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Related papers: Multijet events and parton showers

200 papers

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…

This paper presents a new event generator, ALPGEN, dedicated to the study of multiparton hard processes in hadronic collisions. The code performs, at the leading order in QCD and EW interactions, the calculation of the exact matrix elements…

High Energy Physics - Phenomenology · Physics 2009-11-07 M. L. Mangano , M. Moretti , F. Piccinini , R. Pittau , A. D. Polosa

Recent top quark event modeling studies done using LHC proton-proton collision data collected with the CMS detector at centre of mass energies of 8 and 13 TeV and state-of-the-art theoretical predictions are summarized. A new factorized…

High Energy Physics - Experiment · Physics 2018-07-01 Efe Yazgan

We present a method to match the multi-parton states generated by the High Energy Jets Monte Carlo with parton showers generated by the Ariadne program using the colour dipole model. The High Energy Jets program already includes a full…

High Energy Physics - Phenomenology · Physics 2015-03-19 Jeppe R. Andersen , Leif Lonnblad , Jennifer M. Smillie

We extend earlier schemes for merging tree-level matrix elements with parton showers to include also merging with one-loop matrix elements. In this paper we make a first study on how to include one-loop corrections, not only for events with…

High Energy Physics - Phenomenology · Physics 2009-02-02 Nils Lavesson , Leif Lonnblad

Jet quenching - the modification of high-energy jets in the quark-gluon plasma - has been extensively studied through weakly coupled scattering amplitudes embedded in parton-shower frameworks. These models, often combined with bulk…

High Energy Physics - Phenomenology · Physics 2026-04-10 Ismail Soudi , Adam Takacs

We aim to improve the modelling of deep inelastic scattering by implementing multi-jet merging capabilities in Vincia parton shower in the general-purpose Monte Carlo event generator, Pythia. Merging allows to combine event samples of…

High Energy Physics - Phenomenology · Physics 2024-08-16 Joni Laulainen , Ilkka Helenius , Christian T. Preuss

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 consider the production of a single $Z$ or $W$ boson in association with jets at the LHC. We compute the corresponding cross sections by matching NLO QCD predictions with the Herwig++ and Pythia8 parton showers, and by merging all of the…

High Energy Physics - Phenomenology · Physics 2016-03-23 Rikkert Frederix , Stefano Frixione , Andreas Papaefstathiou , Stefan Prestel , Paolo Torrielli

A procedure is developed for using Soft Collinear Effective Theory (SCET) to generate fully exclusive events, which can then be compared to data from collider experiments. We show that SCET smoothly interpolates between QCD for hard…

High Energy Physics - Phenomenology · Physics 2008-11-26 Christian W. Bauer , Matthew D. Schwartz

The merging procedure of tree-level matrix elements and the subsequent parton shower as implemented in the new event generator SHERPA will be validated for the example of single gauge boson production at the LHC. The validation includes…

High Energy Physics - Phenomenology · Physics 2009-11-11 Frank Krauss , Andreas Schaelicke , Steffen Schumann , Gerhard Soff

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

We present an implementation of the so-called CKKW-L merging scheme for combining multi-jet tree-level matrix elements with parton showers. The implementation uses the transverse-momentum-ordered shower with interleaved multiple…

High Energy Physics - Phenomenology · Physics 2012-03-27 Leif Lonnblad , Stefan Prestel

We study the matching of multijet matrix elements and shower evolution in the case of top production in hadronic collisions at the Tevatron and at the LHC. We present the results of the matching algorithm implemented in the ALPGEN Monte…

High Energy Physics - Phenomenology · Physics 2010-10-27 Michelangelo L. Mangano , Mauro Moretti , Fulvio Piccinini , Michele Treccani

Detailed and precise background predictions are the backbone of large parts of high-energy collider phenomenology. This requires to embed precision QCD calculations into detailed event generators, to produce comprehensive software…

High Energy Physics - Phenomenology · Physics 2022-02-03 Valerio Bertone , Stefan Prestel

We present a study of effects of QCD radiation in the production of heavy colored states, employing inclusive multi-jet samples obtained by matching matrix elements and parton showers. We discuss several examples showing that matched…

High Energy Physics - Phenomenology · Physics 2009-06-09 Johan Alwall , Simon de Visscher , Fabio Maltoni

High Energy Jets provides an all-order description of wide-angle QCD emissions, resumming the leading-logarithmic contributions in the high-energy limit. In this contribution, we briefly summarise the approach and its implementation in a…

High Energy Physics - Phenomenology · Physics 2012-09-20 Jennifer M. Smillie

We develop EventMover, a differentiable parton shower event generator. This tool generates high- and variable-length scattering events that can be moved with simulation derivatives to change the value of the scale $\Lambda_\mathrm{QCD}$…

High Energy Physics - Phenomenology · Physics 2022-08-05 Benjamin Nachman , Stefan Prestel

A main difficulty in understanding the dynamics of jets produced in the high-density environment of ultrarelativistic heavy ion collision, is to provide a unified description for the two sources of radiation that are a priori expected: the…

High Energy Physics - Phenomenology · Physics 2018-12-14 Paul Caucal , Edmond Iancu , Alfred H. Mueller , Gregory Soyez

We review the physics basis, main features and use of general-purpose Monte Carlo event generators for the simulation of proton-proton collisions at the Large Hadron Collider. Topics included are: the generation of hard-scattering matrix…