinear behaviour directly in colour…

High Energy Physics - Phenomenology · Physics 2010-04-05 Stefano Catani , Daniel de Florian , German Rodrigo