Related papers: Low-$Q^{2}$ nucleon structure from an infrared-saf…
A novel approach for describing the evolution of nucleon structure from the low-$Q^2$ regime to the high-$Q^2$ asymptotic region is proposed. This infrared-safe scheme modifies the parton distribution evolution equations to incorporate the…
We employ the maximum entropy method to extract the valence quark distributions of the neutron at a low scale, \( Q_0^2 \). At this initial scale, the neutron is defined to contain only three valence quarks, with no contributions from sea…
This review deals with the structure of hadrons, strongly interacting many-body systems consisting of quarks and gluons. These systems have a size of about 1 fm, which shows up in scattering experiments at low momentum transfers $Q$ in the…
We report on the low and moderate Q^2 nucleon spin structure measurements done at Jefferson Lab, examining specifically the inclusive program. We discuss what the data teach us about quark confinement and the emergence of the effective…
At a low resolution scale with $Q^2={\mu}^2$ corresponding to the nucleon bound state; deep inelastic unpolarized structure functions $F_1(x,{\mu}^2)$ and $F_2(x,{\mu}^2)$ are derived with correct support using the symmetric part of the…
We develop a non-perturbative model for valence parton distribution functions (PDFs) based on the mean field interactions of valence quarks in the nucleonic interior. The main motivation for the model is to obtain a mean field description…
In the semiclassical approach, inclusive and diffractive quark and gluon distributions are expressed in terms of correlation functions of Wilson loops. Each Wilson loop integrates the colour field strength in the area between the…
The description of the internal structure of hadrons is one of the main goal of QCD. At moderate energy scales, the hadronic representation succeeds to the partonic description, rendering challenging the description of the dynamics of…
We construct a simple two-phase model of the nucleon structure functions valid for both small and large Q^2 and in the broad range of Bjorken x. The model incorporates hadron dominance at small x and Q^2 and parton model at large Q^2. The…
Heavy quark parton distribution functions (PDFs) play an important role in several Standard Model and New Physics processes. Most analyses rely on the assumption that the charm and bottom PDFs are generated perturbatively by gluon splitting…
The pion structure function is investigated in a simple model, where the pion and its constituent quark fields are coupled through the simplest pseudoscalar coupling. The imaginary part of the forward gamma* pi -> gamma* pi scattering…
A nonsinglet QCD analysis of neutrino-nucleon structure function is performed based on all the data for charged current neutrino-nucleon deep inelastic scattering (DIS) corresponds to NLO and NNLO approximations, with taking into account…
Low and high energy properties of the pion are reviewed in the framework of chiral quark models. Particular emphasis is put on the simplest version of the SU(2) NJL model as prototype. The role of gauge invariance in this kind of…
A whole class of non-perturbative QCD studies, e.g. the instanton models, chiral quark models, etc. indicates that the effective degrees of freedom for the physics in the low Q^(2) < 1 GeV^(2) region could be the constituent quarks (CQs)…
We present an improved model on neutrino- and electron-nucleon scattering cross sections using effective leading order PDFs with a new scaling variable xi_w. Non-perturbative QCD effects at low Q^2 are separately treated for u and d valence…
Nuclear effects in deep inelastic scattering at low$-x$ are phenomenologically described changing the typical dynamical and/or kinematical scales characterizing the free nucleon case. In a holographic approach, this rescaling is an…
We demonstrate that to a very good approximation the scale-evolution of the intrinsic heavy quark content of the nucleon is governed by non-singlet evolution equations. This allows us to analyze the intrinsic heavy quark distributions…
New Results on the measurement of the proton structure function F_2(x,Q^2) are reported for momentum transfers squared Q^2 >= 1.5 GeV^2 and Bjorken x >= 3.5 10^{-5} using data collected by the HERA experiments H1 and ZEUS in 1994. F_2…
Heavy quark parton distribution functions (PDFs) play an important role in several Standard Model and New Physics processes. Most PDF analyses rely on the assumption that the charm and bottom PDFs are generated perturbatively by gluon…
We present a model description of the nucleon valence structure function applicable over the entire region of the Bjorken variable x, and above moderate values of Q**2 (> 1 GeV**2). We stress the importance of describing the complete…