Related papers: New parton distributions in fixed flavour factoriz…
A model for the parton distributions in hadrons is derived from simple physical arguments leading to an analytical expression for the valence distributions. The sea parton distributions arise mainly from pions in hadronic fluctuations.…
A QCD analysis of the world data on inclusive polarized deep inelastic scattering of leptons on nucleons is presented in leading and next-to-leading order. New parameterizations are derived for the quark and gluon distributions and the…
We present next-to-leading-order (NLO) calculations of heavy-quark contributions to deep-inelastic scattering (DIS) structure functions $F_4$ and $F_5$ within the Aivazis--Collins--Olness--Tung (ACOT) scheme, implemented in the open source…
In this contribution we apply the QCD dipole picture combined with $k_T$-factorization to get predictions for deep-inelastic scattering on an onium. Assuming renormalization-group factorization, we get predictions for the $F_2, F_G$ and $R=…
We check the impact of the gluon distribution due to the number of active flavor employed in the calculation of heavy-quark deep-inelastic scattering (DIS) electro-production on the reduced cross section and structure functions determined…
We analyse recent data on the production of forward neutrons in deep inelastic scattering at HERA in the framework of a perturbative QCD description for semi-inclusive processes, which includes fracture functions. Using a model estimate for…
Sets of parton distribution functions (PDFs) of the proton are reported for the leading (LO), next-to-leading (NLO) and next-to-next-to leading order (NNLO) QCD calculations. The parton distribution functions are determined with the…
We present a comprehensive new global QCD analysis of polarized inclusive deep-inelastic scattering, including the latest high-precision data on longitudinal and transverse polarization asymmetries from Jefferson Lab and elsewhere. The…
A simultaneous NLO QCD fit of the parton density functions (PDFs) of the proton and of the strong coupling $\alpha_{S}(M_{Z})$ is presented. The analysis is based on combined H1 and ZEUS inclusive DIS cross section measurements together…
We recall our recent description of quark parton densities of the proton at $Q^2=4 GeV^2$ in terms of Fermi-Dirac distributions parametrized with very few free parameters. We have also proposed some simple assumptions to relate unpolarized…
We study the possibility of intrinsic (non-perturbative) charm in parton distribution functions (PDF) of the proton, within the context of the CT10 next-to-next-to-leading order (NNLO) global analysis. Three models for the intrinsic charm…
We determine at NNLO (3-loop) of QCD the dynamical parton distributions of the nucleon generated radiatively from valencelike positive input distributions at an optimally chosen low resolution scale (Q_0^2<1 GeV^2) by employing the "fixed…
The quantum statistical parton distributions approach proposed more than one decade ago is revisited by considering a larger set of recent and accurate Deep Inelastic Scattering experimental results. It enables us to improve the description…
Measurements of the deep-inelastic scattering (DIS) of leptons and nucleons, $e+p\to e+X$, allow the extraction of Parton Distribution Functions (PDFs) which describe the longitudinal momentum carried by the quarks, anti-quarks and gluons…
Parton distribution functions (PDFs) with QED corrections extracted from the QED$\otimes$QCD DGLAP evolution equations in the framework of "valon" model. Our results for the PDFs with QED corrections in this phenomenological model are in…
The recent theory developments and latest experimental results on heavy-flavour production in Deep Inelastic Scattering and at hadron colliders are summarized. Models of heavy quarkonia production, non-perturbative corrections to…
In the past year, polarized deep inelastic scattering experiments at CERN and SLAC have obtained structure function measurements off proton, neutron and deuteron targets at a level of precision never before achieved. The measurements can be…
At HERA heavy quarks may contribute up to 30% of the structure function $F_2$. The potential of including heavy-quark data in the ZEUS PDF fits is explored, using $D^*$ double differential cross-sections as well as the inclusive quantities…
Parton Distribution Functions (PDFs) model the parton content of the proton. Among the many collaborations which focus on PDF determination, NNPDF pioneered the use of Neural Networks to model the probability of finding partons (quarks and…
We argue that the deep inelastic structure function $F_2^{\gamma p}(x, Q^2)$, regarded as a cross section for virtual $\gamma^*p$ scattering, is hadronic in nature. This implies that its growth is limited by the Froissart bound at high…