English
Related papers

Related papers: Matrix Element Method at NLO for (anti-)$\mathbf{k…

200 papers

An improved analysis method to extract quark helicity distributions in leading order (LO) QCD from semi-inclusive double spin asymmetries in deep inelastic scattering is presented. The method relies on the fact that fragmentation functions,…

Data Analysis, Statistics and Probability · Physics 2017-03-28 Jörg Pretz

We present a new QCD event generator for hadron collider which can calculate one-, two- and three-jet cross sections at next-to-leading order accuracy. In this letter we study the transverse energy spectrum of three-jet hadronic events…

High Energy Physics - Phenomenology · Physics 2011-05-05 Zoltan Nagy

We report on the next-to-leading order QCD calculation for e+ e- --> 4 jets. We explain some modern techniques which have been used to calculate the one-loop amplitudes efficiently. We further report on the general purpose numerical program…

High Energy Physics - Phenomenology · Physics 2008-11-26 Stefan Weinzierl

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 present an implementation of the calculation of the production of W^+W^+ plus two jets at hadron colliders, at next-to-leading order (NLO) in QCD, in the POWHEG framework, which is a method that allows the interfacing of NLO calculations…

High Energy Physics - Phenomenology · Physics 2015-05-27 Tom Melia , Paolo Nason , Raoul Rontsch , Giulia Zanderighi

We present a study of higher order QCD corrections beyond NLO to processes with an electroweak vector boson, W or Z, in association with jets. We focus on the regions of high transverse momenta of commonly used differential distributions.…

High Energy Physics - Phenomenology · Physics 2015-06-16 Daniel Maître , Sebastian Sapeta

In collider physics, jet algorithms are a ubiquitous tool for clustering particles into discrete jet objects. Event shapes offer an alternative way to characterize jets, and one can define a jet multiplicity event shape, which can take on…

High Energy Physics - Phenomenology · Physics 2015-05-18 Daniele Bertolini , Jesse Thaler , Jonathan R. Walsh

A general method for calculating \NLO cross sections in perturbative QCD is presented. The algorithm is worked out for calculating $N$-jet cross sections in hadron-hadron collisions. The generalization of the scheme to performing…

High Energy Physics - Phenomenology · Physics 2009-10-30 Zoltán Nagy , Zoltán Trócsányi

We compute the next-to-next-to-leading order (NNLO) QCD corrections to the first five moments of six event shape variables related to three-particle final states in electron-positron annihilation; the thrust, the heavy jet mass, the…

High Energy Physics - Phenomenology · Physics 2009-06-11 A. Gehrmann-De Ridder , T. Gehrmann , E. W. N. Glover , G. Heinrich

We discuss the GENEVA Monte Carlo framework, which combines higher-order resummation (NNLL) of large Sudakov logarithms with multiple next-to-leading-order (NLO) matrix-element corrections and parton showering (using PYTHIA8) to give a…

The matrix element method utilizes ab initio calculations of probability densities as powerful discriminants for processes of interest in experimental particle physics. The method has already been used successfully at previous and current…

Computational Physics · Physics 2015-05-20 Doug Schouten , Adam DeAbreu , Bernd Stelzer

In this proceedings we compare phenomenological predictions for differential distributions in top-quark pair production at the LHC. In particular we consider NNLO QCD fixed-order predictions and parton-level predictions based on NLO QCD…

The ALPHA algorithm to evaluate the exact, tree-level matrix elements is reviewed in the context of multi-parton processes in QCD. The algorithm is suited for the authomatic calculation of tree-level scattering amplitudes and allows for…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Moretti

The most precise top quark mass measurements use kinematic reconstruction methods, determining the top mass parameter of a Monte Carlo event generator, $m_t^{\rm MC}$. Due to the complicated interplay of hadronization and parton shower…

High Energy Physics - Phenomenology · Physics 2018-03-07 Bahman Dehnadi , André H. Hoang , Vicent Mateu , Moritz Preisser , Iain W. Stewart

The matrix element method is the LHC inference method of choice for limited statistics. We present a dedicated machine learning framework, based on efficient phase-space integration, a learned acceptance and transfer function. It is based…

High Energy Physics - Phenomenology · Physics 2024-11-13 Theo Heimel , Nathan Huetsch , Ramon Winterhalder , Tilman Plehn , Anja Butter

In this work, two different methods for extracting the mass of a new quark from the (pseudo) data are compared: the classical cut-based method and the matrix element method. As a concrete example a fourth family up type quark is searched in…

High Energy Physics - Phenomenology · Physics 2015-06-05 Erdogan Akyazi , Gokhan Unel , Metin Yilmaz

We address the issues of clustering and non-global logarithms for jet shapes in the process of production of a Higgs/vector boson associated with a single hard jet at hadron colliders. We perform an analytical fixed-order calculation up to…

High Energy Physics - Phenomenology · Physics 2021-07-05 Naima Ziani , Kamel Khelifa-Kerfa , Yazid Delenda

We calculate in the next-to-leading order the impact factor (vertex) for the production of a forward high-$p_T$ jet, in the approximation of small aperture of the jet cone in the pseudorapidity-azimuthal angle plane. The final expression…

High Energy Physics - Phenomenology · Physics 2012-08-17 Dmitry Yu. Ivanov , Alessandro Papa

To explore the interplay of NLO matching and next-to-leading logarithmic (NLL) parton showers, we consider the simplest case of $\gamma^*$ and Higgs-boson decays to $q\bar q$ and $gg$ respectively. Not only should shower NLL accuracy be…

High Energy Physics - Phenomenology · Physics 2023-10-25 Keith Hamilton , Alexander Karlberg , Gavin P. Salam , Ludovic Scyboz , Rob Verheyen

We present a method, based on the positive weight next-to-leading-order matching formalism (POWHEG), to simulate photon production processes at next-to-leading-order (NLO). This technique is applied to the simulation of diphoton production…

High Energy Physics - Phenomenology · Physics 2015-05-28 Luca D'Errico , Peter Richardson