Related papers: A model for parton distributions in hadrons
Parton distribution functions (DFs) have long been recognised as key measures of hadron structure. Today, theoretical prediction of such DFs is becoming possible using diverse methods for continuum and lattice analyses of strong interaction…
We present an extensive study on generalized parton distributions of pions. In particular, we present the results for the pion-photon transition distribution amplitudes in the Nambu - Jona-Lasinio model. We discuss the phenomenology of such…
Measurements of the diffractive structure function, $F_2^D$, of the proton at HERA are used to extract the partonic structure of the Pomeron. Regge Factorization is tested and is found to describe well the existing data within the selected…
Based on quantum fluctuations in momentum and of the proton into meson-baryon pairs, we develop a physical model for the non-perturbative x-shape of parton density functions in the proton. The model describes the proton structure function…
We show how some parton distribution functions related to the transverse spin of nucleons can be extracted point by point from combinations of proton and deuteron observables. In particular, we present a determination of the valence and sea…
Generalized parton distributions (GPDs) are studied at the hadronic (nonperturbative) scale within different assumptions based on a relativistic constituent quark model. In particular, by means of a meson-cloud model we investigate the role…
We give an overview of the theory for generalized parton distributions. Topics covered are their general properties and physical interpretation, the possibility to explore the three-dimensional structure of hadrons at parton level, their…
An algebraic Ansatz for the proton's Poincar\'e-covariant wave function, which includes both scalar and pseudovector diquark correlations, is used to calculate proton valence, sea, and glue distribution functions (DFs). Regarding…
The rates of multiparton collisions in high energy hadronic interactions provide information on the typical transverse distances between partons in the hadron structure. The different configurations of the hadron in transverse space are, on…
Generalized parton distributions have been introduced in recent years as a suitable theoretical tool to study the structure of the nucleon. Unifying the concepts of parton distributions and hadronic form factors, they provide a…
Through explicit examples we show that twist-4 parton distributions have no parton interpretation in the sense that parton or partons inside a hadron can carry the momentum fraction $x$ of the hadron with $x >1$ or $x<-1$. The studied…
Inclusive distributions of soft production of mesons in hadronic collisions are calculated in the valon-recombination model. The new determination of the valon distributions from hard scattering data makes possible a tightly interrelated…
Moments of the generalized parton distributions of the nucleon, calculated with a mixed action of domain wall valence quarks and asqtad staggered sea quarks, are presented for pion masses extending down to 359 MeV. Results for the moments…
We present parton distribution functions which include a quantitative estimate of its uncertainties. The parton distribution functions are optimized with respect to deep inelastic proton data, expressing the uncertainties as a density…
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…
The first measurement of diffractive processes in deep inelastic scattering at the HERA collider is analysed in terms of a "soft" pomeron exchange model. The partonic structure of the pomeron which emerges in this picture is determined…
We compare the parton distributions deduced in the framework of a quantum statistical approach for both the longitudinal and transverse degrees of freedom with the unpolarized distributions measured at Hera and with the polarized ones…
We calculated the polarized parton distributions in leading order approximation in QCD from valon model. Polarized structure function of the nucleon are analyzed in the polarized valon model in which a nucleon is assumed to be a bound state…
A review of the theoretical activity in Italy in the research field of Hadronic Physics is given. Specific focus is put on phenomenological models based on the effective degrees of freedom of constituent quarks, on parton distributions in…
I discuss our current understanding of parton distributions. I begin with the underlying theoretical framework, and the way in which different data sets constrain different partons, highlighting recent developments. The methods of examining…