相关论文: Generalized parton distributions in a meson cloud …
A brief overview of the recent activity in the measurement of the elastic electromagnetic proton and neutron form factors is presented. It is discussed how the quality of the data has been greatly improved by performing double polarization…
We present a first calculation of the generalized parton distributions of the photon(both polarized and unpolarized) using overlaps of light-front wave functions at leading order in \alpha and zeroth order in \alpha_s; for non-zero…
We present a physically motivated parametrization of the chiral-even generalized parton distributions in the non-singlet sector obtained from a global analysis using a set of available experimental data. Our analysis is valid in the…
We calculate generalized parton distribution functions in a field theoretic formalism using a covariant Bethe-Salpeter approach for the determination of the bound-state wave function. We describe the procedure in an exact calculation in…
Nucleon form factors at high momentum transfer |t| are treated in the framework of generalized parton distributions (GPD's). The possibility of obtaining information about parton high transverse momentum components by application of GPD's…
It is pointed out that the meson cloud model predicts a substantial polarization of the sea quarks of the nucleon due to interference of $\pi$ and $\rho$ exchanges. This polarization is strongly flavour dependent. The model gives an…
In this talk an introduction to generalized parton distributions is given. Recent developments are shortly reviewed, including non-perturbative calculations, phenomenological aspects and evaluation of higher order perturbative and power…
A method is described for calculating the Generalized Parton Distributions (GPDs) of spin 1/2 hadrons made of composite constituents, in an Impulse Approximation framework. GPDs are obtained from the convolution between the light cone…
We calculate skewed parton distributions $H^I$ of a pion within a non-local NJL model with momentum dependent constituent quark mass $M(k)$. In the forward limit $H^I$ correspond to parton distributions, whereas for $t<0$, $H^I$ is related…
We present a calculation of the generalized parton distributions of the photon when there is non-zero momentum transfer both in the transverse and longitudinal directions. We consider only the contributions when the photon helicity is not…
We recall the physical features of the parton distributions in the quantum statistical approach of the nucleon, which allows to describe simultaneously, unpolarized and polarized Deep Inelastic Scattering data. Some predictions from a…
The nucleon helicity-independent generalized parton distributions (GPDs) of quarks are calculated in the zero skewness case, in the framework of the AdS/QCD model. The present approach is based on a matching procedure of sum rules relating…
We discuss the recent interpretation of quark distribution functions in the plane transverse to the light-cone direction. Such a mapping is model independent and allows one to build multidimensional pictures of the hadron and to develop a…
In the following, the subject of Deep Virtual Compton Scattering on the nucleon and its relation to the recently introduced concept of Generalized Parton Distributions are briefly reviewed. The general theoretical framework and the links…
A simple model is presented for the parton distributions in hadrons. The parton momenta in the hadron rest frame are derived from a spherically symmetric, Gaussian, distribution having a width motivated by the Heisenberg uncertainty…
We present results on the axial and the electromagnetic form factors of the nucleon, as well as, on the first moments of the nucleon generalized parton distributions using maximally twisted mass fermions. We analyze two N_f=2+1+1 ensembles…
The spin structure of the nucleon is studied in a light-cone description of the nucleon where the Fock expansion is truncated to consider only valence quarks. Transverse momentum dependent parton distributions and transverse-spin densities,…
Parametrization of nuclear parton distributions is investigated in the leading order of alpha_s. The parton distributions are provided at Q^2=1 GeV^2 with a number of parameters, which are determined by a chi^2 analysis of the data on…
For an unpolarized target, the generalized parton distribution $H_q(x,0,t)$ is related to the distribution of partons in impact parameter space. The transverse distortion of this distribution for a transversely polarized target is described…
We briefly recall the main physical features of the parton distributions in the quantum statistical picture of the nucleon. Some predictions from a next-to-leading order QCD analysis are successfully compared to recent unpolarized and…