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Related papers: GenEvA (I): A new framework for event generation

200 papers

We present results for the Higgsstrahlung process within the GENEVA Monte Carlo framework. We combine the fully differential NNLO calculation with the higher-order resummation in the 0-jettiness resolution variable (beam-thrust). The…

High Energy Physics - Phenomenology · Physics 2019-11-27 Simone Alioli , Alessandro Broggio , Stefan Kallweit , Matthew A. Lim , Luca Rottoli

We present a new calculation for the production of isolated photon pairs at the LHC with NNLL$'_{\mathcal{T}_0}$+NNLO accuracy. This is the first implementation within the GENEVA Monte Carlo framework of a process with a nontrivial…

High Energy Physics - Phenomenology · Physics 2021-04-21 Simone Alioli , Alessandro Broggio , Alessandro Gavardi , Stefan Kallweit , Matthew A. Lim , Riccardo Nagar , Davide Napoletano , Luca Rottoli

We present a general method to match fully differential next-to-next-to-leading (NNLO) calculations to parton shower programs. We discuss in detail the perturbative accuracy criteria a complete NNLO+PS matching has to satisfy. Our method is…

High Energy Physics - Phenomenology · Physics 2015-06-17 Simone Alioli , Christian W. Bauer , Calvin Berggren , Frank J. Tackmann , Jonathan R. Walsh , Saba Zuberi

We study the use of higher-order resummation for transverse observables to achieve NNLO+PS matching within the GENEVA framework. In particular, we embed $q_T$ resummation for colour-singlet production at N$^3$LL obtained via soft-collinear…

High Energy Physics - Phenomenology · Physics 2025-05-22 Alessandro Gavardi , Rebecca von Kuk , Matthew A. Lim

We present a process-independent technique to consistently combine next-to-leading order parton-level calculations of varying jet multiplicity and parton showers. Double counting is avoided by means of a modified truncated shower scheme.…

High Energy Physics - Phenomenology · Physics 2015-06-05 Stefan Hoeche , Frank Krauss , Marek Schonherr , Frank Siegert

In recent times the algorithms for the simulation of hadronic collisions have been subject to two substantial improvements: the inclusion, within parton showering, of exact higher order tree level matrix elements (MEPS) and, separately,…

High Energy Physics - Phenomenology · Physics 2015-03-14 Keith Hamilton , Paolo Nason

We apply for the first time the Flow Matching method to the problem of phase-space sampling for event generation in high-energy collider physics. By training the model to remap the random numbers used to generate the momenta and helicities…

High Energy Physics - Phenomenology · Physics 2025-06-25 Enrico Bothmann , Timo Janßen , Max Knobbe , Bernhard Schmitzer , Fabian Sinz

New sets of parameters ("tunes") for the underlying-event (UE) modeling of the PYTHIA8, PYTHIA6 and HERWIG++ Monte Carlo event generators are constructed using different parton distribution functions. Combined fits to CMS UE proton-proton…

High Energy Physics - Experiment · Physics 2016-03-21 CMS Collaboration

We present an algorithm to combine multiple matrix elements at LO and NLO with a parton shower. We build on the unitarized merging paradigm. The inclusion of higher orders and multiplicities reduce the scale uncertainties for observables…

High Energy Physics - Phenomenology · Physics 2018-04-18 Johannes Bellm , Stefan Gieseke , Simon Plätzer

Merging the benefits of an NLO calculation with event generators is a topic of current interest. Among other things, it is advantageous to be able to generate unweighted events according to NLO matrix elements. I report on an algorithm…

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

The Monte Carlo program {\tt WWGENPV}, designed for computing distributions and generating events for four-fermion production in $e^+ e^- $ collisions, is described. The new version, 2.0, includes the full set of the electroweak (EW)…

High Energy Physics - Phenomenology · Physics 2009-10-28 D. G. Charlton , G. Montagna , O. Nicrosini , F. Piccinini

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

The search for new interactions and particles in high-energy collider physics relies on precise background predictions. This has led to many advances in combining precise fixed-order cross-section calculations with detailed event generator…

High Energy Physics - Phenomenology · Physics 2021-11-24 Stefan Prestel

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

In this article we generalise POWHEG next-to-leading order parton shower (NLOPS) simulations of vector boson production and vector boson production in association with a single jet, to give matrix element corrected MENLOPS simulations. In…

High Energy Physics - Phenomenology · Physics 2015-05-30 Simone Alioli , Keith Hamilton , Emanuele Re

We compute the production cross section of a top-antitop pair in association with a jet at hadron colliders at next-to-leading order accuracy matched with parton shower algorithms to make predictions at the hadron level. The parton shower…

High Energy Physics - Phenomenology · Physics 2015-03-17 Adam Kardos , Costas Papadopoulos , Zoltan Trocsanyi

We describe a number of improvements to the GENEVA method for matching NNLO calculations to parton shower programs. In particular, we detail changes to the resummed calculation used in the matching procedure, including disentangling the…

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

With the advent and recent extension of the BLHA standard to interface Monte Carlo event generators and one-loop matrix element providers, the Herwig++ event generator has expanded its range of applicability to a multitude of underlying…

A simple C++ class structure for construction of a Monte Carlo event generators which can produce unweighted events within relativistic phase space is presented. The generator is self-adapting to the provided matrix element and acceptance…

High Energy Physics - Phenomenology · Physics 2018-12-18 R. A. Kycia , J. Chwastowski , R. Staszewski , J. Turnau