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Related papers: Multiparton NLO corrections by numerical methods

200 papers

I review the state-of-the-art for fully differential numerical NNLO programs. Topics which are covered include the calculation of two-loop amplitudes, multiple polylogarithms, cancellation of infra-red divergences at NNLO and the efficient…

High Energy Physics - Phenomenology · Physics 2009-11-11 Stefan Weinzierl

We compute the next-to-leading-power corrections in the $N$-jettiness variable to the production of a prompt photon and a jet at next-to-leading order in perturbative QCD in the $q \bar q$ annihilation channel. We employ the $k_\perp$ jet…

High Energy Physics - Phenomenology · Physics 2025-10-06 Prem Agarwal , Kirill Melnikov , Ivan Pedron

A new method of calculation of amplitudes of different processes in quantum electrodynamics is proposed. The method does not use the Feynman technique of trace of product of matrices calculation. The method strongly simplifies calculation…

High Energy Physics - Phenomenology · Physics 2015-06-05 Kostyantyn Karplyuk , Oleksandr Zhmudsky

The rational parts of 5-gluon one-loop amplitudes are computed by using the newly developed method for computing the rational parts directly from Feynman integrals. We found complete agreement with the previously well-known results of Bern,…

High Energy Physics - Phenomenology · Physics 2008-11-26 Xun Su , Zhi-Guang Xiao , Gang Yang , Chuan-Jie Zhu

Calculation of amplitudes in perturbative quantum field theory involve large loop integrals. The complexity of those integrals, in combination with the large number of Feynman diagrams, make the calculations very difficult. Reduction…

High Energy Physics - Phenomenology · Physics 2015-06-05 Ronald H. P. Kleiss , Ioannis Malamos , Costas G. Papadopoulos , Rob Verheyen

We consider direct diphoton production in hadron collisions, and we compute the next-to-next-to-leading order (NNLO) QCD radiative corrections at the fully-differential level. Our calculation uses the $q_T$ subtraction formalism and it is…

High Energy Physics - Phenomenology · Physics 2016-06-27 Stefano Catani , Leandro Cieri , Daniel de Florian , Giancarlo Ferrera , Massimiliano Grazzini

In this publication the construction of an automatic algorithm to subtract infrared divergences in real QCD corrections through the Catani-Seymour dipole subtraction method [arXiv:hep-ph/9605323] is reported. The resulting computer code has…

High Energy Physics - Phenomenology · Physics 2008-11-26 Tanju Gleisberg , Frank Krauss

In this talk we report on first results from the NLO computation of Z production in association with five jets in hadron-hadron collisions. The results are obtained with the help of the numerical method, where apart from the phase space…

High Energy Physics - Phenomenology · Physics 2014-07-02 Daniel Goetz , Christian Reuschle , Christopher Schwan , Stefan Weinzierl

A c++ implementation of the D_s-dimensional unitarity cut algorithm for the numerical evaluation of the virtual contribution to NLO QCD amplitudes is presented. The current version includes an arbitrary number of external gluons with…

High Energy Physics - Phenomenology · Physics 2008-12-17 A. Lazopoulos

The unitarity method for calculating one-loop amplitudes provides algorithms of polynomial complexity. This is primarily beneficial for the computation of multi-leg one loop amplitudes and it is therefore of great interest to develop a…

High Energy Physics - Phenomenology · Physics 2009-04-14 R. Keith Ellis , Walter T. Giele , Zoltan Kunszt

We use the known values of the two loop Wilson coefficients and the three loop anomalous dimension matrix $\gamma(n)$ to perform a next-to-next-to leading order (NNLO) calculation of $ep$ deep inelastic scattering. Because $\gamma(n)$ is…

High Energy Physics - Phenomenology · Physics 2009-10-31 J. Santiago , F. J. Yndurain

The complete set of Feynman rules for the rational part R of QCD corrections in the MSSM are calculated at the one-loop level, which can be very useful in the next-to-leading order calculations in supersymmetric models. Our results are…

High Energy Physics - Phenomenology · Physics 2015-06-05 Hua-Sheng Shao , Yu-Jie Zhang

We discuss how the multi-Regge factorisation of QCD amplitudes can be used in the study of multi-jet processes at colliders. We describe how the next-to-leading logarithmic (NLL) BFKL evolution can be combined with energy and momentum…

High Energy Physics - Phenomenology · Physics 2017-08-23 Jeppe R. Andersen

We present a numerical implementation for virtual corrections to multi-jet production at Next-to-Leading order. Using the algorithm of generalised unitarity we compute primitive amplitudes from tree-level input. These basic ingredients are…

High Energy Physics - Phenomenology · Physics 2012-01-06 Simon Badger , Benedikt Biedermann , Peter Uwer

Based on the NRQCD factorization formalism, we calculate the next-to-next-to-leading order QCD corrections to the heavy quarkonium $\eta_c (\eta_b)$ production associated with a photon at electron-positron colliders. By matching the…

High Energy Physics - Phenomenology · Physics 2018-02-14 Long-Bin Chen , Yi Liang , Cong-Feng Qiao

We compute for the first time the production rate for four jets in electron-positron annihilation at next-to-next-to-leading order. Our calculation exhibits the highest final-state jet multiplicity considered at this perturbative accuracy…

High Energy Physics - Phenomenology · Physics 2026-02-23 Xuan Chen , Dmitry Chicherin , Elliot Fox , Nigel Glover , Matteo Marcoli , Vasily Sotnikov , Huiting Sun , Hantian Zhang , Simone Zoia

We provide a complete and detailed study of the high-energy limit of four-parton scattering amplitudes in QCD, giving explicit results at two loops and higher orders, and going beyond next-to-leading logarithmic (NLL) accuracy. Building…

High Energy Physics - Phenomenology · Physics 2015-06-23 Vittorio Del Duca , Giulio Falcioni , Lorenzo Magnea , Leonardo Vernazza

We present the Master Integrals needed for the calculation of the two-loop QCD corrections to the forward-backward asymmetry of a quark-antiquark pair produced in electron-positron annihilation events. The abelian diagrams entering in the…

High Energy Physics - Phenomenology · Physics 2009-11-10 R. Bonciani , P. Mastrolia , E. Remiddi

The moments of the single inclusive momentum distribution of hadrons in QCD jets, are studied in the next-to-modified-leading-log approximation (NMLLA) including next-to-leading-order (NLO) corrections to the alpha_s strong coupling. The…

High Energy Physics - Phenomenology · Physics 2014-08-18 Redamy Perez-Ramos , David d'Enterria

We complete the computation of the two-loop helicity amplitudes for the production of three photons at hadron colliders, including all contributions beyond the leading-color approximation. We reconstruct the analytic form of the amplitudes…

High Energy Physics - Phenomenology · Physics 2023-10-16 Samuel Abreu , Giuseppe De Laurentis , Harald Ita , Maximillian Klinkert , Ben Page , Vasily Sotnikov