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Related papers: Uncertainties on alpha_S in global PDF analyses an…

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We report the value of $\alpha_{\rm s}$ obtained from QCD analysis of existing data on deep-inelastic scattering of charged leptons off proton and deuterium and estimate its theoretical uncertainties with particular attention paid to impact…

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

We review various methods used to estimate uncertainties in quantum correlation functions, such as parton distribution functions (PDFs). Using a toy model of a PDF, we compare the uncertainty estimates yielded by the traditional Hessian and…

High Energy Physics - Phenomenology · Physics 2022-08-17 N. T. Hunt-Smith , A. Accardi , W. Melnitchouk , N. Sato , A. W. Thomas , M. J. White

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 photon parton distribution function (PDF) of the proton is crucial for precise comparisons of LHC cross sections with theoretical predictions. However, it was previously affected by very large uncertainties of around ${\cal O}(100\%)$…

High Energy Physics - Phenomenology · Physics 2024-08-26 Aneesh Manohar , Paolo Nason , Gavin Salam , Giulia Zanderighi

We discuss the determination of electroweak parameters from hadron collider observables, focusing on the $W$ boson mass measurement. We revise the procedures adopted in the literature to include in the experimental analysis the uncertainty…

High Energy Physics - Phenomenology · Physics 2021-02-08 E. Bagnaschi , A. Vicini

In the extra dimension models of ADD and RS we study the dependence of the various parton distribution functions on observable of Drell-Yan process to NLO in QCD at LHC and Tevatron energies. Uncertainties at LHC due to factorisation scales…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. C. Kumar , Prakash Mathews , V. Ravindran

The goal of this study is to find a prescription for defining parton distributions (PDFs) which are most appropriate for use in those codes where only LO matrix elements (MEs) are used, as in many Monte Carlo generators. We describe a…

High Energy Physics - Phenomenology · Physics 2008-07-15 A. Sherstnev , R. S. Thorne

We consider some trends, achievements and a series of remaining problems in the precision determination of parton distribution functions. For the description of the scaling violations of the deep-inelastic scattering data, forming the key…

High Energy Physics - Phenomenology · Physics 2018-09-05 S. Alekhin , J. Bluemlein , S. -O. Moch

The determination of the $W$-boson mass through an analysis of the decay charged-lepton transverse momentum distribution has a sizable uncertainty due to the imperfect knowledge of the relevant parton distribution functions (PDFs). In this…

High Energy Physics - Phenomenology · Physics 2019-09-04 Moh'd Hussein , Joshua Isaacson , Joey Huston

In the context of a recent CTEQ6.6 global analysis, we review a new technique for studying correlated theoretical uncertainties in hadronic observables associated with imperfect knowledge of parton distribution functions (PDFs). The…

High Energy Physics - Phenomenology · Physics 2008-09-08 Pavel M. Nadolsky

We present updated leading-order, next-to-leading order and next-to-next-to-leading order parton distribution functions ("MSTW 2008") determined from global analysis of hard-scattering data within the standard framework of leading-twist…

High Energy Physics - Phenomenology · Physics 2009-09-30 A. D. Martin , W. J. Stirling , R. S. Thorne , G. Watt

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…

In this talk, we introduce our recently completed next-to-leading order (NLO) global analysis of the nuclear parton distribution functions (nPDFs) called EPS09 - a higher order successor to the well-known leading-order (LO) analysis EKS98…

High Energy Physics - Phenomenology · Physics 2014-11-18 H. Paukkunen , K. J. Eskola , C. A. Salgado

The potential of the LHeC, a future electron-proton collider, for precision Deep Inelastic Scattering measurements is reviewed with particular emphasis on the reduction of uncertainties on the parton distribution functions (PDFs) of the…

High Energy Physics - Phenomenology · Physics 2019-08-14 A. M. Cooper-Sarkar

Uncertainties on parton distribution functions (PDFs) compromise discovery at the LHC for any new physics which can be described as a contact-interaction. PDF uncertainties also limit our ability to use W and Z cross-sections as an accurate…

High Energy Physics - Phenomenology · Physics 2007-07-12 A M Cooper-Sarkar

In this talk, we present our recent next-to-leading order (NLO) nuclear parton distribution functions (nPDFs), which we call EPS09. As an extension to earlier NLO analyses, we supplement the deep inelastic scattering and Drell-Yan dilepton…

High Energy Physics - Phenomenology · Physics 2009-11-18 Kari J. Eskola , Hannu Paukkunen , Carlos A. Salgado

We present MAPPDFpol1.0, a new determination of the helicity-dependent parton distribution functions (PDFs) of the proton from a set of longitudinally polarised inclusive and semi-inclusive deep-inelastic scattering data. The determination…

High Energy Physics - Phenomenology · Physics 2025-04-23 MAP , Collaboration , : , Valerio Bertone , Amedeo Chiefa , Emanuele R. Nocera

The LHC has recently released precise measurements of the transverse momentum distribution of the Z-boson that provide a unique constraint on the structure of the proton. Theoretical developments now allow the prediction of these…

High Energy Physics - Phenomenology · Physics 2017-09-13 Radja Boughezal , Alberto Guffanti , Frank Petriello , Maria Ubiali

We perform a global QCD analysis of unpolarized parton distribution functions (PDFs) in the proton, including new $W +$\,charm production data from $pp$ collisions at the LHC and semi-inclusive pion and kaon production data in…

High Energy Physics - Phenomenology · Physics 2025-10-17 Trey Anderson , W. Melnitchouk , N. Sato

We use all the available new precise data for deep inelastic and related hard scattering processes to perform NLO global parton analyses. These new data allow an improved determination of partons and, in particular, the inclusion of the…

High Energy Physics - Phenomenology · Physics 2011-03-23 A. D. Martin , R. G. Roberts , W. J. Stirling , R. S. Thorne