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The relativistic constituent quark model of low-energy quantum chromodynamics is found to yield a consistent picture of the electroweak structure of the nucleons. Notably, the electromagnetic and axial form factors of both the proton and the neutron can be described in close agreement with existing experimental data in the domain of low to moderate momentum transfers. For the theory it is mandatory to respect Poincare invariance and to fulfill additional conditions like charge normalization. Here we present covariant predictions of the one-gluon-exchange and Goldstone-boson-exchange constituent quark models for the electroweak form factors of the nucleons and give a critical discussion of the results in view of the point-form spectator model employed for the electromagnetic and axial current operators.
We discuss electromagnetic currents in the point-form formulation of relativistic quantum mechanics. The construction is along a spectator model and implies that only one quark is explicitly coupled to the photon, but nevertheless many-body contribut
We construct spin-improved holographic light-front wavefunctions for the nucleons (viewed as quark-diquark systems) and use them to successfully predict their electromagnetic Sachs form factors, their electromagnetic charge radii, as well as the axia
Elastic electromagnetic form factors of nucleons are investigated both for the time-like and the space-like momentums by using the unsubtracted dispersion relation with QCD constraints. It is shown that the calculated form factors reproduce the exper
To obtain further information on the geometric shape of the nucleon, the proton charge form factor is decomposed into two terms, which are connected respectively with a spherically symmetric and an intrinsic quadrupole part of the protons charge dens
The nucleon electromagnetic form factors are calculated in light cone QCD sum rules framework using the most general form of the nucleon interpolating current. Using two forms of the distribution amplitudes (DAs), predictions for the form factors are