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Related papers: The Vincia Parton Shower

200 papers

We formulate PanScales parton showers for hadron collisions so as to achieve next-to-leading logarithmic (NLL) accuracy across a broad set of observables. We do so specifically for colour singlet production. Relative to the existing…

High Energy Physics - Phenomenology · Physics 2022-11-23 Melissa van Beekveld , Silvia Ferrario Ravasio , Gavin P. Salam , Alba Soto-Ontoso , Gregory Soyez , Rob Verheyen

We present the first public implementation of antenna-based QCD initial- and final-state showers. The shower kernels are $2\to 3$ antenna functions, which capture not only the collinear dynamics but also the leading soft (coherent)…

High Energy Physics - Phenomenology · Physics 2016-11-23 Nadine Fischer , Stefan Prestel , Mathias Ritzmann , Peter Skands

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…

We apply Laplace method for the tree diagrams to calculate the interference terms arising as a result of summation of particles permutations in the final state of scattering. These terms significantly influence the values of experimentally…

High Energy Physics - Phenomenology · Physics 2021-12-02 O. S. Potiienko , I. V. Sharph , N. O. Chudak , D. S. Domin , I. O. Shelkovenko , K. K. Merkotan

Parton showers are crucial components of high-energy physics calculations. Improving their modelling of QCD is an active research area since shower approximations are stumbling blocks for precision event generators. Naively, the…

High Energy Physics - Phenomenology · Physics 2022-09-13 Leif Gellersen , Stefan Prestel , Michael Spannowsky

We discuss two ways in which parton shower algorithms can be supplemented by matrix-element corrections to ensure the correct hard limit: by using complementary phase-space regions, or by modifying the shower itself. In the former case,…

High Energy Physics - Phenomenology · Physics 2010-04-06 Michael H. Seymour

We describe an algorithm for improving subsequent parton shower emissions by full SU(3) color correlations in the framework of a dipole-type shower. As a proof of concept, we present results from the first implementation of such an…

High Energy Physics - Phenomenology · Physics 2015-06-03 Simon Platzer , Malin Sjodahl

We introduce a technique for the next-to-leading order accurate simulation of $e^+e^-\to W^+W^-b\bar{b}$ that respects the resonant nature of the process above and near the top-quark pair production threshold. The parton-shower evolution,…

High Energy Physics - Phenomenology · Physics 2026-04-16 Stefan Höche , Daniel Reichelt

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

In this study we tried to emphasize the role parton shower plays in event generation, and in the physics of high energy event generation. We achieved this task by comparing the next-to-leading order and next-to-next-to-leading order results…

High Energy Physics - Phenomenology · Physics 2014-05-08 Hessamoddin Kaveh , Mohammad Ebrahim Zomorrodian

We present algorithms that interleave photon radiation from the final state and the initial state with the QCD evolution in the antenna-based Vincia parton shower. One of the algorithms incorporates the complete soft and collinear structure…

High Energy Physics - Phenomenology · Physics 2020-10-28 Peter Skands , Rob Verheyen

We investigate the effects of combining next-to-leading order QCD results with parton-shower effects in $W^+W^-jj$ production via vector-boson fusion including leptonic decays. Using the Herwig 7 framework interfaced to VBFNLO 3, we compare…

High Energy Physics - Phenomenology · Physics 2016-07-04 Michael Rauch , Simon Plätzer

We present a new formalism for parton shower simulation of QCD jets, which incorporates the following features: invariance under boosts along jet axes, improved treatment of heavy quark fragmentation, angular-ordered evolution with soft…

High Energy Physics - Phenomenology · Physics 2014-11-17 Stefan Gieseke , Philip Stephens , Bryan Webber

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 propose to model hadronization of parton showers in QCD jets through a hybrid approach involving quark recombination and string fragmentation. This is achieved by allowing gluons at the end of the perturbative shower evolution to undergo…

Nuclear Theory · Physics 2016-04-20 Kyong Chol Han , Rainer J. Fries , Che Ming Ko

We extend the lowest-order matching of tree-level matrix elements with parton showers to give a complete description at the next higher perturbative accuracy in alpha_s at both small and large jet resolutions, which has not been achieved so…

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

We present an antenna shower formalism including contributions from initial-state partons and corresponding backwards evolution. We give a set of phase-space maps and antenna functions for massless partons which define a complete shower…

High Energy Physics - Phenomenology · Physics 2015-06-11 M. Ritzmann , D. A. Kosower , P. Skands

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

The Pythia event generator is used in several contexts to study hadron and lepton interactions, notably $pp$ and $p\bar{p}$ collisions. In this article we extend the hadronic modelling to encompass the collision of a wide range of hadrons…

High Energy Physics - Phenomenology · Physics 2022-01-26 Torbjörn Sjöstrand , Marius Utheim