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The meson cloud distributions in $r$-space are extracted from the nucleon electromagnetic and axial form factors which are derived in the perturbative chiral quark model. The theoretical results indicate that the electric charge and axial charge distributions of the three-quark core are the same, the magnetic charge distributions of the meson cloud and three-quark core are more or less in the same region and peak at distances of around 2 $rm GeV^{-1}$, but the axial charge meson cloud distributes mainly inside the three-quark core.
We reconsider the question of electric charge quantization, which leads to the existence of a dark charge nontrivially unified with weak isospin in a novel gauge symmetry, $SU(3)_Cotimes SU(2)_Lotimes U(1)_Yotimes U(1)_N$, where $Y$ and $N$ determine
The unpolarized, helicity and transversity parton distribution functions of the nucleon are studied within a convolution model where the bare nucleon is dressed by its virtual meson cloud. Using light-front time-ordered perturbation theory, the Fock
We use the meson cloud model of the nucleon to calculate distribution functions for $(bar {d} - bar{u})$ and $ bar{d}/bar{u}$ in the proton. Including the effect of the omega meson cloud, with a coupling constant $g_omega^2/4piapprox 8$, allows a reasonably good description of the data.
The axial form factor as well as the axial charge of octet baryons are studied in the perturbative chiral quark model (PCQM) with the quark wave functions predetermined by fitting the theoretical results of the proton charge form factor to experiment
Exact expression is obtained for the differential cross section of elastic electroweak scattering of longitudinal polarized massive Dirac neutrinos with the electric charge and anomalous magnetic moment on a spinless nucleus. This formula contains al