Related papers: Nucleon form factors from a covariant quark core: …
The inclusion of two-body exchange currents in the constituent quark model leads to several new relations between the electromagnetic form factors of the nucleon and Delta(1232). These are:(i) the neutron charge form factor can be expressed…
We calculate electric and magnetic form factors of protons and neutrons in quenched Monte Carlo lattice QCD on a $16^3\times 24$ lattice at $\beta = 6.0$ using Wilson fermions. We employ a method which characterizes one of the nucleon…
Recent improvements of the hard scattering picture for the large $p_{\perp}$ behaviour of electromagnetic form factors, namely the inclusion of both Sudakov corrections and intrinsic transverse momentum dependence of the hadronic wave…
A covariant quark model, based both on the spectator formalism and on vector meson dominance, and previously calibrated by the physical data, is here extended to the unphysical region of the lattice data by means of one single extra…
The explicit expressions for the electric, magnetic, axial and induced pseudoscalar form factors of the nucleons are derived in the {\it ab initio} quantized Skyrme model. The canonical quantization procedure ensures the existence of stable…
The reaction of the elastic electron-deuteron scattering at high momentum transfer is investigated within the Bethe-Salpeter approach. The relativistic covariant Graz II separable kernel of nucleon-nucleon interactions is used to analyze…
The charge, magnetic and quadrupole form factors of vector mesons and the charge form factor of pseudo-scalar mesons are calculated in quenched lattice QCD. The charge radii and magnetic moments are derived. The quark sector contributions…
The nucleon form factors of the energy-momentum tensor are studied in the large-Nc limit in the framework of the chiral quark-soliton model.
Moments of unpolarized, helicity, and transversity distributions, electromagnetic form factors, and generalized form factors of the nucleon are presented from a preliminary analysis of lattice results using pion masses down to 359 MeV. The…
Based on the recent, high precision data for elastic electron scattering from protons and deuterons, at relatively large momentum transfer $Q^2$, we determine the neutron electric form factor up to $Q^2=3.5$ GeV$^2$. The values obtained…
A confining, symmetry-preserving, Dyson-Schwinger equation treatment of a vector-vector contact interaction is used to formulate Faddeev equations for the nucleon and Delta-baryon in which the kernel involves dynamical dressed-quark…
Inclusive 3He(e,e') and exclusive 3He(e,e'n) processes with polarized electrons and 3He have been theoretically analyzed and values for the magnetic and electric neutron form factors have been extracted. In both cases the form factor values…
The parity violation programs at MIT-Bates, Jefferson Lab and Mainz are presently focused on developing a better understanding of the sea-quark contributions to the vector matrix elements of nucleon structure. The success of these programs…
We analyze commonly used expressions for computing the nucleon electric dipole form factors (EDFF) $F_3$ and moments (EDM) on a lattice and find that they lead to spurious contributions from the Pauli form factor $F_2$ due to inadequate…
We present a study of the electromagnetic structure of the nucleons with constituent quark models in the framework of relativistic quantum mechanics. In particular, we address the construction of spectator-model currents in the instant and…
Accessing hadronic form factors at large momentum transfers has traditionally presented a challenge for lattice QCD simulations. Here we demonstrate how a novel implementation of the Feynman-Hellmann method can be employed to calculate…
We study the instanton contribution to the proton and neutron electric form factors. Using the single instanton approximation, we perform the calculations in a mixed time-momentum representation in order to obtain the form factors directly…
A unified set of predictions for pion and kaon elastic electromagnetic and gravitational form factors is obtained using a symmetry-preserving truncation of each relevant quantum field equation. A key part of the study is a description of…
The electromagnetic form factors of light and heavy pseudoscalar mesons are calculated within two covariant constituent-quark models, a light-front and a dispersion relation approach. We investigate the details and physical origins of the…
The relativistic version of finite-range-regularisation is proposed. The covariant regulator is generated from the nonlocal Lagrangian. This nonlocal interaction is gauge invariant and is applied to study the nucleon electromagnetic form…