English
Related papers

Related papers: HERAFitter, Open Source QCD Fit Project

200 papers

We present new sets of nuclear parton distribution functions (nPDFs) at next-to-leading order (NLO) and next-to-next-to-leading order (NNLO). Our analyses are based on deeply inelastic scattering data with charged-lepton and neutrino beams…

High Energy Physics - Phenomenology · Physics 2019-12-17 Marina Walt , Ilkka Helenius , Werner Vogelsang

A robust uncertainty estimate in global analyses of Parton Distribution Functions (PDFs) is essential at the Large Hadron Collider (LHC), especially in view of the high-precision data anticipated by experimentalists in the High-Luminosity…

High Energy Physics - Phenomenology · Physics 2026-04-14 Mark N. Costantini , Luca Mantani , James M. Moore , Maria Ubiali

The current analysis aims to present the results of a QCD analysis of diffractive parton distribution functions (diffractive PDFs) at next-to-leading order (NLO) accuracy in perturbative QCD. In this new determination of diffractive PDFs,…

High Energy Physics - Phenomenology · Physics 2019-09-20 Atefeh Maktoubian , Hossein Mehraban , Hamzeh Khanpour , Muhammad Goharipour

We present a new global determination of the helicity-dependent parton distribution functions (PDFs) of the proton, based on inclusive deep-inelastic scattering (DIS) and semi-inclusive DIS (SIDIS) data within a consistent next-to-leading…

High Energy Physics - Phenomenology · Physics 2026-02-20 Hamzeh Khanpour , Maryam Soleymaninia , Majid Azizi , Michael Klasen , Hadi Hashamipour , Maral Salajegheh , Ulf-G. Meißner

The high precision and large kinematic coverage of the data from the HERA-I running period (1994-2000) have already allowed precise extractions of proton parton distribution functions (PDFs). The HERA-II running program is now underway and…

High Energy Physics - Experiment · Physics 2007-05-23 C. Gwenlan

Accurate Standard Model predictions of proton-proton collisions are essential for interpreting the current and forthcoming experimental measurements from high-energy colliders. The quest for physics beyond the Standard Model is in fact…

High Energy Physics - Phenomenology · Physics 2025-04-09 Giacomo Magni

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 provide an assessment of the impact of parton distributions on the determination of LHC processes, and of the accuracy with which parton distributions (PDFs) can be extracted from data, in particular from current and forthcoming HERA…

Previously published data on inclusive neutral and charged current e+p and e-p deep inelastic scattering from HERA have been combined. The new, model-independent method of combining the measured cross sections takes full account of…

High Energy Physics - Experiment · Physics 2015-05-13 C. Gwenlan

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

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 discuss strategies for comparisons of nonperturbative QCD predictions for parton distribution functions (PDFs) with high-energy experiments in the region of large partonic momentum fractions $x$. Analytic functional forms for PDFs cannot…

High Energy Physics - Phenomenology · Physics 2021-03-31 A. Courtoy , Pavel M. Nadolsky

A QCD fit analysis to the combined HERA inclusive deep inelastic cross sections measured by the H1 and ZEUS collaborations for $e^\pm p$ scattering to extract HERAPDF sets is presented. The results are used for predictions of $ p\bar{p}$…

High Energy Physics - Experiment · Physics 2019-08-14 V. Radescu

The accurate determination of the Parton Distribution Functions (PDFs) of the proton is an essential ingredient of the Large Hadron Collider (LHC) program. PDF uncertainties impact a wide range of processes, from Higgs boson…

A "meta-analysis" is a method for comparison and combination of nonperturbative parton distribution functions (PDFs) in a nucleon obtained with heterogeneous procedures and assumptions. Each input parton distribution set is converted into a…

High Energy Physics - Phenomenology · Physics 2015-06-18 Jun Gao , Pavel Nadolsky

Parton distribution functions (PDFs) describe the structure of hadrons as composed of quarks and gluons. They are needed to make predictions for short-distance processes in high-energy collisions and are determined by fitting to cross…

High Energy Physics - Phenomenology · Physics 2020-11-11 Karol Kovarik , Pavel M. Nadolsky , Davison E. Soper

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 2014-11-20 Paloma Quiroga-Arias , Jose Guilherme Milhano , Urs Achin Wiedemann

The strong force which binds hadrons is described by the theory of Quantum Chromodynamics (QCD). Determining the character and manifestations of QCD is one of the most important and challenging outstanding issues necessary for a…

We present the new MSHT20 set of parton distribution functions (PDFs) of the proton, determined from global analyses of the available hard scattering data. The PDFs are made available at NNLO, NLO, and LO, and supersede the MMHT14 sets.…

High Energy Physics - Phenomenology · Physics 2022-08-22 S. Bailey , T. Cridge , L. A. Harland-Lang , A. D. Martin , R. S. Thorne

The parton distribution functions (PDFs) of the proton are one of the essential ingredients to describe physics processes at hadron colliders. The Z boson production data at the LHC have a potential to constrain PDFs, especially the gluon…

High Energy Physics - Phenomenology · Physics 2016-08-31 Rajdeep M Chatterjee , Monoranjan Guchait , Ringaile Placakyte