相关论文: Flavor analysis of nucleon electromagnetic form fa…
I discuss a two-component model of nucleon form factors in which the external photon couples both to an intrinsic three-quark structure and to a meson cloud via vector-meson dominance, and present a simultaneous analysis of the…
A dressed-quark core contribution to nucleon electromagnetic form factors is calculated. It is defined by the solution of a Poincare' covariant Faddeev equation in which dressed-quarks provide the elementary degree of freedom and…
In light of the improved precision of the experimental measurements and enormous theoretical progress, the nucleon form factors have been evaluated with an aim to understand how the static properties and dynamical behavior of nucleons…
We investigate the electromagnetic form factors of nucleons within a simple relativistic quark spectator-diquark model using the light-cone formalism. Melosh rotations are applied to both quark and vector diquark. It is shown that the…
We present results for the electromagnetic form factors of the proton and neutron computed on the Coordinated Lattice Simulations (CLS) ensembles with $N_f = 2 + 1$ flavors of $\mathcal{O}(a)$-improved Wilson fermions and an…
Results for the proton and neutron electric and magnetic form factors as well as the nucleon axial form factor are presented for constituent quark models, based on either one-gluon-exchange and Goldstone-boson-exchange dynamics. The…
We present the recent high-statistics calculations of the nucleon electromagnetic form factors with fully dynamical domain wall fermions on the 32^3x64 lattices generated by the RBC and UKQCD collaborations, with pion masses at roughly 297…
We present results from the QCDSF/UKQCD collaboration for hyperon electromagnetic form factors and axial charges obtained from simulations using Nf=2+1 flavours of O(a)-improved Wilson fermions. We also consider matrix elements relevant for…
We present analytic parametrizations for the $\gamma^\ast N \to N(1440)$ form factors derived from light-front holography in leading twist approximation. The new parametrizations describe the electromagnetic form factors using analytic…
We study the nucleon electromagnetic form factors in a quark-gluon core model framework, which can be viewed as an extension of the Isgur-Karl model of baryons. Using this picture we derive nucleon electromagnetic dipole form factors at low…
The separate quark flavour contributions to the pion and kaon valence quark distribution functions are studied, along with the corresponding electromagnetic form factors in the space-like region. The calculations are made using the solution…
We use a diquark model of the nucleon to calculate the electromagnetic form factors of the nucleon described as a scalar and axialvector diquark bound state. We provide an analysis of the zero-mode contribution in the diquark model. We find…
We analyze the electromagnetic form factors of the nucleon to fourth order in relativistic baryon chiral perturbation theory. We employ the recently proposed infrared regularization scheme and show that the convergence of the chiral…
Electromagnetic form factors of the nucleon from relativistic quark models are analyzed: results from null-plane projection of the Feynman triangle diagram are compared with a Bakamjian-Thomas model. The magnetic form factors of the models…
We utilize a light-front relativistic quark model (LF RQM) to predict the 3q core contribution to the electroexcitation amplitudes for the Delta(1232)P33, N(1440)P11, N(1520)D13, and N(1535)S11 up to Q2= 12GeV2. The parameters of the model…
We present results on the isoscalar form factors including the disconnected contributions, as well as on the strange and charm quark form factors. Using previous results on the isovector form factors, we determine the flavor decomposition…
We compute electroweak form factors of the nucleon and photon transition form factors of non-strange baryon resonances up to the third resonance region in a model with instanton-induced interaction. The calculation is based on the…
The electromagnetic form factors of the nucleon, in the space-like region, are determined from three-point function Finite Energy QCD Sum Rules. The QCD calculation is performed to leading order in perturbation theory in the chiral limit,…
We present the proton and neutron vector form factors in a convenient parametric form that is optimized for momentum transfers $\lesssim$ few GeV$^2$. The form factors are determined from a global fit to electron scattering data and precise…
We study the nucleon electromagnetic (EM) form factors in symmetric nuclear matter as well as in vacuum within a light-front approach using the in-medium inputs calculated by the quark-meson coupling model. The same in-medium quark…