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Related papers: Towards NNLO+PS Matching with Sector Showers

200 papers

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…

Higher order calculations are necessary to predict and describe measurements in high energy collider physics. In recent years multiple approaches to combine multiple next-to-leading (NLO) order corrections with parton showers had been…

High Energy Physics - Phenomenology · Physics 2016-07-08 Johannes Bellm

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 report on a major milestone in the construction of logarithmically accurate final-state parton showers, achieving next-to-next-to-leading-logarithmic (NNLL) accuracy for the wide class of observables known as event shapes. The key to…

We propose a new method of computing real emission contributions to hard QCD processes. Our approach uses sector decomposition of the exclusive final-state phase space to enable extraction of all singularities of the real emission matrix…

High Energy Physics - Phenomenology · Physics 2008-11-26 C. Anastasiou , Kirill Melnikov , Frank Petriello

We present methods to achieve NLL+NLO accurate parton showering for processes with two coloured legs: neutral- and charged-current Drell-Yan, and Higgs production in $pp$ collisions, as well as DIS and $e^+e^-$ to jets. The methods include…

We summarize recent developments in the VINCIA parton shower. After a brief review of the basics of the formalism, the extension of VINCIA to hadron collisions is sketched. We then turn to improvements of the efficiency of tree-level…

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

We present a new approach to coherent parton showers in the decays of coloured resonances, based on the notion of "resonance-final" (RF) QCD antennae. A full set of mass- and helicity-dependent $2\to 3$ antenna functions are defined, with…

High Energy Physics - Phenomenology · Physics 2020-02-06 Helen Brooks , Peter Skands

We here present an extension of the CKKW-L multi-jet merging technique to so-called sector showers as implemented in the Vincia antenna shower. The bijective nature of sector showers allows for efficient multi-jet merging at high…

High Energy Physics - Phenomenology · Physics 2021-05-03 Helen Brooks , Christian T Preuss

General-purpose Monte Carlo event generators have become important tools in particle physics, allowing the simulation of exclusive hadronic final states. In this article we examine the Pythia 8 generator, in particular focusing on its…

High Energy Physics - Phenomenology · Physics 2011-03-18 Richard Corke , Torbjörn Sjöstrand

We compare a NLO W gamma matrix element generator with the leading order calculation in Pythia . A matching scheme between a next-to-leading order W gamma matrix element generator by Baur et. al. and the Pythia parton shower is presented.…

High Energy Physics - Phenomenology · Physics 2010-02-24 D. Majumder , K. Mazumdar , T. Sjostrand

The decade-old technique of combining NLO-corrected hard process with LO-level parton shower Monte Carlo is now mature and used in practice of the QCD calculations in the LHC data analysis. The next step, its extension to an NNLO-corrected…

High Energy Physics - Phenomenology · Physics 2015-06-17 S. Jadach , A. Kusina , W. Placzek , M. Skrzypek

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

We formulate a collinear partonic shower algorithm that achieves next-to-single-logarithmic (NSL, $\alpha_s^n L^{n-1}$) accuracy for collinear-sensitive non-singlet fragmentation observables. This entails the development of an algorithm for…

High Energy Physics - Phenomenology · Physics 2024-09-16 Melissa van Beekveld , Mrinal Dasgupta , Basem Kamal El-Menoufi , Jack Helliwell , Pier Francesco Monni , Gavin P. Salam

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

A new method for combining QCD matrix elements and parton showers in Monte Carlo simulations of hadronic final states is outlined. The aim is to provide at least a leading-order description of all hard multi-jet configurations together with…

High Energy Physics - Phenomenology · Physics 2007-05-23 B. R. Webber

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 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

We propose a new approach for combining next-to-leading order (NLO) and parton shower (PS) calculations so as to obtain three core features: (a) applicability to general showers, as with the MCatNLO and POWHEG methods; (b) positive-weight…

High Energy Physics - Phenomenology · Physics 2022-02-02 Paolo Nason , Gavin P. Salam