Flavor non-singlet parton distribution functions from lattice QCD at physical quark masses via the pseudo-distribution approach

Abstract

One of the great challenges of QCD is to determine the partonic structure of the nucleon from first principles. In this work, we provide such a determination of the flavor non-singlet ($u-d$) unpolarized parton distribution function (PDF), utilizing the non-perturbative formulation of QCD on the lattice. We apply Radyushkin's pseudo-distribution approach to lattice results obtained using simulations with the light quark mass fixed to its physical value; this is the first ever attempt for this approach directly at the physical point. The extracted coordinate-space matrix elements are used to find the relevant physical Ioffe time distributions from a matching procedure. The full Bjorken-$x$ dependence of PDFs is resolved using several reconstruction methods to tackle the ill-conditioned inverse problem encountered when using discrete lattice data. We consider both the valence distribution $q_v$ and the combination with antiquarks $q_v+2\bar{q}$, related to, respectively, the real and imaginary part of extracted matrix elements. Good agreement is found with PDFs from global fits already within statistical uncertainties and it is further improved by quantifying several systematic effects. The results presented here are the first ever \emph{ab initio} determinations of PDFs fully consistent with global fits in the whole $x$-range. Thus, they pave the way to investigating a wider class of partonic distributions, such as e.g.\ singlet PDFs and generalized parton distributions. Therefore, essential and yet missing first-principle insights can be achieved, complementing the rich experimental programs dedicated to the structure of the nucleon.

arXiv commentMatches journal version. Added an alternative interpolation procedure + analysis of PDF moments + comparison with NNPDF ITDs. Main results and conclusions unchanged. 24 pages, 17 figures

References in corpus (96)

• Parton distributions from high-precision collider data
• Parton Physics on Euclidean Lattice
• Chirally improving Wilson fermions - I. O(a) improvement
• Quasi-PDFs, momentum distributions and pseudo-PDFs
• Large-Momentum Effective Theory
• Exploring hadrons' partonic structure using ab initio lattice QCD calculations
• Nucleon Helicity and Transversity Parton Distributions from Lattice QCD
• Flavor Structure of the Nucleon Sea from Lattice QCD
• Extracting Parton Distribution Functions from Lattice QCD Calculations
• Nucleon structure functions from lattice operator product expansion
• Exclusive processes in position space and the pion distribution amplitude
• A Lattice Calculation of Parton Distributions
• A guide to light-cone PDFs from Lattice QCD: an overview of approaches, techniques and results
• Factorization Theorem Relating Euclidean and Light-Cone Parton Distributions
• One-Loop Matching for Parton Distributions: Non-Singlet Case
• A complete non-perturbative renormalization prescription for quasi-PDFs
• Origin of Difference between $\overline{d}$ and $\overline{u}$ Partons in the Nucleon
• Perturbative Renormalization of quasi-PDFs
• On the Renormalizability of Quasi Parton Distribution Functions
• Renormalization in Large Momentum Effective Theory of Parton Physics
• Deep-inelastic scattering and the operator product expansion in lattice QCD
• Reconstruction of light-cone parton distribution functions from lattice QCD simulations at the physical point
• Pion Valence Quark Distribution from Matrix Element Calculated in Lattice QCD
• Nonperturbative renormalization of nonlocal quark bilinears for quasi-PDFs on the lattice using an auxiliary field
• Pion Valence Structure from Ioffe Time Pseudo-Distributions
• Transversity parton distribution functions from lattice QCD
• Nonperturbative Evolution of Parton Quasi-Distributions
• Updated Lattice Results for Parton Distributions
• First direct lattice-QCD calculation of the $x$-dependence of the pion parton distribution function
• Improved quasi parton distribution through Wilson line renormalization
• Valence parton distribution function of pion from fine lattice
• Unpolarized and helicity generalized parton distributions of the proton within lattice QCD
• Nucleon and pion structure with lattice QCD simulations at physical value of the pion mass
• Matching the Quasi Parton Distribution in a Momentum Subtraction Scheme
• Proton and neutron electromagnetic form factors from lattice QCD
• Pion distribution amplitude from Euclidean correlation functions: Exploring universality and higher-twist effects
• Nucleon axial, tensor and scalar charges and $\sigma$-terms in lattice QCD
• Proton Isovector Helicity Distribution on the Lattice at Physical Pion Mass
• Valence parton distribution of pion from lattice QCD: Approaching continuum
• Power corrections and renormalons in parton quasi-distributions
• Lattice-QCD Calculations of TMD Soft Function Through Large-Momentum Effective Theory
• More On Large-Momentum Effective Theory Approach to Parton Physics
• Reconstructing parton distribution functions from Ioffe time data: from Bayesian methods to Neural Networks
• Moments of Ioffe time parton distribution functions from non-local matrix elements
• A Hybrid Renormalization Scheme for Quasi Light-Front Correlations in Large-Momentum Effective Theory
• Pion valence quark distribution from current-current correlation in lattice QCD
• Systematic uncertainties in parton distribution functions from lattice QCD simulations at the physical point
• Pion generalized parton distribution from lattice QCD
• First Physics Results at the Physical Pion Mass from $N_f=2$ Wilson Twisted Mass Fermions at Maximal Twist
• Parton Distribution Functions from Ioffe time pseudo-distributions
• One-loop evolution of parton pseudo-distribution functions on the lattice
• Low-lying baryon masses using $N_f=2$ twisted mass clover-improved fermions directly at the physical point
• Moments of nucleon generalized parton distributions from lattice QCD simulations at physical pion mass
• Parton Distribution Functions from Ioffe Time Pseudodistributions from Lattice Calculations: Approaching the Physical Point
• Unpolarized isovector quark distribution function from Lattice QCD: A systematic analysis of renormalization and matching
• Gluon quasidistribution function at one loop
• Quark Pseudo-Distributions at Short Distances
• Isovector parton distribution functions of the proton on a superfine lattice
• Renormalization functions for Nf=2 and Nf=4 Twisted Mass fermions
• Generalized Parton Distributions and Pseudo-Distributions
• Model independent determination of the light-cone wave functions for exclusive processes
• Parton distribution functions from reduced Ioffe-time distributions
• Confronting lattice parton distributions with global QCD analysis
• Towards the nucleon hadronic tensor from lattice QCD
• Structure of parton quasi-distributions and their moments
• Parton distribution functions of ${\Delta }^{+}$ on the lattice
• The role of the Euclidean signature in lattice calculations of quasi-distributions and other non-local matrix elements
• Parton distributions from lattice data: the nonsinglet case
• Generalized quasi parton distributions in a diquark spectator model
• New insights on proton structure from lattice QCD: the twist-3 parton distribution function $g_T(x)$
• Finite-volume effects due to spatially non-local operators
• Theory and applications of parton pseudodistributions
• Nonperturbative partonic quasidistributions of the pion from chiral quark models
• $⟨x⟩$ and $⟨x^2⟩$ of the pion PDF from Lattice QCD with $N_f=2+1+1$ dynamical quark flavours
• Lattice QCD evaluation of the Compton amplitude employing the Feynman-Hellmann theorem
• Improvement, generalization, and scheme conversion of Wilson-line operators on the lattice in the auxiliary field approach
• Renormalization of parton quasi-distributions beyond the leading order: spacelike vs. timelike
• Quasi-parton distribution functions: a study in the diquark spectator model
• Partonic quasidistributions in two-dimensional QCD
• The role of zero-mode contributions in the matching for the twist-3 PDFs $e(x)$ and $h_L(x)$
• One-loop matching for the twist-3 parton distribution $g_T(x)$
• Exploring twist-2 GPDs through quasi-distributions in a diquark spectator model
• Fundamental Properties of the Proton in Light-Front Zero Modes
• Renormalization of Wilson-line operators in the presence of nonzero quark masses
• Renormalization Group Analysis of Lattice Theories and Improved Lattice Action. II -- four-dimensional non-abelian SU(N) gauge model
• Nucleon strange electromagnetic form factors
• Partonic quasi-distributions of the proton and pion from transverse-momentum distributions
• Quasi parton distribution functions at NNLO: flavor non-diagonal quark contributions
• Master Integrals for two-loop QCD corrections to Quasi PDFs
• Parton distribution functions from lattice QCD using Bayes-Gauss-Fourier transforms
• Collective charge excitations and the metal-insulator transition in the square lattice Hubbard-Coulomb model
• Quasi Distribution Amplitude of Heavy Quarkonia
• Reconstructing parton densities at large fractional momenta
• Nucleon quasi-Parton Distributions in the large N${}_c$ limit
• Renormalon Effects in Quasi Parton Distributions
• Direct detection of metal-insulator phase transitions using the modified Backus-Gilbert method

Cited by in corpus (41)

• 50 Years of Quantum Chromodynamics
• Snowmass 2021 whitepaper: Proton structure at the precision frontier
• Nucleon Tomography and Generalized Parton Distribution at Physical Pion Mass from Lattice QCD
• Precision Studies of QCD in the Low Energy Domain of the EIC
• The Present and Future of QCD
• Generalized Parton Distributions from Lattice QCD with Asymmetric Momentum Transfer: Unpolarized Quarks
• Continuum-extrapolated NNLO Valence PDF of Pion at the Physical Point
• Nucleon Helicity Generalized Parton Distribution at Physical Pion Mass from Lattice QCD
• Lattice continuum-limit study of nucleon quasi-PDFs
• Transversity GPDs of the proton from lattice QCD
• Moments of proton GPDs from the OPE of nonlocal quark bilinears up to NNLO
• Flavor decomposition of the nucleon unpolarized, helicity and transversity parton distribution functions from lattice QCD simulations
• Unpolarized proton PDF at NNLO from lattice QCD with physical quark masses
• Updated QCD global analysis of single transverse-spin asymmetries I: Extracting $\tilde{H}$, and the role of the Soffer bound and lattice QCD
• Towards the determination of the gluon helicity distribution in the nucleon from lattice quantum chromodynamics
• Positivity and renormalization of parton densities
• Complementarity of experimental and lattice QCD data on pion parton distributions
• First Glimpse into the Kaon Gluon Parton Distribution Using Lattice QCD
• Parton distribution functions beyond leading twist from lattice QCD: The $h_L(x)$ case
• Pion Valence-Quark Generalized Parton Distribution at Physical Pion Mass
• Continuum limit of parton distribution functions from the pseudo-distribution approach on the lattice
• Overview of lattice calculations of the $x$-dependence of PDFs, GPDs and TMDs
• Gluon Parton Distribution of the Nucleon from 2+1+1-Flavor Lattice QCD in the Physical-Continuum Limit
• One-Loop Hybrid Renormalization Matching Kernels for Quasi-Parton Distributions
• Non-singlet quark helicity PDFs of the nucleon from pseudo-distributions
• Generalized parton distributions from the pseudo-distribution approach on the lattice
• Burkhardt-Cottingham-type sum rules for light-cone and quasi-PDFs
• Chiral Perturbation for Large Momentum Effective Field Theory
• Bayesian-Wilson coefficients in lattice QCD computations of valence PDFs and GPDs
• Generalized quasi, Ioffe-time, and pseudo quark distributions of the pion in the Nambu--Jona-Lasinio model
• Mapping Parton Distributions of Hadrons with Lattice QCD
• Non-local Nucleon Matrix Elements in the Rest Frame
• Generalized Parton Distributions from Lattice QCD with Asymmetric Momentum Transfer: Unpolarized Quarks at Nonzero Skewness
• Large-Momentum Effective Theory's Asymptotic Extrapolation vs the Inverse Problem
• A Unified Neural-Network Framework for Nucleon Imaging from Numerical Simulations of QCD
• The Continuum and Leading Twist Limits of Parton Distribution Functions in Lattice QCD
• The transversity parton distribution function of the nucleon using the pseudo-distribution approach
• One-loop Matching Factors for Singlet Quasi-Parton Distribution Functions in the Hybrid-Ratio Scheme
• Towards High-Precision Parton Distributions From Lattice QCD via Distillation
• Light-cone PDFs and GPDs from Lattice QCD
• Unpolarized gluon distribution in the nucleon from lattice quantum chromodynamics