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Related papers: Multiparton NLO corrections by numerical methods

200 papers

We present the calculation of next-to-next-to-leading-order (NNLO) QCD corrections to hadron multiplicities in light-quark jets at lepton colliders, employing the ``projection-to-Born" (P2B) method implemented in the FMNLO program. Taking…

High Energy Physics - Phenomenology · Physics 2025-10-29 Bin Zhou , Jun Gao

We present next-to-leading order corrections in the leading colour approximation for jet rates in electron-positron annihilation up to seven jets. The results for the two-, three-, and four-jet rates agree with known results. The NLO jet…

High Energy Physics - Phenomenology · Physics 2013-05-30 Sebastian Becker , Daniel Goetz , Christian Reuschle , Christopher Schwan , Stefan Weinzierl

We perform the integration of all iterated singly-unresolved subtraction terms, as defined in ref. [1], over the two-particle factorized phase space. We also sum over the unresolved parton flavours. The final result can be written as a…

High Energy Physics - Phenomenology · Physics 2011-05-10 Paolo Bolzoni , Gabor Somogyi , Zoltan Trocsanyi

We present a new general algorithm for calculating arbitrary jet cross sections in arbitrary scattering processes to next-to-leading accuracy in perturbative QCD. The algorithm is based on the subtraction method. The key ingredients are new…

High Energy Physics - Phenomenology · Physics 2009-10-28 Stefano Catani , Michael H. Seymour

We calculate the NNLO QED corrections to the $C$-even part of differential cross section of $e^+e^- \to \mu^+\mu^-$ process. We neglect power corrections in the electron mass and obtain the result in terms of Goncharov's polylogarithms.

High Energy Physics - Phenomenology · Physics 2025-05-15 Roman E. Gerasimov , Petr A. Krachkov , Roman N. Lee

We present results for the O(alpha_s) virtual corrections to q g -> W b bbar q' obtained with a new automatized approach to the evaluation of one-loop amplitudes in terms of Feynman diagrams. Together with the O(alpha_s) corrections to q q'…

High Energy Physics - Phenomenology · Physics 2015-05-30 Laura Reina , Thomas Schutzmeier

We report on the analytic calculation of the second-order QCD corrections to semi-inclusive hadron production in electron-positron annihilation. The calculation of the single-particle inclusive cross-section in time-like kinematics is…

High Energy Physics - Phenomenology · Physics 2014-12-22 Alexander Mitov , Sven-Olaf Moch

We present the NLO QCD corrections to the production of a photon pair in association with one jet, where the photons are stemming from graviton decay, within models of large extra dimensions. Our results for the loop amplitudes are produced…

High Energy Physics - Phenomenology · Physics 2015-06-16 Nicolas Greiner , Gudrun Heinrich , Joscha Reichel , Johann Felix von Soden-Fraunhofen

We present an optimization of the reduction algorithm of one-loop amplitudes in terms of master integrals. It is based on the exploitation of the polynomial structure of the integrand when evaluated at values of the loop-momentum fulfilling…

High Energy Physics - Phenomenology · Physics 2008-11-26 P. Mastrolia , G. Ossola , C. G. Papadopoulos , R. Pittau

We present analytic results for the one-loop corrections of the helicity amplitudes of the QCD five-parton subprocesses involving four quarks and one gluon obtained with a standard Feynman diagram calculation using dimensional reduction.

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

We present a new implementation of the NNLO QCD corrections to three-jet final states and related event-shape observables in electron--positron annihilation. Our implementation is based on the antenna subtraction method, and is performed in…

High Energy Physics - Phenomenology · Physics 2017-12-06 Thomas Gehrmann , Nigel Glover , Alexander Huss , Jan Niehues , Hantian Zhang

I review progress related to the calculation of QCD jet cross sections at the NLO accuracy. After a short introduction into the theory of NLO calculations, I discuss two recent developments: the calculation of two- and three-jet…

High Energy Physics - Phenomenology · Physics 2013-05-29 Zoltan Trocsanyi

We briefly describe a new general algorithm for carrying out QCD calculations to next-to-leading order in perturbation theory. The algorithm can be used for computing arbitrary jet cross sections in arbitrary processes and can be…

High Energy Physics - Phenomenology · Physics 2007-05-23 Stefano Catani , Michael H. Seymour

We present the integrand reduction via multivariate polynomial division as a natural technique to encode the unitarity conditions of Feynman amplitudes. We derive a recursive formula for the integrand reduction, valid for arbitrary…

High Energy Physics - Phenomenology · Physics 2015-06-16 P. Mastrolia , E. Mirabella , G. Ossola , T. Peraro

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

In this article we illustrate how event weights for jet events can be calculated efficiently at next-to-leading order (NLO) accuracy in QCD. This is a crucial prerequisite for the application of the Matrix Element Method in NLO. We modify…

High Energy Physics - Phenomenology · Physics 2015-09-18 Till Martini , Peter Uwer

We establish an efficient polynomial-complexity algorithm for one-loop calculations, based on generalized $D$-dimensional unitarity. It allows automated computations of both cut-constructible {\it and} rational parts of one-loop scattering…

High Energy Physics - Phenomenology · Physics 2009-09-17 Walter T. Giele , Zoltan Kunszt , Kirill Melnikov

We review progress in calculating one-loop scattering amplitudes required for next-to-leading-order corrections to QCD processes. The underlying technical developments include the spinor helicity formalism, color decompositions,…

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

We compute the one-loop QCD amplitude for the process gg-->Q\bar{Q} in dimensional regularization through order \epsilon^2 in the dimensional regulator and for arbitrary quark mass values. This result is an ingredient of the NNLO…

High Energy Physics - Phenomenology · Physics 2008-12-30 Charalampos Anastasiou , S. Mert Aybat

The ALPHA algorithm to evaluate the exact, tree-level matrix elements is reviewed in the context of multi-parton processes in QCD. The algorithm is suited for the authomatic calculation of tree-level scattering amplitudes and allows for…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Moretti