Sea Quarks Contribution to the Nucleon Magnetic Moment and Charge Radius at the Physical Point

Abstract

We report a comprehensive analysis of the light and strange disconnected-sea quarks contribution to the nucleon magnetic moment, charge radius, and the electric and magnetic form factors. The lattice QCD calculation includes ensembles across several lattice volumes and lattice spacings with one of the ensembles at the physical pion mass. We adopt a model-independent extrapolation of the nucleon magnetic moment and the charge radius. We have performed a simultaneous chiral, infinite volume, and continuum extrapolation in a global fit to calculate results in the continuum limit. We find that the combined light and strange disconnected-sea quarks contribution to the nucleon magnetic moment is ${\mu }_M(\text{DI})=-0.022(11)(09){\mu }_N$ and to the nucleon mean square charge radius is $⟨r^2{⟩}_E\text{(DI)}=-0.019(05)(05)$ fm${}^2$ which is about $1/3$ of the difference between the $⟨r_p^2{⟩}_E$ of electron-proton scattering and that of muonic atom and so cannot be ignored in obtaining the proton charge radius in the lattice QCD calculation. The most important outcome of this lattice QCD calculation is that while the combined light-sea and strange quarks contribution to the nucleon magnetic moment is small at about $1\%$, a negative $2.5(9)\%$ contribution to the proton mean square charge radius and a relatively larger positive $16.3(6.1)\%$ contribution to the neutron mean square charge radius come from the sea quarks in the nucleon. For the first time, by performing global fits, we also give predictions of the light and strange disconnected-sea quarks contributions to the nucleon electric and magnetic form factors at the physical point and in the continuum and infinite volume limits in the momentum transfer range of $0\le Q^2\le 0.5$ GeV${}^2$.

arXiv commentPublished Version, 26 pages, 8 figures

References in corpus (33)

• Domain wall QCD with physical quark masses
• Continuum Limit Physics from 2+1 Flavor Domain Wall QCD
• The Proton Radius Puzzle
• Model independent extraction of the proton charge radius from electron scattering
• Extraction of the proton radius from electron-proton scattering data
• Chiral Perturbation Theory Analysis of the Baryon Magnetic Moments
• Nucleon Charges and Electromagnetic Form Factors from 2+1+1-Flavor Lattice QCD
• Nucleon form factors with 2+1 flavor dynamical domain-wall fermions
• $\pi$N and strangeness sigma terms at the physical point with chiral fermions
• Strangeness and charmness content of nucleon from overlap fermions on 2+1-flavor domain-wall fermion configurations
• Nucleon electromagnetic form factors from lattice QCD using a nearly physical pion mass
• Nucleon Masses and Magnetic Moments in a Finite Volume
• Model independent extraction of the proton magnetic radius from electron scattering
• Nucleon Electromagnetic Form Factors from Lattice QCD using 2+1 Flavor Domain Wall Fermions on Fine Lattices and Chiral Perturbation Theory
• Disconnected quark loop contributions to nucleon observables in lattice QCD
• Overlap Valence on 2+1 Flavor Domain Wall Fermion Configurations with Deflation and Low-mode Substitution
• Nucleon electromagnetic form factors in twisted mass lattice QCD
• High-precision calculation of the strange nucleon electromagnetic form factors
• Nucleon electromagnetic form factors in two-flavour QCD
• Strange magnetism in the nucleon
• Strange Quark Magnetic Moment of the Nucleon at Physical Point
• Strange chiral nucleon form factors
• Lattice Calculation of Nucleon Isovector Axial Charge with Improved Currents
• Review of experimental and theoretical status of the proton radius puzzle
• Stochastic method with low mode substitution for nucleon isovector matrix elements
• Neutral Weak Form Factors of Proton and Neutron
• Lattice Results on the Connected Neutron Charge Radius
• Finite Volume Effects on the Extraction of Form Factors at Zero Momentum
• Novel applications of Lattice QCD: Parton distribution functions, proton charge radius and neutron electric dipole moment
• Lattice Calculations of Nucleon Electromagnetic Form Factors at Large Momentum Transfer
• Position space method for the nucleon magnetic moment in lattice QCD
• Nucleon electromagnetic form factors and axial charge from CLS $N_{\mathrm{f}}=2+1$ ensembles
• Nucleon electromagnetic and axial form factors with N${}_f$=2 twisted mass fermions at the physical point

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• Proton and neutron electromagnetic form factors from lattice QCD
• Precision Studies of QCD in the Low Energy Domain of the EIC
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• Constraints on charm-anticharm asymmetry in the nucleon from lattice QCD
• Nucleon strange electromagnetic form factors
• Nonperturbative strange-quark sea from lattice QCD, light-front holography, and meson-baryon fluctuation models
• Strange electromagnetic form factors of the nucleon with $N_f=2+1$ $\mathcal{O}(a)$-improved Wilson fermions
• RI/MOM and RI/SMOM renormalization of overlap quark bilinears on domain wall fermion configurations
• Strange nucleon electromagnetic form factors from lattice QCD
• Strange form factors of nucleon with nonlocal chiral effective Lagrangian
• Generalized parton distributions of sea quarks in the proton from nonlocal chiral effective theory
• The proton radius puzzle
• Measurement of the total neutron scattering cross section ratios of noble gases of natural isotopic composition using a pulsed neutron beam
• Sea quark contributions to nucleon electromagnetic form factors with the nonlocal chiral effective Lagrangian
• Contributions to the nucleon form factors from bubble and tadpole diagrams
• Sea quark contributions to the electromagnetic form factors of $\Sigma$ hyperons