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Related papers: Matching Parton Showers and Matrix Elements

200 papers

We consider the associated production of electroweak gauge bosons and charm or beauty quark jets at the LHC using the $k_T$-factorization framework. We apply the transverse momentum dependent (TMD) parton distributions in a proton obtained…

High Energy Physics - Phenomenology · Physics 2020-02-26 A. V. Lipatov , M. A. Malyshev , H. Jung

We present a novel method to combine QCD calculations at next-to-next-to-leading order (NNLO) with parton shower (PS) simulations, that can be applied to the production of heavy systems in hadronic collisions, such as colour singlets or a…

High Energy Physics - Phenomenology · Physics 2022-01-11 Pier Francesco Monni , Paolo Nason , Emanuele Re , Marius Wiesemann , Giulia Zanderighi

We present theoretical predictions for the hadroproduction of t tbar W+, t tbar W- and t tbar Z at LHC as obtained by matching numerical computations at NLO accuracy in QCD with Shower Monte Carlo programs. The calculation is performed by…

High Energy Physics - Phenomenology · Physics 2012-12-03 M. V. Garzelli , A. Kardos , C. G. Papadopoulos , Z. Trócsányi

We study factorization schemes for parton shower models in hadron-hadron collisions. As an example, we calculate lepton pair production mediated by a virtual photon in quark--anti-quark annihilation, and we compare factorized cross sections…

High Energy Physics - Phenomenology · Physics 2008-11-26 Hidekazu Tanaka , Yu Matsuda , Hirokazu Kobayashi

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

This is the user's manual of MC@NLO 3.4. This package is a practical implementation, based upon the HERWIG event generator, of the MC@NLO formalism, which allows one to incorporate NLO QCD matrix elements consistently into a parton shower…

High Energy Physics - Phenomenology · Physics 2008-12-04 Stefano Frixione , Bryan R. Webber

Comparisons of experimental data with theoretical predictions for collider processes containing hadronic jets rely on shower Monte Carlo event generators to include corrections to perturbative calculations from hadronization, parton…

High Energy Physics - Phenomenology · Physics 2013-05-15 S. Dooling , P. Gunnellini , F. Hautmann , H. Jung

We discuss the theoretical bases that underpin the automation of the computations of tree-level and next-to-leading order cross sections, of their matching to parton shower simulations, and of the merging of matched samples that differ by…

High Energy Physics - Phenomenology · Physics 2015-06-19 J. Alwall , R. Frederix , S. Frixione , V. Hirschi , F. Maltoni , O. Mattelaer , H. -S. Shao , T. Stelzer , P. Torrielli , M. Zaro

To explore the interplay of NLO matching and next-to-leading logarithmic (NLL) parton showers, we consider the simplest case of $\gamma^*$ and Higgs-boson decays to $q\bar q$ and $gg$ respectively. Not only should shower NLL accuracy be…

High Energy Physics - Phenomenology · Physics 2023-10-25 Keith Hamilton , Alexander Karlberg , Gavin P. Salam , Ludovic Scyboz , Rob Verheyen

We present a full-fledged antenna shower for hadron collisions in the Vincia framework and focus on initial state radiation. The current version of the shower is limited to massless QCD partons and colourless resonances. As a…

High Energy Physics - Phenomenology · Physics 2016-04-20 Nadine Fischer , Peter Skands

We investigate the effects of keeping the full color structure for parton emissions in parton showers for both LEP and LHC. This is done within the Herwig 7 dipole shower, and includes gluon emission, gluon splitting, initial state…

High Energy Physics - Phenomenology · Physics 2018-11-14 Simon Plätzer , Malin Sjodahl , Johan Thorén

We are developing a consistent method to combine tree-level event generators for hadron collision interactions with those including one additional QCD radiation from the initial-state partons, based on the limited leading-log (LLL)…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. Odaka , Y. Kurihara

We estimate possible systematic error that can arise in the simplified simulation of the $W_R$ production and its subsequent decay into heavy neutrino at LHC (left-right symmetric model). The general-purpose event generators simulate this…

High Energy Physics - Phenomenology · Physics 2011-12-01 G. Bednik , M. Kirsanov

The hadroproduction of a $W$ boson in association with a charm quark at the Large Hadron Collider is at the centre of current investigations due to its potential to probe the strangeness content of the proton. In this paper we present an…

High Energy Physics - Phenomenology · Physics 2022-04-27 G. Bevilacqua , M. V. Garzelli , A. Kardos , L. Toth

We report on a high-precision calculation of the Bhabha process in QED, of interest for precise luminosity determination of low-energy electron-positron colliders. The calculation is based on the matching of exact next-to-leading order…

High Energy Physics - Phenomenology · Physics 2007-05-23 G. Balossini , C. M. Carloni Calame , G. Montagna , O. Nicrosini , F. Piccinini

The matrix element method is the LHC inference method of choice for limited statistics. We present a dedicated machine learning framework, based on efficient phase-space integration, a learned acceptance and transfer function. It is based…

High Energy Physics - Phenomenology · Physics 2024-11-13 Theo Heimel , Nathan Huetsch , Ramon Winterhalder , Tilman Plehn , Anja Butter

We derive a new method for initial-state collinear showering in Monte-Carlo event generators which is based on the use of unintegrated parton correlation functions. Combined with a previously derived method for final-state showering, the…

High Energy Physics - Phenomenology · Physics 2008-11-26 John C. Collins , Xiaomin Zu

We consider the probability for a colour-singlet qqbar pair to emit a gluon, in strongly and smoothly ordered antenna showers. We expand to second order in alphaS and compare to the second-order QCD matrix elements for Z -> 3 jets,…

High Energy Physics - Phenomenology · Physics 2016-10-04 L. Hartgring , E. Laenen , P. Skands

We improve the theoretical predictions for the production of extra neutral gauge bosons at hadron colliders by implementing the Z' bosons in the MC@NLO generator and by computing their differential and total cross sections in joint p_T and…

High Energy Physics - Phenomenology · Physics 2008-11-26 B. Fuks , M. Klasen , F. Ledroit , Q. Li , J. Morel

We calculate the process $pp\to W^+W^-\to e^+ \nu_e \mu^-\bar{\nu}_\mu$ at NLO QCD, including also effective field theory (EFT) operators mediating the $ggW^+W^-$ interaction, which first occur at dimension eight. We further combine the NLO…