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Related papers: Multi-jet merging with NLO matrix elements

200 papers

We review the key features of POWHEG, a method for interfacing parton-shower Monte Carlo generators to fixed next-to-leading order QCD computations. We describe a recently introduced framework, the POWHEG-BOX, that allows the automatic…

High Energy Physics - Phenomenology · Physics 2010-12-13 Carlo Oleari

One of the most important developments in Monte Carlo simulation of collider events for the LHC has been the arrival of schemes and codes for matching of parton showers to matrix elements calculated at next-to-leading order in the QCD…

High Energy Physics - Phenomenology · Physics 2017-12-21 Andy Buckley , Debottam Bakshi Gupta

We present precise predictions for prompt photon production in association with a $Z$ boson and jets. They are obtained within the Sherpa framework as a consistently merged inclusive sample. Leptonic decays of the $Z$ boson are fully…

High Energy Physics - Phenomenology · Physics 2018-04-04 Johannes Krause , Frank Siegert

We make a thorough comparison between different schemes of merging fixed-order tree-level matrix element generators with parton-shower models. We use the most basic benchmark of the O(alpha_S) correction to e+e- -> jets, where the simple…

High Energy Physics - Phenomenology · Physics 2009-04-30 Nils Lavesson , Leif Lonnblad

We present an implementation of the next-to-leading order vector boson plus one jet production process in hadronic collision in the framework of POWHEG, which is a method to implement NLO calculations within a Shower Monte Carlo context.…

High Energy Physics - Phenomenology · Physics 2011-02-01 Simone Alioli , Paolo Nason , Carlo Oleari , Emanuele Re

The next-to-leading order accuracy for MC@NLO results exclusive in J light jets is achieved if the computation is based on matrix elements that feature J and J+1 QCD partons. The simultaneous prediction of observables which are exclusive in…

High Energy Physics - Phenomenology · Physics 2015-06-11 Rikkert Frederix , Stefano Frixione

We present a consistent way of combining associated weak boson radiation in hard dijet events with hard QCD radiation in Drell-Yan-like scatterings. This integrates multiple tree-level calculations with vastly different cross sections, QCD-…

High Energy Physics - Phenomenology · Physics 2016-02-17 Jesper Roy Christiansen , Stefan Prestel

We revisit the CKKW-L method for merging tree-level matrix elements with parton showers, and amend it with an add/subtract scheme to minimise dependencies on the merging scale. The scheme is constructed to, as far as possible, recover the…

High Energy Physics - Phenomenology · Physics 2015-06-12 Leif Lonnblad , Stefan Prestel

We present a simulation program for the production of a pair of W bosons in association with a jet, that can be used in conjunction with general-purpose shower Monte Carlo generators, according to the POWHEG method. We have further adapted…

High Energy Physics - Phenomenology · Physics 2016-10-12 Keith Hamilton , Tom Melia , Pier Francesco Monni , Emanuele Re , Giulia Zanderighi

We propose a simple scheme to start a parton-shower evolution description from a given jet configuration in $e^+ e^-$ annihilation events. This allows a convenient combination of the full angular information content of matrix elements with…

High Energy Physics - Phenomenology · Physics 2011-01-13 J. André , T. Sjöstrand

We present an implementation of electroweak W+W-jj production at hadron colliders in the POWHEG framework, a method that allows the interfacing of a next-to-leading order QCD calculation with parton shower Monte Carlo programs. We provide…

High Energy Physics - Phenomenology · Physics 2015-06-12 Barbara Jager , Giulia Zanderighi

We extend the multi-purpose Monte-Carlo event generator Sherpa to include processes in deeply inelastic lepton-nucleon scattering. Hadronic final states in this kinematical setting are characterised by the presence of multiple kinematical…

High Energy Physics - Phenomenology · Physics 2015-09-22 Tancredi Carli , Thomas Gehrmann , Stefan Höche

The matrix element method usually employs leading-order matrix elements. We discuss the generalisation towards higher orders in perturbation theory and show how the matrix element method can be used at next-to-leading order for arbitrary…

High Energy Physics - Phenomenology · Physics 2017-03-01 Robin Baumeister , Stefan Weinzierl

We present an implementation of the calculation of the production of W^+W^+ plus two jets at hadron colliders, at next-to-leading order (NLO) in QCD, in the POWHEG framework, which is a method that allows the interfacing of NLO calculations…

High Energy Physics - Phenomenology · Physics 2015-05-27 Tom Melia , Paolo Nason , Raoul Rontsch , Giulia Zanderighi

I review recent developments in POWHEG, a method for interfacing parton-shower generators with NLO QCD computations. I illustrate recent progress in understanding several features of the method, and in clarifying similarity and differences…

High Energy Physics - Phenomenology · Physics 2010-01-18 P. Nason

We propose a general approach for the description of multijet events in the framework of QCD event generators. We introduce a new algorithm to match parton showers and arbitrary matrix elements for the production of any number of jets via…

High Energy Physics - Phenomenology · Physics 2009-10-31 F. Krauss , R. Kuhn , G. Soff

Azimuthal correlations between the two jets with the largest transverse momenta $ {p_{\mathrm{T}}} $ in inclusive 2-, 3-, and 4-jet events are presented for several regions of the leading jet $ {p_{\mathrm{T}}} $ up to 4 TeV. For 3- and…

High Energy Physics - Experiment · Physics 2018-07-12 CMS Collaboration

A Monte-Carlo event-generator has been developed which is dedicated to simulate electron-positron annihilations. Especially a new approach for the combination of matrix elements and parton showers ensures the independence of the…

High Energy Physics - Phenomenology · Physics 2017-08-23 R. Kuhn , A. Schaelicke , F. Krauss , G. Soff

We present a generator for lepton nucleon collisions in the DIS regime, focusing in particular on processes with a massive lepton and/or a massive quark in the final state. We have built a full code matching NLO QCD corrections to parton…

High Energy Physics - Phenomenology · Physics 2024-06-10 Luca Buonocore , Giovanni Limatola , Paolo Nason , Francesco Tramontano

We discuss the GENEVA Monte Carlo framework, which combines higher-order resummation (NNLL) of large Sudakov logarithms with multiple next-to-leading-order (NLO) matrix-element corrections and parton showering (using PYTHIA8) to give a…