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Related papers: Numerical evaluation of NLO multiparton processes

200 papers

We review some of the recent advances in the computation of one-loop scattering amplitudes which led to the construction of efficient and automated computational tools for NLO predictions. Particular attention is devoted to unitarity-based…

High Energy Physics - Phenomenology · Physics 2015-06-17 Giovanni Ossola

We present a general subtraction scheme for NNLO calculations in massless QCD: the \textit{colourful antenna subtraction method}. It is a reformulation of the antenna subtraction approach designed to address some of the limitations of the…

High Energy Physics - Phenomenology · Physics 2024-12-06 T. Gehrmann , E. W. N. Glover , M. Marcoli

A method based on sector decomposition has been developed to calculate the double real radiation part of the process e+e- to 3 jets at next-to-next-to-leading order. It is shown in an example that the numerical cancellation of soft and…

High Energy Physics - Phenomenology · Physics 2009-01-07 G. Heinrich

We propose a new approach that allows for the separate numerical calculation of the real and imaginary parts of finite loop integrals. We find that at one-loop the real part is given by the Loop-Tree Duality integral supplemented with…

High Energy Physics - Phenomenology · Physics 2022-02-01 Dario Kermanschah

It is described how the method of sector decomposition can serve to disentangle overlapping infrared singularities, in particular those occurring in the calculation of the real emission part of e+e- to 2 jets and e+e- to 3 jets at NNLO.

High Energy Physics - Phenomenology · Physics 2009-11-10 G. Heinrich

We present a semi-numerical method to compute one-loop corrections to processes involving many particles. We treat in detail cases with up to five external legs and massless internal propagators, although the method is more general.

High Energy Physics - Phenomenology · Physics 2008-11-26 G. Zanderighi

We present a new method for the numerical evaluation of arbitrary loop integrals in dimensional regularization. We first derive Mellin-Barnes integral representations and apply an algorithmic technique, based on the Cauchy theorem, to…

High Energy Physics - Phenomenology · Physics 2009-11-11 Charalampos Anastasiou , Alejandro Daleo

We report on a new method for the numerical evaluation of loop integrals, based on the Feynman Tree Theorem. The loop integrals are replaced by phase-space integration over fictitious extra on-shell particles. This integration can be…

High Energy Physics - Phenomenology · Physics 2010-02-08 Wolfgang Kilian , Tobias Kleinschmidt

We consider the class of inclusive hadron collider processes in which one or more energetic jets are produced, possibly accompanied by colourless particles. We provide a general formulation of a slicing scheme for this class of processes,…

High Energy Physics - Phenomenology · Physics 2024-05-15 Luca Buonocore , Massimiliano Grazzini , Jürg Haag , Luca Rottoli , Chiara Savoini

We describe the calculation of the next-to-next-to-leading order (NNLO) QCD corrections to three-jet production and related event shape observables in electron-positron annihilation. Infrared singularities due to double real radiation at…

High Energy Physics - Phenomenology · Physics 2008-12-30 A. Gehrmann-De Ridder , T. Gehrmann , E. W. N. Glover , G. Heinrich

We present a formalism for the calculation of multi-particle one-loop amplitudes, valid for an arbitrary number N of external legs, and for massive as well as massless particles. A new method for the tensor reduction is suggested which…

High Energy Physics - Phenomenology · Physics 2013-12-16 T. Binoth , J. Ph. Guillet , G. Heinrich , E. Pilon , C. Schubert

The calculation of hard scattering amplitudes up to NLO is automated in numerical tools, such as OpenLoops. The LHC and future experiments, however, demand high-precision predictions at NNLO and beyond for a wide range of particle…

High Energy Physics - Phenomenology · Physics 2024-12-20 Natalie Schär , Max F. Zoller

We propose a new method of computing real emission contributions to hard QCD processes. Our approach uses sector decomposition of the exclusive final-state phase space to enable extraction of all singularities of the real emission matrix…

High Energy Physics - Phenomenology · Physics 2008-11-26 C. Anastasiou , Kirill Melnikov , Frank Petriello

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

We present the colourful antenna subtraction method, a reformulation of the antenna subtraction scheme for next-to-next-to-leading order (NNLO) calculations in QCD. The aim of this new approach is to achieve a general and…

High Energy Physics - Phenomenology · Physics 2022-03-28 Xuan Chen , Thomas Gehrmann , Nigel Glover , Alexander Huss , Matteo Marcoli

In a previous paper a new approach has been introduced for computing, recursively and numerically, one-loop tensor integrals. Here we describe a few modifications of the original method that allow a more efficient numerical implementation…

High Energy Physics - Phenomenology · Physics 2007-05-23 R. Pittau

We describe the details of the calculation of the full colour NNLO QCD corrections to jet production observables at the LHC with antenna subtraction. All relevant matrix elements for the process $pp \to jj$ at NNLO in full colour are…

High Energy Physics - Phenomenology · Physics 2022-10-26 X. Chen , T. Gehrmann , E. W. N. Glover , J. Mo

We propose a method for computing numerically integrals defined via $i \epsilon$ deformations acting on single-pole singularities. We achieve this without an explicit analytic contour deformation. Our solution is then used to produce…

High Energy Physics - Phenomenology · Physics 2022-01-21 Roberto Pittau , Bryan Webber

We report on the sector decomposition approach to the double real radiation part of e^+e^- to 3 jets at NNLO.

High Energy Physics - Phenomenology · Physics 2009-11-11 G. Heinrich

We present a semi-numerical algorithm to calculate one-loop virtual corrections to scattering amplitudes. The divergences of the loop amplitudes are regulated using dimensional regularization. We treat in detail the case of amplitudes with…

High Energy Physics - Phenomenology · Physics 2008-11-26 R. K. Ellis , W. T. Giele , G. Zanderighi