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Related papers: Progress in One-Loop QCD Computations

200 papers

An overview is presented on the current status of main mathematical computation methods for the multi-loop corrections to single scale observables in quantum field theory and the associated mathematical number and function spaces and…

High Energy Physics - Phenomenology · Physics 2018-09-19 Johannes Blümlein , Carsten Schneider

We calculate the next-to-leading order (NLO) quantum chromodynamics (QCD) corrections to inclusive processes $W^+\to J/\psi(\eta_c)+c+\bar{s}+X$ and $W^+\to B_c(B_c^{*})+b+\bar{s}+X$ in the framework of nonrelativistic QCD (NRQCD)…

High Energy Physics - Phenomenology · Physics 2020-02-26 Zi-Qiang Chen , Hao Yang , Cong-Feng Qiao

I describe a method for determining the coefficients of scalar integrals for one-loop amplitudes in quantum field theory. The method is based upon generalized unitarity and the behavior of amplitudes when the free parameters of the cut…

High Energy Physics - Phenomenology · Physics 2008-05-12 William B. Kilgore

The integrand-level methods for the reduction of scattering amplitudes are well-established techniques, which have already proven their effectiveness in several applications at one-loop. In addition to the automation and refinement of tools…

High Energy Physics - Phenomenology · Physics 2012-10-05 P. Mastrolia , E. Mirabella , G. Ossola , T. Peraro , H. van Deurzen

An algorithm for an improved description of final-state QCD radiation is introduced. It is matched to the first-order matrix elements for gluon emission in a host of decays, for processes within the Standard Model and the Minimal…

High Energy Physics - Phenomenology · Physics 2009-10-31 Torbjörn Sjöstrand

Lattice QCD studies of hadron-hadron interactions are performed by computing the energy levels of the system in a finite box. The shifts in energy levels proportional to inverse powers of the volume are related to scattering parameters in a…

High Energy Physics - Lattice · Physics 2014-11-17 Paulo F. Bedaque , Ikuro Sato , Andre Walker-Loud

In this talk, we review recent developments towards the calculation of multi-loop scattering amplitudes. In particular, we discuss how the colour-kinematics duality can provide new integral relations at one-loop level via the Loop-Tree…

High Energy Physics - Phenomenology · Physics 2018-01-10 William J. Torres Bobadilla

The four-dimensional helicity regularization scheme is often used in one-loop QCD computations. It was recently argued in Ref. [1] that this scheme is inconsistent beyond the one-loop order in perturbation theory. In this paper, we clarify…

High Energy Physics - Phenomenology · Physics 2011-09-29 Radja Boughezal , Kirill Melnikov , Frank Petriello

As a first step towards the computation of the NLO corrections to the photon impact factor in the $\gamma^*\gamma^* \to \gamma^* \gamma^*$ scattering process, we calculate the one loop corrections to the coupling of the reggeized gluon to…

High Energy Physics - Phenomenology · Physics 2014-11-17 J. Bartels , S. Gieseke , C. -F. Qiao

We recompute the functions describing the collinear factorization of one-loop amplitudes using the unitarity-based method. We present the results in a form suitable for use as an ingredient in two-loop calculations. We also present a…

High Energy Physics - Phenomenology · Physics 2008-11-26 David A. Kosower , Peter Uwer

In this talk we describe the recursive Approach to One-loop QCD Matrix Elements.

High Energy Physics - Phenomenology · Physics 2009-11-11 N. E. J. Bjerrum-Bohr , David C. Dunbar , Harald Ita

I formulate in a colour-friendly way the FKS method for the computation of QCD cross sections at the next-to-leading order accuracy. This is achieved through the definition of subtraction terms for squared matrix elements, constructed with…

High Energy Physics - Phenomenology · Physics 2021-06-25 Stefano Frixione

We present the computer code RECOLA for the computation of EW and QCD amplitudes in the Standard Model at next-to-leading order. One-loop amplitudes are represented as linear combinations of tensor integrals whose coefficients are…

High Energy Physics - Phenomenology · Physics 2013-11-27 Stefano Actis , Ansgar Denner , Lars Hofer , Andreas Scharf , Sandro Uccirati

After briefly introducing the framework of QCD factorization for B-> M1 M2 in the language of the Soft-Collinear Effective Theory, we firstly address the recent efforts on higher-order radiative corrections in QCD factorization. Then we…

High Energy Physics - Phenomenology · Physics 2014-11-20 Deshan Yang

We calculate the one-loop correction to the soft-gluon current with massive fermions. This current is process independent and controls the singular behavior of one-loop massive QCD amplitudes in the limit when one external gluon becomes…

High Energy Physics - Phenomenology · Physics 2015-05-28 Isabella Bierenbaum , Michal Czakon , Alexander Mitov

Techniques based upon the string organisation of amplitudes may be used to simplify field theory calculations. We apply these techniques to perturbative gravity and calculate all one-loop amplitudes for four-graviton scattering with…

High Energy Physics - Theory · Physics 2009-10-28 David C. Dunbar , Paul S. Norridge

This article reviews on-shell methods for analytic computation of loop amplitudes, emphasizing techniques based on unitarity cuts. Unitarity techniques are formulated generally but have been especially useful for calculating one-loop…

High Energy Physics - Theory · Physics 2015-05-20 Ruth Britto

The public code GOSAM for the computation of the one loop virtual corrections to scattering amplitudes in the Standard Model and beyond is presented. Particular emphasis is devoted to the interface with other public tools via the Binoth Les…

High Energy Physics - Phenomenology · Physics 2012-10-01 F. Tramontano

The lectures are a practical introduction to perturbative calculations in QED and QCD. I discuss methods of calculation of one- and two-loop diagrams in dimensional regularization, MSbar and on-shell renormalization schemes, decoupling of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Andrey Grozin

Light cone perturbation theory has become an essential tool to calculate cross sections for various small-$x$ dilute-dense processes such as deep inelastic scattering and forward proton-proton and proton-nucleus collisions. Here we set out…

High Energy Physics - Phenomenology · Physics 2017-04-05 Tuomas Lappi , Risto Paatelainen