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Related papers: Matching parton showers to NLO computations

200 papers

We analyze the effects of jet algorithms on each factorized part of the dijet cross sections in $e^+ e^-$ scattering using the soft-collinear effective theory. The jet function and the soft function with a cone-type jet algorithm and the…

High Energy Physics - Phenomenology · Physics 2015-08-19 Junegone Chay , Chul Kim , Inchol Kim

Standard dipole parton showers are known to yield incorrect subleading-colour contributions to the leading (double) logarithmic terms for a variety of observables. In this work, concentrating on final-state showers, we present two simple,…

High Energy Physics - Phenomenology · Physics 2021-07-29 Keith Hamilton , Rok Medves , Gavin P. Salam , Ludovic Scyboz , Gregory Soyez

We report work on the matching of the next-to-leading logarithmic approximation (NLLA) onto the fixed next-to-next-to-leading order (NNLO) calculation for event shape variables in electron-positron annihilation. The correction of the…

High Energy Physics - Phenomenology · Physics 2008-10-21 T. Gehrmann , G. Luisoni , H. Stenzel

We consider $W^\pm Z$ production in hadronic collisions and present high-precision predictions in QCD and electroweak (EW) perturbation theory matched to parton showers. To this end, we match next-to-next-to-leading order QCD corrections to…

High Energy Physics - Phenomenology · Physics 2022-11-30 Jonas M. Lindert , Daniele Lombardi , Marius Wiesemann , Giulia Zanderighi , Silvia Zanoli

A modified version of the CKKW matrix element merging algorithm is presented, suitable for use in an angular-ordered parton shower, using truncated showers and forced splittings. The algorithm is implemented in the Herwig++ Monte Carlo…

High Energy Physics - Phenomenology · Physics 2009-11-13 Keith Hamilton , Peter Richardson , Jon Tully

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

We use the known soft and collinear limits of tree- and one-loop scattering amplitudes -- computed over a decade ago -- to explicitly construct a subtraction scheme for next-to-next-to-leading order (NNLO) computations. Our approach…

High Energy Physics - Phenomenology · Physics 2015-06-03 Radja Boughezal , Kirill Melnikov , Frank Petriello

I present a general purpose Monte Carlo program for calculating the next-to-leading order corrections to arbitrary four-jet quantities in electron-positron annihilation. In the current version of the program, some subleading in color terms…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Signer

The method to merge matrix elements for multi particle production and parton showers in electron-positron annihilations and hadronic collisions and its implementation into the new event generator SHERPA is described in detail. Examples…

High Energy Physics - Phenomenology · Physics 2009-11-11 Andreas Schaelicke , Frank Krauss

We present the matching of NLO QCD and NLO EW corrections to parton showers for vector-boson pair production at the LHC. We consider leptonic final states, including resonant and non-resonant diagrams, spin correlations and off-shell…

High Energy Physics - Phenomenology · Physics 2020-09-24 Mauro Chiesa , Carlo Oleari , Emanuele Re

Results for the two real parton differential distributions needed for implementing a next-to-leading order (NLO) parton shower Monte Carlo are presented. They are also integrated over the phase space in order to provide solid numerical…

High Energy Physics - Phenomenology · Physics 2011-08-10 S. Jadach , A. Kusina , M. Skrzypek , M. Slawinska

This lecture discusses the physics implemented by Monte Carlo event generators for hadron colliders. It details the construction of parton showers and the matching of parton showers to fixed-order calculations at higher orders in…

High Energy Physics - Phenomenology · Physics 2015-06-19 Stefan Höche

We reveal the direct link between the jet clustering algorithms recently proposed by Howard Georgi and parton shower kinematics, providing firm foundation from the theoretical side. The kinematics of this class of elegant algorithms is…

High Energy Physics - Phenomenology · Physics 2015-06-11 Shao-Feng Ge

In this review, we discuss the results on the parton-to-pion fragmentation functions obtained in a combined NLO fit to data of single-inclusive hadron production in electron-positron annihilation, proton-proton collisions, and…

High Energy Physics - Phenomenology · Physics 2016-11-23 R. J. Hernández-Pinto , M. Epele , D. de Florian , R. Sassot , M. Stratmann

The next-to-leading order (NLO) corrections to Drell-Yan slepton pair production are merged with parton shower evolution via the POWHEG method in Herwig++. The NLO corrections at the level of event generation alter the shape of observables…

High Energy Physics - Phenomenology · Physics 2012-08-02 Ilan Fridman-Rojas , Peter Richardson

We study electron-positron annihilations into six jets at the parton level in perturbative Quantum Chromo-Dynamics. We use helicity amplitude methods. Results are presented for the case of the Durham and Cambridge jet clustering algorithms…

High Energy Physics - Phenomenology · Physics 2009-10-30 Stefano Moretti

We present a selection of results from our recent study of $pp\to t\bar{t}W^\pm$ production matched to partons showers at NLO QCD at the LHC. Theoretical predictions are obtained at perturbative orders $\mathcal{O}(\alpha_s^3\alpha)$ and…

High Energy Physics - Phenomenology · Physics 2021-10-26 Manfred Kraus

We have calculated the splitting functions governing the evolution of the unpolarized parton distributions of the photon at the next-to-next-to-leading order (NNLO) of massless perturbative QCD. The results, presented here mainly in terms…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Vogt , S. Moch , J. Vermaseren

We compare different procedures for combining fixed-order tree-level matrix-element generators with parton showers. We use the case of W-production at the Tevatron and the LHC to compare different implementations of the so-called CKKW and…

In this work, we present the extension of an alternative subtraction scheme for next-to-leading order QCD calculations to the case of an arbitrary number of massless final-state partons. The scheme is based on the splitting kernels of an…

High Energy Physics - Phenomenology · Physics 2013-05-29 Cheng Han Chung , Tania Robens