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Related papers: Initial State Parton Showers Beyond Leading Order

200 papers

Parton shower evolution is given by a renormalization group equation that reflects the infrared behavior of perturbative QCD including color and spin and including quantum interference. With added approximations, such an evolution equation…

High Energy Physics - Phenomenology · Physics 2026-05-13 Zoltan Nagy , Davison E. Soper

We carry out a systematic classification and computation of next-to-leading order kinematic power corrections to the fully differential cross section in the parton shower. To do this we devise a map between ingredients in a parton shower…

High Energy Physics - Phenomenology · Physics 2011-02-18 Matthew Baumgart , Claudio Marcantonini , Iain W. Stewart

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

The possibility of an improvement of current NLO Monte Carlo event generators by means of choosing a suitable factorization scheme is studied. The optimal factorization scheme for combining initial state parton showers and NLO hard…

High Energy Physics - Phenomenology · Physics 2012-12-12 Karel Kolar

We present an implementation of a parton shower algorithm for hadron colliders and electron-positron colliders based on the dipole factorisation formulae. The algorithm treats initial-state partons on equal footing with final-state partons.…

High Energy Physics - Phenomenology · Physics 2008-11-26 Michael Dinsdale , Marko Ternick , Stefan Weinzierl

The concept of new methodology of adding QCD NLO corrections in the initial state Monte Carlo parton shower (hard process part) is tested numerically using, as an example, the process of the heavy boson production at hadron--hadron…

High Energy Physics - Phenomenology · Physics 2013-01-03 S. Jadach , M. Jezabek , A. Kusina , W. Placzek , M. Skrzypek

We investigate angular correlations in multi-jet final states at high-energy colliders and discuss their sensitivity to initial-state showering effects, including QCD coherence and corrections to collinear ordering.

High Energy Physics - Phenomenology · Physics 2008-08-27 F. Hautmann , H. Jung

Substantial progress has been made recently in the formalisms which form the basis of event generators. I discuss some of the ideas involved, emphasizing the role of higher-order QCD corrections and their interplay with parton showers

High Energy Physics - Phenomenology · Physics 2007-05-23 Stefano Frixione

Motivated by the need to correct the potentially large kinematic errors in approximations used in the standard formulation of perturbative QCD, we reformulate deeply inelastic lepton-proton scattering in terms of gauge invariant, universal…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. C. Collins , T. C. Rogers , A. M. Staśto

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

I report on a formalism introduced recently to combine parton shower Monte Carlo's and next-to-leading order QCD computations.

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Frixione

We present a parton shower which implements the DGLAP evolution of parton densities and fragmentation functions at next-to-leading order precision up to effects stemming from local four-momentum conservation. The Monte-Carlo simulation is…

High Energy Physics - Phenomenology · Physics 2017-11-01 Stefan Höche , Frank Krauss , Stefan Prestel

In this thesis, we present automated, process-independent methods for the calculation of QED real radiative corrections. We review the construction of a parton shower based on Catani-Seymour dipole subtraction, and thus detail the…

High Energy Physics - Phenomenology · Physics 2024-09-05 Lois Flower

The use of QCD calculations that include the resummation of soft-collinear logarithms via parton-shower algorithms is currently not possible in PDF fits due to the high computational cost of evaluating observables for each variation of the…

High Energy Physics - Phenomenology · Physics 2019-01-30 Enrico Bothmann , Luigi Del Debbio

Coherent QCD radiation in the hadroproduction of top quark pairs leads to a forward--backward asymmetry that grows more negative with increasing transverse momentum of the pair. This feature is present in Monte Carlo event generators with…

High Energy Physics - Phenomenology · Physics 2012-09-24 Peter Z. Skands , Bryan R. Webber , Jan Winter

We present a new approach to combine multiple NLO parton-level calculations matched to parton showers into a single inclusive event sample. The method provides a description of hard multi-jet configurations at next-to leading order in the…

High Energy Physics - Phenomenology · Physics 2013-02-14 Thomas Gehrmann , Stefan Hoeche , Frank Krauss , Marek Schonherr , Frank Siegert

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 have previously described a mathematical formulation for a parton shower based on the approximation of strongly ordered virtualities of successive parton splittings. Quantum interference, including interference among different color and…

High Energy Physics - Phenomenology · Physics 2009-04-30 Zoltan Nagy , Davison E. Soper

Parton showers lie at the core of Shower Monte Carlo event generators, the default theoretical tools used to interpret collider data. In these proceedings, we summarise the strategy of the PanScales collaboration that led to the attainment…

High Energy Physics - Phenomenology · Physics 2025-05-20 Silvia Ferrario Ravasio

We review the methods developed for combining the parton shower approximation to QCD with fixed-order perturbation theory, in such a way as to achieve next-to-leading-order (NLO) accuracy for inclusive observables. This has made it possible…

High Energy Physics - Phenomenology · Physics 2015-06-04 Paolo Nason , Bryan Webber