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Related papers: Implementing NLO DGLAP evolution in Parton Showers

200 papers

We summarize recent results on the evolution of unpolarized parton densities and deep-inelastic structure functions in massless perturbative QCD. Due to last year's extension of the integer-moment calculations of the three-loop splitting…

High Energy Physics - Phenomenology · Physics 2008-11-26 W. L. van Neerven , A. Vogt

We present a method for obtaining an initial-state parton shower model where the (backward) evolution fully consistent with the (forward) evolution of the collinear parton density used. As a proof-of-concept we use parton densities obtained…

High Energy Physics - Phenomenology · Physics 2025-04-15 H. Jung , L. Lönnblad , M. Mendizabal , S. Taheri Monfared

Numerical solution of DGLAP $Q^2$ evolution equations is studied for polarized parton distributions by using a ``brute-force" method. NLO contributions to splitting functions are recently calculated,and they are included in our analysis.…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Hirai , S. Kumano , M. Miyama

We present a phenomenological study of the current status of the application of our approach of {\it exact} amplitude-based resummation in quantum field theory to precision QCD calculations, by realistic MC event generator methods, as…

High Energy Physics - Phenomenology · Physics 2014-09-22 S. K. Majhi , A. Mukhopadhyay , B. F. L. Ward , S. A. Yost

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 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…

In the case of the gluon-fusion process in deep-inelastic leptoproduction, I explicitly show how to incorporate NLO corrections in a Monte-Carlo event generator by a subtraction method. I calculate the parton densities to be used by the…

High Energy Physics - Phenomenology · Physics 2009-10-31 John Collins

Programs that calculate observables in quantum chromodynamics at next-to-leading order typically suffer from the problem that, when considered as event generators, the events generated consist of partons rather than hadrons and just a few…

High Energy Physics - Phenomenology · Physics 2009-04-13 Michael Kramer , Davison E. Soper

Next steps in development of the KrkNLO method of implementing NLO QCD corrections to hard processes in parton shower Monte Carlo programs are presented. This new method is a simpler alternative to other well-known approaches, such as…

High Energy Physics - Phenomenology · Physics 2016-08-10 S. Jadach , W. Placzek , S. Sapeta , A. Siodmok , M. Skrzypek

The connection between analytic and Monte Carlo calculations of soft gluon emission is reanalyzed in light of recent, theoretical developments in resummation. An alternative Monte Carlo algorithm is suggested which incorporates (1)…

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

We perform a detailed study of NLO parton shower matching uncertainties in Higgs boson pair production through gluon fusion at the LHC based on a generic and process independent implementation of NLO subtraction and parton shower matching…

High Energy Physics - Phenomenology · Physics 2018-04-04 Stephen Jones , Silvan Kuttimalai

While experimental studies on jet quenching have achieved a large sophistication, the theoretical description of this phenomenon still misses some important points. One of them is the interplay of vacuum-like emissions, usually formulated…

High Energy Physics - Phenomenology · Physics 2023-07-18 Carlota Andrés , Liliana Apolinário , Néstor Armesto , André Cordeiro , Fabio Dominguez , José Guilherme Milhano

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

A next step in development of the KrkNLO method of including complete NLO QCD corrections to hard processes in a LO parton-shower Monte Carlo (PSMC) is presented. It consists of generalisation of the method, previously used for the…

High Energy Physics - Phenomenology · Physics 2016-12-21 S. Jadach , W. Placzek , S. Sapeta , A. Siodmok , M. Skrzypek

We present a generalization of the $x$-space $\texttt{Candia}$ algorithm to next-to-next-to-next-to-leading order (N$^3$LO) accuracy in Quantum Chromodynamics (QCD) for solving the DGLAP evolution equations for unpolarized parton densities…

High Energy Physics - Phenomenology · Physics 2026-03-24 Casey Hampson , Marco Guzzi

We carry out extensive tests of the next-to-leading logarithmic (NLL) accuracy of the PanScales parton showers, as introduced recently for colour-singlet production in hadron collisions. The tests include comparisons to (semi-)analytic NLL…

High Energy Physics - Phenomenology · Physics 2022-11-23 Melissa van Beekveld , Silvia Ferrario Ravasio , Keith Hamilton , Gavin P. Salam , Alba Soto-Ontoso , Gregory Soyez , Rob Verheyen

The energy dependence for the singlet sector of Parton Distributions Functions (PDFs) is described by an entangled pair of ordinary linear differential equations. Although there are no exact analytic solutions, it is possible to provide…

High Energy Physics - Phenomenology · Physics 2024-02-28 Andrea Simonelli

In this paper, we discuss the algorithms used in the LO evolution program for nondiagonal parton distributions in the DGLAP region and discuss the stability of the code. Furthermore, we demonstrate that we can reproduce the case of the LO…

High Energy Physics - Phenomenology · Physics 2007-05-23 Andreas Freund , Vadim Guzey

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 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