Related papers: Parton Densities from Collider Data
The generalized parton distributions, introduced nearly a decade ago, have emerged as a universal tool to describe hadrons in terms of quark and gluonic degrees of freedom. They combine the features of form factors, parton densities and…
We review the analysis of polarized structure function data using perturbative QCD at next-to-leading order. We use the most recent experimental data to obtain updated results for polarized parton distributions, first moments and the strong…
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…
By working in QED, we obtain the electron, positron, and photon Parton Distribution Functions (PDFs) of the unpolarised electron at the next-to-leading logarithmic accuracy. The PDFs account for all of the universal effects of initial-state…
Parton distribution functions and hadronic tensors may be computed on a universal quantum computer without many of the complexities that apply to Euclidean lattice calculations. We detail algorithms for computing parton distribution…
Parton densities are obtained from a solution of the extended DGLAP-type evolution equation that includes both QCD and electroweak contributions. The equations are solved using the Parton-Branching (PB) approach, and the evolution is…
We present a critical assessment of what can be learnt from the present data on inclusive polarized DIS. We examine critically some of the simplifying assumptions made in recent analyses and study in detail the question of the determination…
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…
We present new improved parton distributions for the photon. We fit {\bf all} available data on the photon structure function, $F^{\gamma}_{2}(x,Q^2)$, with $Q^2\ge 3$ GeV$^2$, in order to determine the quark distributions. We also pay…
The unpolarized, helicity and transversity parton distribution functions of the nucleon are studied within a convolution model where the bare nucleon is dressed by its virtual meson cloud. Using light-front time-ordered perturbation theory,…
We present new sets of fragmentation functions for charged pions and kaons, both at leading and next-to-leading order. They are fitted to TPC data taken at energy $\sqrt s=29$~GeV and describe excellently a wealth of other $e^+e^-$ data on…
We discuss the statistical properties of parton distributions within the framework of the NNPDF methodology. We present various tests of statistical consistency, in particular that the distribution of results does not depend on the…
I review the current status of the nucleon PDFs determined from global fits with emphasis on the impact of recent experimental data and the remaining theoretical challenges.
A next-to-leading order QCD analysis of spin asymmetries and structure functions in polarized deep inelastic lepton nucleon scattering is presented within the framework of the radiative parton model. A consistent NLO formulation of the…
I discuss the parton distributions in the photon and the constraints coming from the jet production in photoproduction and in photon-photon collisions.
The main goals of `spin physics' are recalled, and some theoretical and phenomenological aspects of longitudinally polarized deep inelastic scattering and other hard processes are reviewed. The spin dependent parton densities of protons and…
The spatial distribution of partons in the proton can be probed in suitable exclusive scattering processes. I report on recent performance estimates for parton imaging at a proposed Electron-Ion Collider.
We calculate the production of high energy photons from Compton and annihilation processes as well as fragmentation off quarks in the parton cascade model. The multiple scattering of partons is seen to lead to a substantial production of…
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…
Parton recombination has been found to be an extremely useful model to understand hadron production at the Relativistic Heavy Ion Collider. It is particularly important to explore its connections with hard processes. This article reviews…