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Related papers: Initial State Parton Showers Beyond Leading Order

200 papers

We show that the presence of an infrared cutoff $Q_0$ in the parton shower (PS) evolution for massive quarks implies that the generator quark mass corresponds to a $Q_0$-dependent short-distance mass scheme and is therefore not the pole…

High Energy Physics - Phenomenology · Physics 2018-11-14 André H. Hoang , Simon Plätzer , Daniel Samitz

We propose a new subtraction scheme for next-to-leading order QCD calculations. Our scheme is based on the momentum mapping and on the splitting functions derived in the context of an improved parton shower formulation. Compared to standard…

High Energy Physics - Phenomenology · Physics 2015-05-20 Cheng-Han Chung , Michael Krämer , Tania Robens

By considering clans as genuine elementary subprocesses, i.e., intermediate parton sources in the Simplified Parton Shower model, a generalized version of this model is defined. It predicts analytically clan properties at parton level in…

High Energy Physics - Phenomenology · Physics 2009-09-25 R. Ugoccioni , A. Giovannini , S. Lupia

We report on a method for matching the next-to-leading order calculation of QCD jet production in e+e- annihilation with a Monte Carlo parton shower event generator (MC) to produce realistic final states. The final result is accurate to…

High Energy Physics - Phenomenology · Physics 2008-11-26 Michael Krämer , Stephen Mrenna , Davison E. Soper

We present hadron-level predictions from the Monte Carlo generator Cascade and numerical level calculations of beauty quark and inclusive b-jet production in the framework of the kT -factorization QCD approach for CERN LHC energies. The…

High Energy Physics - Phenomenology · Physics 2015-03-19 H. Jung , M. Kraemer , A. V. Lipatov , N. P. Zotov

We present hadron-level predictions from the Monte Carlo generator Cascade and numerical calculations of charm and beauty production at the Fermilab Tevatron within the framework of the $k_T$-factorization QCD approach. Our consideration is…

High Energy Physics - Phenomenology · Physics 2011-01-25 H. Jung , M. Kraemer , A. V. Lipatov , N. P. Zotov

Spin correlations are an important, but often neglected, effect in modern Monte Carlo event generators. We show that they can be fully incorporated in Herwig 7 using the algorithm originally proposed by Collins and Knowles in all stages of…

High Energy Physics - Phenomenology · Physics 2018-07-06 Peter Richardson , Stephen Webster

Evaluating parton density systematic uncertainties in Monte~Carlo event generator predictions has long been achieved by reweighting between the original and systematic PDFs for the initial state configurations of the individual simulated…

High Energy Physics - Phenomenology · Physics 2016-03-08 Andy Buckley

We address the problem of decomposing graphs in perturbative QCD into terms associated with particular regions. Motivated by asking how to incorporate next-to-leading order (NLO) QCD corrections in parton-shower algorithms, we require that:…

High Energy Physics - Phenomenology · Physics 2010-02-03 J. C. Collins , F. Hautmann

Parton showers have become a standard component in the description of high-energy collisions. Nowadays most final-state ones are of the dipole character, wherein a pair of partons branches into three, with energy and momentum preserved…

High Energy Physics - Phenomenology · Physics 2018-04-18 Baptiste Cabouat , Torbjörn Sjöstrand

Parton shower algorithms are key components of theoretical predictions for high-energy collider physics. Work towards more accurate parton shower algorithms is thus pursued along many different avenues. The systematic treatment of…

High Energy Physics - Phenomenology · Physics 2019-01-23 Joshua Isaacson , Stefan Prestel

Monte Carlo event generators are in a modern terminology the digital twins of collider-based particle physics experiment. We give an introduction into the application of MC generators for particle physics, discuss their different components…

High Energy Physics - Phenomenology · Physics 2025-09-29 Jürgen Reuter

We present a parton-shower matched NNLO QCD calculation for hadronic final state production in Deep Inelastic Scattering. The computation is based on the UNLOPS method and is implemented in the publicly available event generation framework…

High Energy Physics - Phenomenology · Physics 2018-12-19 Stefan Höche , Silvan Kuttimalai , Ye Li

In this contribution, we will give a brief overview of the progress that has been achieved in the field of combining matrix elements and parton showers. We exemplify this by focusing on the case of electron--positron collisions and by…

High Energy Physics - Phenomenology · Physics 2012-04-26 Jan Winter , Stefan Hoeche , Hendrik Hoeth , Frank Krauss , Marek Schonherr , Steffen Schumann , Frank Siegert , Korinna Zapp

We derive an improved prescription for the merging of matrix elements with parton showers, extending the CKKW approach. A flavour-dependent phase space separation criterion is proposed. We show that this new method preserves the logarithmic…

High Energy Physics - Phenomenology · Physics 2010-03-05 Stefan Hoeche , Frank Krauss , Steffen Schumann , Frank Siegert

We discuss coherent QCD radiation from space-like parton branching and its effects on multi-jet final states at high-energy hadron colliders. Coherence effects for small longitudinal momentum fractions x are not included in the branching…

High Energy Physics - Phenomenology · Physics 2009-11-13 F. Hautmann , H. Jung

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

A main difficulty in understanding the dynamics of jets produced in the high-density environment of ultrarelativistic heavy ion collision, is to provide a unified description for the two sources of radiation that are a priori expected: the…

High Energy Physics - Phenomenology · Physics 2018-12-14 Paul Caucal , Edmond Iancu , Alfred H. Mueller , Gregory Soyez

Modern parton showers are built using one of two models: dipole showers or angular ordered showers. Both have distinct strengths and weaknesses. Dipole showers correctly account for wide-angle, soft gluon emissions and track the leading…

High Energy Physics - Phenomenology · Physics 2020-09-02 Jeffrey R. Forshaw , Jack Holguin , Simon Plätzer

We report on the implementation of an interface between the SANC generator framework for Drell-Yan hard processes, which includes next-to-leading order electroweak (NLO EW) corrections, and the Herwig++ and Pythia8 QCD parton shower Monte…

High Energy Physics - Phenomenology · Physics 2015-05-20 P. Richardson , R. R. Sadykov , A. A. Sapronov , M. H. Seymour , P. Z. Skands