We provide an assessment of the impact of parton distributions on the determination of LHC processes, and of the accuracy with which parton distribution functions (PDFs) can be extracted from data, in particular from current and forthcoming HERA experiments. We give an overview of reference LHC processes and their associated PDF uncertainties, and study in detail W and Z production at the LHC. ...

The non-perturbative parton distributions in hadrons are derived from simple physical arguments resulting in an analytical expression for the valence parton distributions. The sea partons arise mainly from pions in hadronic fluctuations. The model gives new insights and a good description of structure function data. Hard processes involving hadrons are calculated by folding perturbative QCD mat...

To study heavy ion collisions at energies available from the Relativistic Heavy Ion Collider ~RHIC!, we have developed a multiphase transport model that includes both initial partonic and final hadronic interactions. Specifically, the Zhang’s parton cascade ~ZPC! model, which uses as input the parton distribution from the heavy ion jet interaction generator ~HIJING! model, is extended to includ...

An alternative calculation of the lowest order electroweak radiative corrections (EWC) to the single W-boson production in hadron-hadron collision in the framework of the quark parton model without any absorption of the collinear quark singularity into the parton distributions is carried out. Numerical analysis under Tevatron and LHC kinematic conditions is performed.

Recent experimental measurements of the Gottfried Sum Rule, and pp and pD Drell-Yan processes, suggest significant violation of flavor symmetry in the proton sea. This interpretation rests on the assumption of parton charge symmetry. Our model calculations suggest charge symmetry violation [CSV] for parton valence distributions of a few percent. Precision measurements of structure functions in ...

We study in detail the kinematics of semileptonic M l3 (M → M ′ lν) decay, considering only the new models preserving all the gauge symmetries of the Standard Model (SM), and assuming that neutrinos are massless and left-handed as in the SM. And we present a brief review of the recent theoretical progress on model independent constraints on the form factors of M l3 decays using dispersion relat...

To study heavy ion collisions at energies available from the Relativistic Heavy Ion Collider, we have developed a multi-phase transport model that includes both initial partonic and final hadronic interactions. Specifically, the parton cascade model ZPC, which uses as input the parton distribution from the HIJING model, is extended to include the quark-gluon to hadronic matter transition and al...

The alternative to the standard formulation of the quark-parton model is proposed. Our approach is based on the solution of the master equations relating the structure and distribution functions, which consistently takes into account the intrinsic quark motion in contradistinction to the standard infinite momentum approach, in which this motion is latently suppressed. The model well reproduces ...

Gluon distributions in the carbon and tin nuclei are investigated by using a Q 2 rescaling model with parton recombination effects. We obtain strong shadowings in the small x region due to the recombinations. The ratio G A (x)/G N (x) in the medium x region is typically 0.9 for medium size nuclei. At large x, the ratio becomes large due to gluon fusions from different nucleons. Comparisons with...

We compute amplitude of deeply virtual Compton scattering in the parton model. We found that the amplitude up to the accuracy O(1/Q) depends on new skewed par-ton distributions (SPD's). These additional contributions make the DVCS amplitude explicitly transverse.