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Related papers: QCD Matrix Elements + Parton Showers

200 papers

In this short note, I introduce to essential conceptual features and main building blocks of matrix element merging algorithms, operating on fixed order calculations both at leading order and next-to-leading order. The intention is purely…

High Energy Physics - Phenomenology · Physics 2015-03-30 Thomas Rössler

I discuss the calculation of QCD jet rates in e+e- annihilation as a testing ground for parton shower simulations and jet finding algorithms.

High Energy Physics - Phenomenology · Physics 2017-08-23 Bryan R. Webber

We present an algorithm to evaluate the exact, tree-level matrix elements for multi-parton processes in QCD. We tested this technique, based on the recursive evaluation of the S-matrix, on processes such as gg -> n gluons and q qbar -> n…

High Energy Physics - Phenomenology · Physics 2009-07-09 F. Caravaglios , M. L. Mangano , M. Moretti , R. Pittau

We present a method to match the multi-parton states generated by the High Energy Jets Monte Carlo with parton showers generated by the Ariadne program using the colour dipole model. The High Energy Jets program already includes a full…

High Energy Physics - Phenomenology · Physics 2015-03-19 Jeppe R. Andersen , Leif Lonnblad , Jennifer M. Smillie

Recent developments in QCD phenomenology have spurred on several improved approaches to Monte Carlo event generation, relative to the post--LEP state of the art. In this brief review, the emphasis is placed on approaches for 1) consistently…

High Energy Physics - Phenomenology · Physics 2009-11-11 Peter Z. Skands

We present a method to combine next-to-leading order (NLO) matrix elements in QCD with leading logarithmic parton showers by applying a suitably modified version of the phase-space-slicing method. The method consists of subsuming the NLO…

High Energy Physics - Phenomenology · Physics 2009-10-31 B. Pötter

In this talk the newly developped Monte-Carlo event generator {\tt APACIC++} suitable to describe multijet-events in high-energetic electron-positron annihilations is presented. A new ansatz to match the corresponding matrix elements for…

High Energy Physics - Phenomenology · Physics 2014-11-17 F. Krauss , R. Kuhn , G. Soff

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 present a new formulation of jet quenching in perturbative QCD beyond the eikonal approximation. Multiple scattering in the medium is modelled through infra-red-continued (2 -> 2) scattering matrix elements in QCD and the parton shower…

High Energy Physics - Phenomenology · Physics 2012-04-03 Korinna C. Zapp , Frank Krauss , Urs A. Wiedemann

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

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

This paper presents the method of combining parton shower formalism with perturbative calculations (matrix elements) in form of a Monte-Carlo algorithm for the process g g -> Z b anti-b,consistenlty including the heavy quark masses and…

High Energy Physics - Phenomenology · Physics 2008-11-26 B. P. Kersevan , I. Hinchliffe , L. Mijovic

We investigate parton-branching methods based on transverse-momentum dependent (TMD) parton distributions and matrix elements for the Monte Carlo simulation of multi-particle final states at high-energy colliders. We observe that recently…

High Energy Physics - Phenomenology · Physics 2008-11-26 F. Hautmann , H. Jung

A method for incorporating information from next-to-leading order QCD matrix elements for hadronic diboson production into showering event generators is presented. In the hard central region (high jet transverse momentum) where perturbative…

High Energy Physics - Phenomenology · Physics 2009-11-07 Matt Dobbs

We propose a general approach for the description of multijet events in the framework of QCD event generators. We introduce a new algorithm to match parton showers and arbitrary matrix elements for the production of any number of jets via…

High Energy Physics - Phenomenology · Physics 2009-10-31 F. Krauss , R. Kuhn , G. Soff

We study in this paper the production, in hadronic collisions, of final states with W gauge bosons, heavy quark pairs and n extra jets (with n up to 4). The complete partonic tree-level QCD matrix elements are evaluated using the ALPHA…

High Energy Physics - Phenomenology · Physics 2008-11-26 Michelangelo L. Mangano , Mauro Moretti , Roberto Pittau

We present a Monte-Carlo approach to prompt-photon production, where photons and QCD partons are treated democratically. The photon fragmentation function is modelled by an interleaved QCD+QED parton shower. This known technique is improved…

High Energy Physics - Phenomenology · Physics 2014-11-20 Stefan Hoeche , Steffen Schumann , Frank Siegert

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

We illustrate a study based on a veto technique to match parton showers and matrix elements in the Cascade Monte Carlo event generator, and present a numerical application to gluon matrix elements for jet production.

High Energy Physics - Phenomenology · Physics 2012-06-11 Michal Deak , Francesco Hautmann , Hannes Jung , Krzysztof Kutak

Jet quenching - the modification of high-energy jets in the quark-gluon plasma - has been extensively studied through weakly coupled scattering amplitudes embedded in parton-shower frameworks. These models, often combined with bulk…

High Energy Physics - Phenomenology · Physics 2026-04-10 Ismail Soudi , Adam Takacs