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Related papers: Multi-jet merging with NLO matrix elements

200 papers

We use the SHERPA Monte Carlo generator to simulate the process $e^+e^-\rightarrow\mbox{hadrons}$ using matrix elements with up to six partons in the final state. Two samples of SHERPA events are generated. In the "LO" sample, all final…

High Energy Physics - Experiment · Physics 2018-10-29 Jennifer Kile , Julian von Wimmersperg-Toeller

Multiple-parton interactions play a vital role in hadron-hadron collisions. This paper presents a study of the multiple-parton interactions with simulated Z + jets events in proton-proton collisions at a centre-of-mass energy of 13 TeV. The…

High Energy Physics - Phenomenology · Physics 2019-05-02 M. Bansal , S. Bansal , R. Kumar , J. B. Singh

We present an implementation of the next-to-leading order dijet production process in hadronic collisions in the framework of POWHEG, which is a method to implement NLO calculations within a shower Monte Carlo context. In constructing the…

High Energy Physics - Phenomenology · Physics 2015-05-20 Simone Alioli , Keith Hamilton , Paolo Nason , Carlo Oleari , Emanuele Re

The Matrix Element Method (MEM) has proven beneficial to make maximal use of the information available in experimental data. However, so far it has mostly been used in Born approximation only. In this paper we discuss an extension to NLO…

High Energy Physics - Phenomenology · Physics 2015-11-30 Till Martini , Peter Uwer

A method is detailed for the phase space integration of multi-jets cross sections at lepton colliders, applicable to parton level Monte Carlo's at any order in perturbation theory. Other non-jet objects, massless or massive, can be included…

High Energy Physics - Phenomenology · Physics 2015-04-10 Walter T. Giele

We present an implementation of the vector boson pair production processes ZZ, W+W- and W Z within the POWHEG framework, which is a method that allows the interfacing of NLO calculations to shower Monte Carlo programs. The implementation is…

High Energy Physics - Phenomenology · Physics 2015-05-28 Tom Melia , Paolo Nason , Raoul Röntsch , Giulia Zanderighi

Events containing hadronically decaying heavy particles with large momentum, leading to so-called merged jets, are expected to play a significant role in both searches for new physics and measurements of Standard Model processes at the CERN…

High Energy Physics - Experiment · Physics 2011-09-06 Andrew Altheimer , Gustaaf Brooijmans

In this contribution, we will give a brief overview of the progress that has been achieved in the field of combining matrix elements and parton showers. We exemplify this by focusing on the case of electron--positron collisions and by…

High Energy Physics - Phenomenology · Physics 2012-04-26 Jan Winter , Stefan Hoeche , Hendrik Hoeth , Frank Krauss , Marek Schonherr , Steffen Schumann , Frank Siegert , Korinna Zapp

We introduce a method for matching the neutral-current deep inelastic scattering process with parton showers at first order in the strong coupling. This multiplicative matching is achieved by reweighting leading-order Born-level events and…

High Energy Physics - Phenomenology · Physics 2026-05-13 Ilkka Helenius , Joni O. Laulainen , Christian T. Preuss

In this short note, I introduce to essential conceptual features and main building blocks of matrix element merging algorithms, operating on fixed order calculations both at leading order and next-to-leading order. The intention is purely…

High Energy Physics - Phenomenology · Physics 2015-03-30 Thomas Rössler

We consider the production of a pair of heavy quarks and illustrate the derivation of the MiNNLO method to match next-to-next-to-leading order calculations with parton showers (NNLO+PS) for this class of processes. As a first application,…

High Energy Physics - Phenomenology · Physics 2022-05-04 Javier Mazzitelli , Pier Francesco Monni , Paolo Nason , Emanuele Re , Marius Wiesemann , Giulia Zanderighi

After an introduction to event generators we give an overview of developments in the field of joining matrix elements with parton showers. Starting with matrix element corrections, we also discuss implementations that match LO and NLO…

High Energy Physics - Phenomenology · Physics 2007-05-23 Stefan Gieseke

We propose a scheme that could offer a convenient Monte Carlo sampling of next-to-leading-order matrix elements and, at the same time, allow the interfacing of such parton configurations with a parton-shower approach for the estimation of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Christer Friberg , Torbjörn Sjöstrand

We present an implementation of the production of three jets at NLO plus parton-shower effects in the POWHEG BOX. Using the recently introduced MiNLO procedure for setting the renormalization and factorization scales, we are able to obtain…

High Energy Physics - Phenomenology · Physics 2015-06-18 Adam Kardos , Paolo Nason , Carlo Oleari

The positive weight next-to-leading-order (NLO) matching scheme (POWHEG) is applied to Drell-Yan vector boson production in the Herwig++ Monte Carlo event generator. This approach consistently combines the NLO calculation and parton shower…

High Energy Physics - Phenomenology · Physics 2008-11-26 Keith Hamilton , Peter Richardson , Jon Tully

Recent progress in calculating lepton density functions inside the proton and simulating lepton showers laid the foundations for precision studies of resonant leptoquark production at hadron colliders. Direct quark-lepton fusion into a…

High Energy Physics - Phenomenology · Physics 2022-12-14 Luca Buonocore , Admir Greljo , Peter Krack , Paolo Nason , Nudzeim Selimovic , Francesco Tramontano , Giulia Zanderighi

This paper describes the MC@NLO method for matching next-to-leading order (NLO) perturbative QCD with the parton shower and hadronization model of the Monte Carlo (MC) event generator tt Herwig++, for e+e- annihilation and Drell-Yan lepton…

High Energy Physics - Phenomenology · Physics 2011-03-23 Oluseyi Latunde-Dada

We study in this paper the production, in hadronic collisions, of final states with W gauge bosons, heavy quark pairs and n extra jets (with n up to 4). The complete partonic tree-level QCD matrix elements are evaluated using the ALPHA…

High Energy Physics - Phenomenology · Physics 2008-11-26 Michelangelo L. Mangano , Mauro Moretti , Roberto Pittau

A new method to construct event-generators based on next-to-leading order QCD matrix-elements and leading-logarithmic parton showers is proposed. Matrix elements of loop diagrams as well as those of a tree level can be generated using an…

High Energy Physics - Phenomenology · Physics 2007-05-23 Y. Kurihara

We give a prescription for attaching parton showers to next-to-leading order (NLO) partonic jet cross sections in electron-positron annihilation. Our method effectively extends to NLO the scheme of Catani, Krauss, Kuhn, and Webber for…

High Energy Physics - Phenomenology · Physics 2007-05-23 Zoltan Nagy , Davison E. Soper