English
Related papers

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

200 papers

The precise knowledge of parton distribution functions (PDFs) is indispensable to the accurate calculation of hadron-initiated QCD hard scattering observables. Much of our information on PDFs is extracted by comparing deep inelastic…

High Energy Physics - Phenomenology · Physics 2013-10-03 David Westmark

We study the sources of systematic errors in the measurement of the W to lepton and neutrino cross-sections at the LHC. We consider the systematic errors in both the total cross-section and acceptance for anticipated experimental cuts. We…

High Energy Physics - Phenomenology · Physics 2009-02-18 Nadia E. Adam , Valerie Halyo , Scott A. Yost , Wenhan Zhu

We present an updated determination of nuclear parton distributions (nPDFs) from a global NLO QCD analysis of hard processes in fixed-target lepton-nucleus and proton-nucleus together with collider proton-nucleus experiments. In addition to…

High Energy Physics - Phenomenology · Physics 2022-05-27 Rabah Abdul Khalek , Rhorry Gauld , Tommaso Giani , Emanuele R. Nocera , Tanjona R. Rabemananjara , Juan Rojo

Precision predictions for phenomenologically interesting observables such as the t-tbar invariant mass distribution and forward-backward asymmetry in top-quark pair production at hadron colliders require control over the differential cross…

High Energy Physics - Phenomenology · Physics 2015-03-13 Valentin Ahrens , Andrea Ferroglia , Matthias Neubert , Ben D. Pecjak , Li Lin Yang

We study the sources of systematic errors in the measurement of the Z to ll cross-sections at the LHC. We consider the systematic errors in both the total cross-section and acceptance for anticipated experimental cuts. We include the best…

High Energy Physics - Phenomenology · Physics 2011-03-23 Nadia E. Adam , Valerie Halyo , Scott A. Yost

We study the QCD sources of systematic uncertainties in the experimental extraction of the W cross section at hadron colliders. The uncertainties appear in the evaluation of the detector acceptances used to convert the number of observed…

High Energy Physics - Phenomenology · Physics 2011-03-23 S. Frixione , M. L. Mangano

We compare double-differential normalized production cross sections for top-antitop $+ X$ hadroproduction at NNLO QCD accuracy, as obtained through a customized version of the MATRIX framework interfaced to PineAPPL, with recent data by the…

High Energy Physics - Phenomenology · Physics 2023-12-07 Maria Vittoria Garzelli , Javier Mazzitelli , Sven-Olaf Moch , Oleksandr Zenaiev

We report the parton distribution functions (PDFs) determined from the NNLO QCD analysis of the world inclusive DIS data with account of the precise NNLO QCD corrections to the evolution equations kernel. The value of strong coupling…

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

In this talk we present a determination of the strong coupling constant $\alpha_\text{s}$ and its energy-scale dependence based on a next-to-next-to-leading order (NNLO) QCD analysis of dijet production. Using the invariant mass of the…

High Energy Physics - Phenomenology · Physics 2025-07-03 João Pires

We present LO, NLO and NNLO sets of parton distribution functions (PDFs) of the proton determined from global analyses of the available hard scattering data. These MMHT2014 PDFs supersede the `MSTW2008' parton sets, but are obtained within…

High Energy Physics - Phenomenology · Physics 2015-06-11 L. A. Harland-Lang , A. D. Martin , P. Motylinski , R. S. Thorne

Global analyses of Parton Distribution Functions (PDFs) have provided incisive constraints on the up and down quark components of the proton, but constraining the other flavor degrees of freedom is more challenging. Higher-order theory…

High Energy Physics - Phenomenology · Physics 2012-05-29 A. Kusina , T. Stavreva , S. Berge , F. I. Olness , I. Schienbein , K. Kovarik , T. Jezo , J. Y. Yu , K. Park

The `XIIIth Quark Confinement and the Hadron Spectrum' conference (Confinement 2018) contained a `Round Table Discussion' on the status of the determinations of the strong coupling $\alpha_s(m_Z)$ as well as prospects for future…

High Energy Physics - Phenomenology · Physics 2018-12-17 Antonio Pich , Juan Rojo , Rainer Sommer , Antonio Vairo

We extract the ratio of the down (d) and up (u) parton distribution functions (PDF's) from the ratio of deuteron and proton structure function F_2(d)/F_2(p) measured by NMC. We use corrections for nuclear binding effects in the deuteron,…

High Energy Physics - Phenomenology · Physics 2007-05-23 U. K. Yang , A. Bodek

We present an updated global analysis of collinearly factorized nuclear parton distribution functions (PDFs) at next-to-leading order in perturbative QCD. In comparison to our previous fit, EPPS16, the present analysis includes more data…

High Energy Physics - Phenomenology · Physics 2022-05-25 Kari J. Eskola , Petja Paakkinen , Hannu Paukkunen , Carlos A. Salgado

We present a determination of a set of polarized parton distributions (PDFs) of the nucleon, at next-to-leading order, from a global set of longitudinally polarized deep-inelastic scattering data: NNPDFpol1.0. The determination is based on…

High Energy Physics - Phenomenology · Physics 2013-04-01 The NNPDF Collaboration , Richard D. Ball , Stefano Forte , Alberto Guffanti , Emanuele R. Nocera , Giovanni Ridolfi , Juan Rojo

A survey is given on the present status of the nucleon parton distributions and related precision calculations and precision measurements of the strong coupling constant $\alpha_s(M_Z^2)$. We also discuss the impact of these quantities on…

High Energy Physics - Phenomenology · Physics 2014-11-21 Johannes Blümlein

We present predictions for relevant LHC observables obtained with the NNPDF2.0 set. We compute the combined PDFs uncertainties on these observables, and show that combining errors in quadrature yields an excellent approximation to exact…

High Energy Physics - Phenomenology · Physics 2010-05-05 Maria Ubiali , Richard D. Ball , Luigi Del Debbio , Stefano Forte , Alberto Guffanti , José I. Latorre , Juan Rojo

We address the unphysical energy dependence of quarkonium-hadroproduction cross sections at Next-to-Leading Order (NLO) in alpha_S which we attribute to an over-subtraction in the factorisation of the collinear singularities inside the PDFs…

High Energy Physics - Phenomenology · Physics 2021-06-30 Jean-Philippe Lansberg , Melih Arslan Ozcelik

We present state-of-the-art extractions of the strong coupling based on N$^3$LO+NNLL accurate predictions for the two-jet rate in the Durham clustering algorithm at $e^+e^-$ collisions, as well as a simultaneous fit of the two- and…

We extract new parton distribution functions (PDFs) of the proton by global analysis of hard scattering data in the general-mass framework of perturbative quantum chromodynamics. Our analysis includes new theoretical developments together…

High Energy Physics - Phenomenology · Physics 2010-10-27 Hung-Liang Lai , Marco Guzzi , Joey Huston , Zhao Li , Pavel M. Nadolsky , Jon Pumplin , C. -P. Yuan