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Related papers: Parton Distributions for LO Calculations

200 papers

Collider data can play an important role in determining the parton distribution functions of the nucleon. I present a formalism which makes it possible to use next-to-leading order calculations in such a determination, while minimizing the…

High Energy Physics - Phenomenology · Physics 2009-10-30 David A. Kosower

Parton distributions of pseudoscalar pi,K and eta mesons obtained within the NJL model using the Pauli-Villars regularization method are analyzed in terms of LO and NLO evolution, and the valence sea quark and gluon parton distributions for…

High Energy Physics - Phenomenology · Physics 2014-11-17 R. M. Davidson , E. Ruiz Arriola

Generalized parton distributions provide a unified parameterization of hadron structure and allow one to combine information from many different observables. Lattice QCD calculations already provide important input to determine these…

High Energy Physics - Phenomenology · Physics 2010-04-05 M. Diehl , A. Manashov , A. Schafer

A few changes to the routines that calculate CTEQ parton distribution functions allow modern compilers to optimize the evaluations, while having no quantitative effect on the results. Overall computation time is reduced by a factor of 4-5…

High Energy Physics - Phenomenology · Physics 2009-11-10 Zack Sullivan

The choice of a factorization scheme suitable for Monte Carlo simulations of NLO initial state parton showers is discussed in this contribution.

High Energy Physics - Phenomenology · Physics 2008-11-13 Karel Kolar

In this talk an introduction to generalized parton distributions is given. Recent developments are shortly reviewed, including non-perturbative calculations, phenomenological aspects and evaluation of higher order perturbative and power…

High Energy Physics - Phenomenology · Physics 2015-06-25 D. Müller

We give a prescription for attaching parton showers to next-to-leading order (NLO) partonic jet cross sections in electron-positron annihilation. Our method effectively extends to NLO the scheme of Catani, Krauss, Kuhn, and Webber for…

High Energy Physics - Phenomenology · Physics 2007-05-23 Zoltan Nagy , Davison E. Soper

I present a brief summary of the most important updates in the MRST determinations of the NLO and NNLO parton distributions. I concentrate on uncertainties due to input assumptions and possible theoretical corrections, particularly isospin…

High Energy Physics - Phenomenology · Physics 2007-05-23 R. S. Thorne , A. D. Martin , R. G. Roberts , W. J. Stirling

The determination of parton distribution functions in the nucleon and nuclei is important for obtaining precise hadron-reaction cross sections, from which any new exotic signature could be found. We show that a future neutrino factory could…

High Energy Physics - Phenomenology · Physics 2009-11-07 S. Kumano

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 merging of matrix elements and parton showers is an established calculational tool for the description of multi-jet final states at hadron colliders. These methods have recently been promoted to next-to-leading order accuracy in the…

High Energy Physics - Phenomenology · Physics 2013-11-15 Marek Schonherr , Stefan Hoeche , Frank Krauss , Frank Siegert

We present a method to combine next-to-leading order (NLO) matrix elements in QCD with leading logarithmic parton showers by applying a suitably modified version of the phase-space-slicing method. The method consists of subsuming the NLO…

High Energy Physics - Phenomenology · Physics 2009-10-31 B. Pötter

Precision computation of hadronic physics with lattice QCD is becoming feasible. The last decade has seen percent-level calculations of many simple properties of mesons, and the last few years have seen calculations of baryon masses,…

High Energy Physics - Lattice · Physics 2012-07-12 Dru B. Renner

We present a new analysis of parton distributions of the proton. This incorporates a wide range of new data, an improved treatment of heavy flavours and a re-examination of prompt photon production. The new set (MRST) shows systematic…

High Energy Physics - Phenomenology · Physics 2007-05-23 R. G Roberts

We present the first NNPDF full set of Parton Distribution Functions from a comprehensive DIS analysis. This approach, combining a Monte Carlo sampling of the probability measure in the space of PDFs with the use of neural networks as…

High Energy Physics - Phenomenology · Physics 2009-11-13 Maria Ubiali

I review recent progress in the determination of the parton structure of the nucleon, in particular from deep-inelastic structure functions. I explain how the needs of current and future precision phenomenology, specifically at the LHC,…

High Energy Physics - Phenomenology · Physics 2015-06-25 Stefano Forte

We report the polarized parton distributions proposed by the Asymmetry Analysis Collaboration (AAC). Using parametrized distributions at Q^2=1 GeV^2 and measured A_1 data, we determine optimum polarized distributions in the leading order…

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

We propose an extension of matrix element plus parton shower merging at tree level to preserve inclusive cross sections obtained from the merged and showered sample. Implementing this constraint generates approximate next-to-leading order…

High Energy Physics - Phenomenology · Physics 2015-06-12 Simon Platzer

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

In recent years, there has been a breakthrough in lattice calculations of $x$-dependent partonic distributions. This encompasses also distributions describing the 3D structure of the nucleon, such as generalized parton distributions (GPDs).…