On Nucleon Electromagnetic Form Factors

Abstract

A Poincare' covariant Faddeev equation, which describes baryons as composites of confined-quarks and -nonpointlike-diquarks, is solved to obtain masses and Faddeev amplitudes for the nucleon and Delta. The amplitudes are a component of a nucleon-photon vertex that automatically fulfills the Ward-Takahashi identity for on-shell nucleons. These elements are sufficient for the calculation of a quark core contribution to the nucleons' electromagnetic form factors. An accurate description of the static properties is not possible with the core alone but the error is uniformly reduced by the incorporation of meson-loop contributions. Such contributions to form factors are noticeable for Q^2 < ~2 GeV^2 but vanish with increasing momentum transfer. Hence, larger Q^2 experiments probe the quark core. The calculated behaviour of G_E^p(Q^2)/G_M^p(Q^2) on Q^2 \in [2,6] GeV^2 agrees with that inferred from polarisation transfer data. Moreover, \sqrt{Q^2} F_2(Q^2)/F_1(Q^2) is approximately constant on this domain. These outcomes result from correlations in the proton's amplitude.

31 pages, 7 figures, 5 tables

References in corpus (5)

• Precision Rosenbluth measurement of the proton elastic form factors
• Electromagnetic properties of diquarks
• Quark propagator in Landau and Laplacian gauges with overlap fermions
• On the complexion of pseudoscalar mesons
• Baryons as Relativistic Bound States of Quark and Diquark

Cited by in corpus (49)

• Infrared Properties of QCD from Dyson-Schwinger equations
• Baryons as relativistic three-quark bound states
• Nucleon electromagnetic form factors
• Hadron Properties and Dyson-Schwinger Equations
• Magnetic moments of heavy baryons in the relativistic three-quark model
• Aspects of Hadron Physics
• Diquark Correlations in Hadron Physics: Origin, Impact and Evidence
• Survey of nucleon electromagnetic form factors
• On unifying the description of meson and baryon properties
• Nucleon electromagnetic form factors from the covariant Faddeev equation
• Nucleon and $\Delta$ elastic and transition form factors
• Measurement of the proton electric to magnetic form factor ratio from \vec ^1H(\vec e, e'p)
• QCD modeling of hadron physics
• Extraction and Interpretation of gamma N --> Delta Form Factors within a Dynamical Model
• Sigma Terms of Light-Quark Hadrons
• Light baryon magnetic moments and N -> Delta gamma transition in a Lorentz covariant chiral quark approach
• Semileptonic decays of the light J(P)=1/2(+) ground state baryon octet
• Quark-gluon vertex dressing and meson masses beyond ladder-rainbow truncation
• Phase diagram of neutral quark matter in nonlocal chiral quark models
• Mind the gap
• Aspects of the confinement mechanism in Coulomb-gauge QCD
• Chiral extrapolation of octet-baryon charge radii
• A covariant view on the nucleons' quark core
• Hadron structure at low Q^2
• Schwinger functions and light-quark bound states
• Dissecting nucleon transition electromagnetic form factors
• Matrix algorithms for solving (in)homogeneous bound state equations
• Nucleon Compton scattering in the Dyson-Schwinger approach
• Delta-baryon mass in a covariant Faddeev approach
• Nucleon axial-vector and pseudoscalar form factors, and PCAC relations
• On Nucleon Electromagnetic Form Factors: A Pre'cis
• New Perspective on Hybrid Mesons
• Unified description of hadron-photon and hadron-meson scattering in the Dyson-Schwinger approach
• Current quark mass dependence of nucleon magnetic moments and radii
• Light-quarkonium spectra and orbital-angular-momentum decomposition in a Bethe-Salpeter-equation approach
• Composition of low-lying $\mathbf{J}={\frac{3}{2}}^{\pm }\mathbf{\Delta }$-baryons
• Consequences Of Fully Dressing Quark-Gluon Vertex Function With Two-Point Gluon Lines
• Theory and Phenomenology of Hadrons
• Lorentz Harmonics, Squeeze Harmonics, and their Physical Applications
• The mass of the nucleon in a chiral quark-diquark model
• Hadron properties from QCD bound-state equations: A status report
• Meson spectroscopy and properties using Dyson-Schwinger equations
• $\Delta$-baryon axialvector and pseudoscalar form factors, and associated PCAC relations
• Nucleon magnetic form factors with non-local chiral effective Lagrangian
• Investigating the internal structure of $X(6900)$ in the $2J/\psi$ decay channel
• Study on the Form Factors at Effective Vertices of Diqarks Interacting with Gauge Bosons
• S- and D-wave vector charmonia
• Partial-wave decomposition of the Faddeev amplitude of a Poincaré-invariant three-fermion bound state
• Integration of Dirac's Efforts to construct Lorentz-covariant Quantum Mechanics