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Related papers: Parton-shower effects in polarized deep inelastic …

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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

The phenomenon of scaling in deep inelastic lepton-nucleon scattering is usually explained in terms of the Feynman parton model, and the logarithmic corrections to scaling are explained in the framework of perturbative QCD. For testing the…

High Energy Physics - Phenomenology · Physics 2016-09-01 Felix. M. Lev

In this talk, I show the automated Monte Carlo simulations at next-to-leading order in QCD as well as its matching to parton showers are already feasible within the framework of \MG5aMC. I briefly overview the recent activities and take the…

High Energy Physics - Phenomenology · Physics 2017-08-02 Hua-Sheng Shao

We introduce a method for the separation of soft and collinear logarithms in QCD parton evolution at $\mathcal{O}(\alpha_s^2)$ and at leading color. Using an implementation of the technique in the Dire parton shower, we analyze the…

High Energy Physics - Phenomenology · Physics 2022-06-29 Leif Gellersen , Stefan Höche , Stefan Prestel

Experimental measurements of angular correlations in three-jet final states have recently been performed in DIS. Next-to-leading-order QCD results for these observables are affected by large theoretical uncertainties in the kinematic region…

High Energy Physics - Phenomenology · Physics 2008-04-11 F. Hautmann , H. Jung

We evaluate the theoretical uncertainties in next-to-leading order plus parton shower predictions for top quark pair production and decay in hadronic collisions. Our work is carried out using the Herwig 7 event generator and presents an…

High Energy Physics - Phenomenology · Physics 2020-01-08 Kyle Cormier , Simon Plätzer , Christian Reuschle , Peter Richardson , Stephen Webster

We present a study of effects of QCD radiation in the production of heavy colored states, employing inclusive multi-jet samples obtained by matching matrix elements and parton showers. We discuss several examples showing that matched…

High Energy Physics - Phenomenology · Physics 2009-06-09 Johan Alwall , Simon de Visscher , Fabio Maltoni

With the recently emerging global interest in building a next generation of circular electron-positron colliders to study the properties of the Higgs boson, and other important topics in particle physics at ultra-high beam energies, it is…

Accelerator Physics · Physics 2015-05-25 Zhe Duan , Mei Bai , Desmond P. Barber , Qing Qin

We investigate positron scattering upon endohedrals and compare it with electron-endohedral scattering. We show that the polarization of the fullerene shell considerably alters the polarization potential of an atom, stuffed inside a…

Atomic Physics · Physics 2017-08-02 M. Ya. Amusia , L. V. Chernysheva

First, we present a combined analysis of ${\rm p}{\rm p} \to \mu^+ \nu_\mu {\rm e}^- \bar \nu_{\rm e}$ and ${\rm p}{\rm p} \to \mu^+ \nu_\mu {\rm e}^- \bar \nu_{\rm e} {\rm j}$ at next-to-leading order, including both QCD and electroweak…

High Energy Physics - Phenomenology · Physics 2020-12-02 Stephan Bräuer , Ansgar Denner , Mathieu Pellen , Marek Schönherr , Steffen Schumann

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

POLDIS is a Monte Carlo program for polarized (semi-inclusive) deep inelastic scattering (DIS). Unpolarized DIS events are generated with the existing lepto-production event generators LEPTO for DIS and AROMA for Heavy Flavor production.…

High Energy Physics - Phenomenology · Physics 2009-10-30 Alessandro Bravar , Krzysztof Kurek , Roland Windmolders

A new model of QCD parton shower is proposed which is dedicated to two-photon process in $e^+ e^-$ scattering. When hadron jets are produced, the photon may resolve into quark-antiquark pairs so that the structure functions of the photon…

High Energy Physics - Phenomenology · Physics 2014-11-17 T. Munehisa , P. Aurenche , J. -Ph. Guillet , M. Fontannaz , Y. Shimizu

A recent global analysis of direct photon production at hadron collider and fixed target experiments has noted a disturbing trend of disagreement between next-to-leading-order (NLO) calculations and data. The conjecture has been made that…

High Energy Physics - Phenomenology · Physics 2009-10-28 Howard Baer , Mary Hall Reno

We study the mismatch between a full calculation of non-global single-logarithms in the large-N_c limit and an approximation based on free azimuthal averaging, and the consequent angular-ordered pattern of soft gluon radiation in QCD. We…

High Energy Physics - Phenomenology · Physics 2010-10-27 Andrea Banfi , Gennaro Corcella , Mrinal Dasgupta

A previous calculation of electroweak O(alpha) corrections to deep-inelastic neutrino scattering, as e.g. measured by NuTeV and NOMAD, is supplemented by higher-order effects. In detail, we take into account universal two-loop effects from…

High Energy Physics - Phenomenology · Physics 2009-11-11 K. -P. O. Diener , S. Dittmaier , W. Hollik

Multiple parton interactions are typically implemented in Montecarlo codes by assuming a Poissonian distribution of collisions with average number depending on the impact parameter. A possible generalization, which links the process to…

High Energy Physics - Phenomenology · Physics 2008-08-21 Daniele Treleani

We extend the previously developed small $x$ parton shower algorithm to include the kinematic constraint effect and $k_t$ resummation effect. This work enables the Monte Carlo generator to simultaneously resum large $k_t$ and small $x$…

High Energy Physics - Phenomenology · Physics 2023-07-11 Yu Shi , Shu-Yi Wei , Jian Zhou

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

Recent progress in calculating lepton density functions inside the proton and simulating lepton showers laid the foundations for precision studies of resonant leptoquark production at hadron colliders. Direct quark-lepton fusion into a…

High Energy Physics - Phenomenology · Physics 2022-12-14 Luca Buonocore , Admir Greljo , Peter Krack , Paolo Nason , Nudzeim Selimovic , Francesco Tramontano , Giulia Zanderighi