English
Related papers

Related papers: Implementing NLO DGLAP evolution in Parton Showers

200 papers

We apply the MC@NLO approach to the process of heavy flavour hadroproduction. MC@NLO is a method for matching next-to-leading order (NLO) QCD calculations and parton shower Monte Carlo (MC) simulations, with the following features: fully…

High Energy Physics - Phenomenology · Physics 2009-11-10 S. Frixione , P. Nason , B. R. Webber

We discuss extensions the CKKW-L and UMEPS tree-level matrix element and parton shower merging approaches to next-to-leading order accuracy. The generalisation of CKKW-L is based on the NL3 scheme previously developed for e+e-…

High Energy Physics - Phenomenology · Physics 2015-06-12 Leif Lonnblad , Stefan Prestel

We formulate PanScales parton showers for hadron collisions so as to achieve next-to-leading logarithmic (NLL) accuracy across a broad set of observables. We do so specifically for colour singlet production. Relative to the existing…

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

We present Monte Carlo data showing the comparison between the parton shower generated by the standard DGLAP-CS kernels and that generated with the new IR-improved DGLAP-CS kernels recently developed by one of us(BFLW). We do this in the…

High Energy Physics - Phenomenology · Physics 2010-03-02 S. Joseph , S. Majhi , B. F. L. Ward , S. A. Yost

We present the interplay between the new IR-improved DGLAP-CS theory and the precision of NLO parton shower/ME matched MC`s as it is realized by the new MC Herwiri1.031 in interface to MC@NLO. We discuss phenomenological implications using…

High Energy Physics - Phenomenology · Physics 2013-02-05 B. F. L. Ward , S. K. Majhi , A. Mukhopadhyay , S. A. Yost

The interpretation of experimental measurements at the LHC requires accurate theoretical predictions for exclusive observables, and in particular the summation of soft and collinear radiation to all orders in perturbation theory. We report…

High Energy Physics - Phenomenology · Physics 2015-02-13 Michael Czakon , Michael Krämer , Malgorzata Worek

The next-to-leading order (NLO) corrections to Drell-Yan slepton pair production are merged with parton shower evolution via the POWHEG method in Herwig++. The NLO corrections at the level of event generation alter the shape of observables…

High Energy Physics - Phenomenology · Physics 2012-08-02 Ilan Fridman-Rojas , Peter Richardson

This document describes a Fortran 95 package for carrying out DGLAP evolution and other common manipulations of parton distribution functions (PDFs). The PDFs are represented on a grid in x-space so as to avoid limitations on the functional…

High Energy Physics - Phenomenology · Physics 2010-03-25 Gavin P. Salam , Juan Rojo

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

This lecture discusses the physics implemented by Monte Carlo event generators for hadron colliders. It details the construction of parton showers and the matching of parton showers to fixed-order calculations at higher orders in…

High Energy Physics - Phenomenology · Physics 2015-06-19 Stefan Höche

A NNLO analysis of certain logarithmic expansions, developed for precision studies of the evolution of the QCD parton distributions (pdf) at the Large Hadron Collider, is presented. We elaborate on their relations to all the solutions of…

High Energy Physics - Phenomenology · Physics 2010-03-25 Alessandro Cafarella , Claudio Coriano' , Marco Guzzi

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

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

I give an overview of the recent progress on the matching of fixed-order calculations and parton showers. The focus is on the matching with NNLO QCD corrections as well as with NLO EW ones.

High Energy Physics - Phenomenology · Physics 2021-10-06 Emanuele Re

It is anticipated that hard double parton scatterings will occur frequently in the collisions of the LHC, producing interesting signals and significant backgrounds to certain single scattering processes. For double scattering processes in…

High Energy Physics - Phenomenology · Physics 2015-03-13 Jonathan R. Gaunt , W. James Stirling

We present recent progress towards a global determination of parton distribution functions (PDFs) at approximate N$^3$LO (aN$^3$LO) accuracy within the NNPDF framework. We construct a parametrisation of the $\mathcal{O}(\alpha_s^4)$ QCD…

High Energy Physics - Phenomenology · Physics 2023-06-28 Felix Hekhorn , Giacomo Magni

Parton shower event generators typically approximate evolution of QCD color so that only contributions that are leading in the limit of an infinite number of colors are retained. Our parton shower generator, Deductor, has used an "LC+"…

High Energy Physics - Phenomenology · Physics 2019-03-27 Zoltan Nagy , Davison E. Soper

In this note we outline the Monte Carlo project {\tt KrkMC}. The goal of this project is to construct a QCD Parton Shower accurate to NLO level in both coefficient function and splitting function (shower) parts. We discuss in detail one of…

High Energy Physics - Phenomenology · Physics 2014-07-24 M. Skrzypek , O. Gituliar , S. Jadach , A. Kusina

We show how a careful analysis of the behaviour of a parton shower Monte Carlo in the vicinity of the soft and collinear regions allows one to formulate a modified MC@NLO-matching prescription that reduces the number of negative-weight…

High Energy Physics - Phenomenology · Physics 2020-08-26 R. Frederix , S. Frixione , S. Prestel , P. Torrielli

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