English
Related papers

Related papers: Confronting lattice parton distributions with glob…

200 papers

We present a first determination of the nuclear parton distribution functions (nPDF) based on the NNPDF methodology: nNNPDF1.0. This analysis is based on neutral-current deep-inelastic structure function data and is performed up to NNLO in…

High Energy Physics - Phenomenology · Physics 2019-07-23 Rabah Abdul Khalek , Jacob J. Ethier , Juan Rojo

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

Calculation of moments of generalized parton distributions in lattice QCD requires more powerful techniques than those previously used to calculate moments of structure functions. Hence, we present a novel approach that exploits the full…

High Energy Physics - Lattice · Physics 2009-09-29 Philipp Hagler , John Negele , Dru Renner , Wolfram Schroers , Thomas Lippert , Klaus Schilling

Lattice quantum chromodynamics (QCD) calculations share a defining challenge by requiring a small finite range of spatial separation $z$ between quark/gluon bilinears for controllable power corrections in the perturbative QCD factorization,…

PDFs can be studied directly using lattice QCD by evaluating matrix elements of non-local operators. A number of groups are pursuing numerical calculations and investigating possible systematic uncertainties. One systematic that has…

High Energy Physics - Lattice · Physics 2018-11-08 Raúl A. Briceño , Juan V. Guerrero , Maxwell T. Hansen , Christopher J. Monahan

In global QCD fits of parton distribution functions (PDFs), a large part of the estimated uncertainty on the PDFs originates from the choices of parametric functional forms and fitting methodology. We argue that these types of uncertainties…

High Energy Physics - Phenomenology · Physics 2023-02-21 Aurore Courtoy , Joey Huston , Pavel Nadolsky , Keping Xie , Mengshi Yan , C. -P. Yuan

A new and simple statistical approach is performed to calculate the parton distribution functions (PDFs) of the nucleon in terms of light-front kinematic variables. We do not put in any extra arbitrary parameter or corrected term by hand,…

High Energy Physics - Phenomenology · Physics 2009-03-12 Yunhua Zhang , Lijing Shao , Bo-Qiang Ma

The formulas directly connecting parton distribution functions (PDFs) at the leading (LO) and the next to leading (NLO) QCD orders are applied to both unpolarized and polarized valence PDFs and produce improved LO results on these…

High Energy Physics - Phenomenology · Physics 2014-03-11 O. Yu. Shevchenko , R. R. Akhunzyanov

Global QCD analyses of nuclear parton distribution functions (nPDFs) have traditionally relied on the Hessian method for uncertainty estimation. However, the inherent Gaussian approximation and reliance on local curvature often prove…

High Energy Physics - Phenomenology · Physics 2026-03-16 N. Derakhshanian , P. Risse , T. Jezo , M. Klasen , K. Kovarik , A. Kusina

Parton distribution functions (PDFs) with QED corrections extracted from the QED$\otimes$QCD DGLAP evolution equations in the framework of "valon" model. Our results for the PDFs with QED corrections in this phenomenological model are in…

High Energy Physics - Phenomenology · Physics 2017-10-25 Marzieh Mottaghizadeh , Fatemeh Taghavi Shahri , Parvin Eslami

A study is presented of the impact of simulated inclusive Electron Ion Collider Deep Inelastic Scattering data on the determination of the proton and nuclear parton distribution functions (PDFs) at next-to-next-to-leading and…

High Energy Physics - Phenomenology · Physics 2024-03-18 Néstor Armesto , Thomas Cridge , Francesco Giuli , Lucian Harland-Lang , Paul Newman , Barak Schmookler , Robert Thorne , Katarzyna Wichmann

We present a new global QCD analysis of nuclear parton distribution functions. In addition to the most commonly analyzed data sets for deep inelastic scattering of charged leptons off nuclei and Drell Yan di-lepton production, we include…

High Energy Physics - Phenomenology · Physics 2012-04-18 Daniel de Florian , Rodolfo Sassot , Marco Stratmann , Pia Zurita

The question how the spin of the nucleon is distributed among its quark and gluon constituents is still a subject of intense investigations. Lattice QCD has progressed to provide information about spin fractions and orbital angular momentum…

High Energy Physics - Phenomenology · Physics 2012-08-15 M. Altenbuchinger , Ph. Hägler , W. Weise , E. M. Henley

We report recent studies of the Asymmetry Analysis Collaboration (AAC) on polarized parton distribution functions (PDFs). Using the data on the spin symmetry A_1 in deep inelastic lepton scattering, we investigate optimum polarized PDFs.…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Hirai , S. Kumano , N. Saito

We present the first determination of parton distributions of the nucleon at NLO and NNLO based on a global data set which includes LHC data: NNPDF2.3. Our data set includes, besides the deep inelastic, Drell-Yan, gauge boson production and…

We present a comprehensive study of the lowest moments of nucleon generalized parton distributions in N_f=2+1 lattice QCD using domain wall valence quarks and improved staggered sea quarks. Our investigation includes helicity dependent and…

Parton distribution functions (PDFs) describe universal properties of bound states and allow us to calculate scattering amplitudes in processes with large momentum transfer. Calculating PDFs involves the evaluation of matrix elements with a…

High Energy Physics - Lattice · Physics 2025-02-10 Mari Carmen Bañuls , Krzysztof Cichy , C. -J. David Lin , Manuel Schneider

We present the software framework underlying the NNPDF4.0 global determination of parton distribution functions (PDFs). The code is released under an open source licence and is accompanied by extensive documentation and examples. The code…

Global perturbative QCD analyses, based on large data sets from electron-proton and hadron collider experiments, provide tight constraints on the parton distribution function (PDF) in the proton. The extension of these analyses to nuclear…

High Energy Physics - Phenomenology · Physics 2011-07-29 Paloma Quiroga-Arias , Jose Guilherme Milhano , Urs Achim Wiedemann

The recent measurement of the differential $ \gamma+c $-jet cross section, performed at the Tevatron collider in Run II by the D0 collaboration, is studied in a next-to-leading order (NLO) global QCD analysis to assess its impact on the…

High Energy Physics - Phenomenology · Physics 2017-04-05 Alireza Aleedaneshvar , Muhammad Goharipour , Saeedeh Rostami