184 research outputs found
Helicity-dependent generalized parton distributions for nonzero skewness
We investigate the helicity dependent generalized parton distributions (GPDs)
in momentum as well as transverse position (impact) spaces for up and down
quarks in a proton when the momentum transfer in both the transverse and
longitudinal directions are nonzero. The GPDs are evaluated using the
light-front wavefunctions of a quark-diquark model for nucleon where the
wavefunctions are constructed by the soft-wall AdS/QCD correspondence. We also
express the GPDs in the boost-invariant longitudinal position space.Comment: 13 pages, 10 figures; to appear in Eur. Phys. J. C. arXiv admin note:
text overlap with arXiv:1509.0059
Longitudinal momentum densities in transverse plane for nucleons
We present a study of longitudinal momentum densities ()
in the transverse impact parameter space for and quarks in both
unpolarized and transversely polarized nucleons by taking a two dimensional
Fourier transform of the gravitational form factors with respect to the
momentum transfer in the transverse direction. The gravitational form factors
are obtained by the second moments of GPDs. Here we consider the GPDs of two
different soft-wall models in AdS/QCD correspondence.Comment: 12 pages, 9 figures; text modifie
Nucleon to transition form factors and empirical transverse charge densities
We investigate the nucleon to transition form factors in a soft-wall
AdS/QCD model and a light-front quark-diquark model inspired by AdS/QCD. From
the transition form factors we evaluate the transition charge densities which
influences the nucleon to excitation. Here we consider both the
unpolarized and the transversely polarized cases. The AdS/QCD predictions are
compared with available experimental data and with the results of the global
parameterization, MAID2007.Comment: 9 pages, 5 figures; minor text modified, version to appear in Eur.
Phys. J.
Nucleon and flavor form factors in a light front quark model in AdS/QCD
Using the light front wave functions for the nucleons in a quark model in
AdS/QCD, we calculate the nucleon electromagnetic form factors. The flavor
decompositions of the nucleon form factors are calculated from the GPDs in this
model. We show that the nucleon form factors and their flavor decompositions
calculated in AdS/QCD are in agreement with experimental data.Comment: To appear in Eur. Phys. J. C; The final publication is available at
link.springer.co
Wigner distributions for an electron
We study the Wigner distributions for a physical electron, which reveal the
multidimensional images of the electron. The physical electron is considered as
a composite system of a bare electron and photon. The Wigner distributions for
unpolarized, longitudinally polarized and transversely polarized electron are
presented in transverse momentum plane as well as in impact parameter plane.
The spin-spin correlations between the bare electron and the physical electron
are discussed. We also evaluate all the leading twist generalized transverse
momentum distributions (GTMDs) for electron.Comment: 27 pages, 18 figures, text modified, version accepted in Nuclear
Physics
Transverse charge and magnetization densities in holographic QCD
We present a study of flavor structures of transverse charge and anomalous
magnetization densities for both unpolarized and transversely polarized
nucleons. We consider two different models for the electromagnetic form factors
in holographic QCD. The flavor form factors are obtained by decomposing the
Dirac and Pauli form factors for nucleons using the charge and isospin
symmetry. The results are compared with two standard phenomenological
parametrizations.Comment: minor modifications, some references correcte
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