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Related papers: The PDF4LHC Working Group Interim Recommendations

200 papers

We study several sources of theoretical uncertainty in the determination of parton distributions (PDFs) which may affect current PDF sets used for precision physics at the Large Hadron Collider, and explain discrepancies between them. We…

High Energy Physics - Phenomenology · Physics 2013-05-09 The NNPDF Collaboration , Richard D. Ball , Valerio Bertone , Luigi Del Debbio , Stefano Forte , Alberto Guffanti , Juan Rojo , Maria Ubiali

I present the results from the recent PDF4LHC study, and the resulting new recommendation for combining PDFs sets for LHC calculations. In order to put this into context I summarise continuing updates in PDFs. This includes improvements and…

High Energy Physics - Phenomenology · Physics 2016-05-11 R. S. Thorne

We study uncertainties of the predicted inclusive Higgs production cross section due to the uncertainties of parton distribution functions (PDF). Particular attention is given to bbH Yukawa coupling enhanced production mechanisms in beyond…

High Energy Physics - Phenomenology · Physics 2009-11-11 Alexander Belyaev , Jon Pumplin , Wu-Ki Tung , C. --P. Yuan

We present NNPDF3.0, the first set of parton distribution functions (PDFs) determined with a methodology validated by a closure test. NNPDF3.0 uses a global dataset including HERA-II deep-inelastic inclusive cross-sections, the combined…

We determine the uncertainty on the strong coupling alpha_S due to the experimental errors on the data fitted in global analysis of hard-scattering data, within the standard framework of leading-twist fixed-order collinear factorisation in…

High Energy Physics - Phenomenology · Physics 2009-11-22 A. D. Martin , W. J. Stirling , R. S. Thorne , G. Watt

In this contribution we briefly report on the progress and open problems in parton distribution functions (PDFs), with emphasis on their implications for LHC phenomenology. Then we study the impact of the recent ATLAS and CMS W lepton…

High Energy Physics - Phenomenology · Physics 2022-03-02 Juan Rojo

The full exploitation of the increasingly precise LHC measurements is essential in order to reduce the uncertainty of theoretical predictions at hadron colliders. The NNPDF2.3 fit was the first PDF determination including the effect of the…

High Energy Physics - Phenomenology · Physics 2014-07-14 Maria Ubiali

We present recent results of the NNPDF collaboration on a full DIS analysis of Parton Distribution Functions (PDFs). Our method is based on the idea of combining a Monte Carlo sampling of the probability measure in the space of PDFs with…

High Energy Physics - Phenomenology · Physics 2008-05-21 NNPDF Collaboration , M. Ubiali , R. D. Ball , L. Del Debbio , S. Forte , A. Guffanti , J. I. Latorre , A. Piccione , J. Rojo

Nuclear parton distribution functions (nuclear PDFs), collinearly factorizable in perturbative QCD (pQCD), are currently extracted most reliably from global analyses of experimental data. Recently, the progress in this field has been driven…

High Energy Physics - Phenomenology · Physics 2022-11-17 Petja Paakkinen

We review the next generation global PDF sets: NNPDF3.0, MMHT14 and CT14. We describe the global datasets, particularly the new data from LHC Run 1, recent developments in QCD theory and PDF methodology, improvements in combination and…

High Energy Physics - Phenomenology · Physics 2016-04-20 Richard D. Ball

This report summarizes the latest developments in the CTEQ-TEA global analysis of parton distribution functions (PDFs) in the nucleon. The focus is on recent NNLO fits to high-precision LHC data at 8 and 13 TeV, including Drell-Yan, jet,…

High Energy Physics - Phenomenology · Physics 2024-11-26 A. Ablat , A. Courtoy , S. Dulat , M. Guzzi , T. J. Hobbs , T. -J. Hou , J. Huston , K. Mohan , H. -W. Lin , P. Nadolsky , I. Sitiwaldi , K. Xie , M. Yan , C. -P. Yuan

We present NNPDF4.0MC, a variant of the NNPDF4.0 set of parton distributions (PDFs) at LO, NLO and NNLO, with and without inclusion of the photon PDF, suitable for use with Monte Carlo (MC) event generators, which require PDFs to satisfy…

High Energy Physics - Phenomenology · Physics 2024-08-29 Juan Cruz-Martinez , Stefano Forte , Niccolo Laurenti , Tanjona R. Rabemananjara , Juan Rojo

We present the MCscales approach for incorporating scale uncertainties in parton distribution functions (PDFs). The new methodology builds on the Monte Carlo sampling for propagating experimental uncertainties into the PDF space that…

High Energy Physics - Phenomenology · Physics 2023-03-27 Zahari Kassabov , Maria Ubiali , Cameron Voisey

We summarise recent developments in the path towards the "MMHT19" parton distribution functions. We concentrate on the extraction of the strange quark upon the improvement of theoretical calculations for NNLO charged current cross sections;…

High Energy Physics - Phenomenology · Physics 2019-07-19 R. S. Thorne , S. Bailey , T. Cridge , L. A. Harland-Lang , A. D. Martin , R. Nathvani

The parton distribution functions (PDFs) which characterize the structure of the proton are currently one of the dominant sources of uncertainty in the predictions for most processes measured at the Large Hadron Collider (LHC). Here we…

We have presented the results of our next-to-next-to-leading order (NNLO) QCD analysis of nuclear parton distribution functions (nuclear PDFs) [Phys. Rev. D 93 (2016) 014026, arXiv:1601.00939 [hep-ph]] using all available neutral current…

High Energy Physics - Phenomenology · Physics 2020-12-17 S. Atashbar Tehrani

We review the current status of spin-averaged and spin-dependent parton distribution functions (PDFs) of the nucleon. After presenting the formalism used to fit PDFs in modern global data analyses, we discuss constraints placed on the PDFs…

High Energy Physics - Phenomenology · Physics 2015-06-16 P. Jimenez-Delgado , W. Melnitchouk , J. F. Owens

We examine the dependence of parton distribution functions (PDFs) on the value of the QCD coupling strength $\alpha_{s}(M_{Z})$. We explain a simple method that is rigorously valid in the quadratic approximation normally applied in PDF…

High Energy Physics - Phenomenology · Physics 2014-11-20 Hung-Liang Lai , Joey Huston , Zhao Li , Pavel Nadolsky , Jon Pumplin , Daniel Stump , C. -P. Yuan

We present updated predictions for the cross-sections for pair production of squarks and gluinos at the LHC Run II. First of all, we update the calculations based on NLO+NLL partonic cross-sections by using the NNPDF3.0NLO global analysis.…

High Energy Physics - Phenomenology · Physics 2016-03-23 Wim Beenakker , Christoph Borschensky , Michael Krämer , Anna Kulesza , Eric Laenen , Simone Marzani , Juan Rojo

We compare predictions for high energy neutrino and anti-neutrino deep inelastic scattering cross-sections within the conventional DGLAP formalism of next-to-leading order QCD, using the latest parton distribution functions such as CT10,…

High Energy Physics - Phenomenology · Physics 2015-05-30 Amanda Cooper-Sarkar , Philipp Mertsch , Subir Sarkar