Progress in the Determination of the Partonic Structure of the Proton

Abstract

We review the current state of the art in the determination of the parton substructure of the nucleon, as expressed in terms of parton distribution functions (PDFs), and probed in high-energy lepton-hadron and hadron-hadron collisions, and we assess their implications for current precision collider phenomenology, in particular at the Large Hadron Collider (LHC). We review the theoretical foundations of PDF determination: the way cross sections are expressed in terms of PDFs using perturbative QCD factorization and evolution, the methodology used to extract PDFs from experimental data, and the way in which different physical processes can be used to constrain different PDFs. We summarize current knowledge of PDFs and the limitations in accuracy currently entailed for the computation of hadron collider processes, in particular at the LHC. We discuss the current main sources of theoretical and phenomenological uncertainties, and the direction of progress towards their reduction in the future.

50 pages, 9 figures. Invited contribution to Annual Review of Nuclear and Particle Science, Volume 63

References in corpus (25)

• Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC
• Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC
• Parton distributions for the LHC
• New parton distributions for collider physics
• Vector boson production at hadron colliders: a fully exclusive QCD calculation at NNLO
• FEWZ 2.0: A code for hadronic Z production at next-to-next-to-leading order
• The PDF4LHC Working Group Interim Recommendations
• Parton Distributions for LO Generators
• Hard Interactions of Quarks and Gluons: a Primer for LHC Physics
• QCDNUM: Fast QCD Evolution and Convolution
• The PDF4LHC Working Group Interim Report
• Dynamical parton distributions of the nucleon and very small-x physics
• Determination of the strange quark density of the proton from ATLAS measurements of the W->l nu and Z->ll cross sections
• The Charm Parton Content of the Nucleon
• Quantitative constraints on the gluon distribution function in the proton from collider isolated-photon data
• Study of Monte Carlo approach to experimental uncertainty propagation with MSTW 2008 PDFs
• Precision determination of electroweak parameters and the strange content of the proton from neutrino deep-inelastic scattering
• Measurement of the electron charge asymmetry in inclusive W production in pp collisions at sqrt(s) = 7 TeV
• Extended Parameterisations for MSTW PDFs and their effect on Lepton Charge Asymmetry from W Decays
• NNLO Benchmarks for Gauge and Higgs Boson Production at TeV Hadron Colliders
• The Quark and Gluon Structure of the Proton
• Sensitivity of the LHC isolated-gamma+jet data to the parton distribution functions of the proton
• Parton Distribution Uncertainties using Smoothness Prior
• Progress in CTEQ-TEA PDF analysis
• A Comparison of new MC-adapted Parton Densities

Cited by in corpus (85)

• Parton distributions for the LHC Run II
• LHAPDF6: parton density access in the LHC precision era
• Parton distributions from high-precision collider data
• PDF4LHC recommendations for LHC Run II
• QCD and strongly coupled gauge theories: challenges and perspectives
• Constraints on large-$x$ parton distributions from new weak boson production and deep-inelastic scattering data
• The ABM parton distributions tuned to LHC data
• Parton distributions and lattice QCD calculations: a community white paper
• The Structure of the Proton in the LHC Precision Era
• 50 Years of Quantum Chromodynamics
• Parton distributions with small-x resummation: evidence for BFKL dynamics in HERA data
• A guide to light-cone PDFs from Lattice QCD: an overview of approaches, techniques and results
• A determination of the fragmentation functions of pions, kaons, and protons with faithful uncertainties
• Delineating parton distributions and the strong coupling
• The PDF4LHC report on PDFs and LHC data: Results from Run I and preparation for Run II
• A meta-analysis of parton distribution functions
• Investigations into the flavor dependence of partonic transverse momentum
• PDF reweighting in the Hessian matrix approach
• An Unbiased Hessian Representation for Monte Carlo PDFs
• Parton Distributions in Nucleons and Nuclei
• Measurement of the differential and double-differential Drell-Yan cross sections in proton-proton collisions at sqrt(s) = 7 TeV
• Further developments of a multi-phase transport model for relativistic nuclear collisions
• Constraints on the gluon PDF from top quark pair production at hadron colliders
• Multiplicity dependence of (multi-)strange hadron production in proton-proton collisions at $\sqrt{s}$ = 13 TeV
• Hadron structure in high-energy collisions
• Strange quark suppression from a simultaneous Monte Carlo analysis of parton distributions and fragmentation functions
• Systematic uncertainties in parton distribution functions from lattice QCD simulations at the physical point
• Measurements of differential and double-differential Drell-Yan cross sections in proton-proton collisions at 8 TeV
• aMCfast: automation of fast NLO computations for PDF fits
• Precision determination of the small-$x$ gluon from charm production at LHCb
• The asymptotic behaviour of parton distributions at small and large $x$
• Pinning down the large-x gluon with NNLO top-quark pair differential distributions
• Confronting current NLO parton fragmentation functions with inclusive charged-particle spectra at hadron colliders
• Towards Ultimate Parton Distributions at the High-Luminosity LHC
• Parton distributions with threshold resummation
• Impact of hadronic and nuclear corrections on global analysis of spin-dependent parton distributions
• Flavor Structure of the Nucleon Sea
• Nuclear Structure Functions at a Future Electron-Ion Collider
• Accessing proton generalized parton distributions and pion distribution amplitudes with the exclusive pion-induced Drell-Yan process at J-PARC
• Pion structure function from leading neutron electroproduction and SU(2) flavor asymmetry
• Do we need N${}^3$LO Parton Distributions?
• Measurement of differential cross sections and $W^{+}/W^{-}$ cross-section ratios for $W$ boson production in association with jets at $\sqrt{s}=8$ TeV with the ATLAS detector
• Probing the small-$x$ nuclear gluon distributions with isolated photons at forward rapidities in p+Pb collisions at the LHC
• Effects of TMD evolution and partonic flavor on $e^{+}{e}^{-}$ annihilation into hadrons
• Direct photon production and PDF fits reloaded
• The effect on PDFs and ${\alpha }_S(M_Z^2)$ due to changes in flavour scheme and higher twist contributions
• Towards parton distribution functions with small-$x$ resummation: HELL 2.0
• Ratios of $W$ and $Z$ cross sections at large boson $p_T$ as a constraint on PDFs and background to new physics
• Nuclear PDFs in the beginning of the LHC era
• Anatomy of the Higgs fits: a first guide to statistical treatments of the theoretical uncertainties
• A perturbative QCD study of dijets in p+Pb collisions at the LHC
• Constraining the SMEFT with Bayesian reweighting
• Hadron mass corrections in semi-inclusive deep-inelastic scattering
• Interplay of Threshold Resummation and Hadron Mass Corrections in Deep Inelastic Processes
• Parton distributions from nonlocal chiral SU(3) effective theory: Flavor asymmetries
• Improved nonsinglet QCD analysis of the fixed-target DIS data
• Bayesian reweighting of nuclear PDFs and constraints from proton-lead collisions at the LHC
• Probing the gluon density of the proton in the exclusive photoproduction of vector mesons at the LHC: A phenomenological analysis
• Impact of JLab data on the determination of GPDs at zero skewness and new insights from transition form factors $N\to \Delta$
• Direct observation of quark-hadron duality in the free neutron F_2 structure function
• Impact of unidentified light charged hadron data on the determination of pion fragmentation functions
• Production of electroweak bosons at hadron colliders: theoretical aspects
• What are the low-$Q$ and large-$x$ boundaries of collinear QCD factorization theorems?
• Analysis of identified particle transverse momentum spectra produced in pp, p--Pb and Pb--Pb collisions at the LHC using Tsallis--Pareto-type function
• Progress in the NNPDF global analysis and the impact of the legacy HERA combination
• Nucleon microscopy in proton-nucleus scattering via analysis of bremsstrahlung emission
• Large-x connections of nuclear and high-energy physics
• Multi-variable integration with a variational quantum circuit
• Probing gluon helicity with heavy flavor at the EIC
• Twist-3 Contributions in Semi-Inclusive DIS in the Target Fragmentation Region
• The impact of the LHCb $B^{\pm }$ production cross-section on parton distribution functions and determining the mass of heavy quarks
• A compression algorithm for the combination of PDF sets
• Nuclear gluons at RHIC in a multi-observable approach
• PDF4LHC recommendations for Run II
• Inclusive gauge boson production in the color dipole formalism
• Proton structure at the LHC
• Can sea quark asymmetry shed light on the orbital angular momentum of the proton?
• Dipole Splitting Algorithm -- A practical algorithm to use the dipole subtraction procedure --
• Parton Distributions in the Higgs Boson Era
• The Standard Model from the LHC to future colliders: a contribution to the Workshop "What Next" of INFN
• Constraining nPDFs with inclusive pions and direct photons at forward rapidities in p+Pb collisions at the LHC
• Comparative insights into gluon and proton structure through parton distribution functions
• Empirical Bayes unfolding of elementary particle spectra at the Large Hadron Collider
• Closure testing NNPDF3.0 with LHC observables
• Parton distributions based on a maximally consistent dataset