相关论文: New Parton Distribution Functions for the Photon
Using differential cross-section data of inclusive $W$ and $Z/\gamma^\ast$ boson production and of their production in association with jets, and differential cross-section data of top-quark pair production in the lepton + jets and dilepton…
We argue that existing measurements of ep collisions at HERA --in which an energetic photon is made via a QED `Compton' subprocess-- can provide rather detailed information on the photonic parton density of the proton. This function and its…
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…
The structure of the general solution of the inhomogeneous evolution equations allows the separation of a photon structure function into perturbative (``anomalous") and non-perturbative contributions. The former part is fully calculable,…
This article gives an overview over recent results on quark and gluon helicity distributions obtained in deep inelastic lepton nucleon scattering and proton proton interactions. Future experimental programs to study the nucleon structure…
Recent progresses of the proton structure measurements and determination of parton distribution functions by $ep$ collisions at HERA are introduced.
We review the latest information that is available about the parton distributions of the proton, paying particular attention to the determination of the gluon. We briefly describe the various processes that have been advocated to be a…
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. The $Q^2$-dependence of the spin…
Reliable knowledge of parton distributions at large x is crucial for many searches for new physics signals in the next generation of collider experiments. Although these are generally well determined in the small and medium x range, it has…
We use an s-channel picture of hard hadronic collisions to investigate the parton distribution function for quarks at small momentum fraction x, which corresponds to very high energy scattering. We study the renormalized quark distribution…
We study the production of a large-pT photon in association with a jet in proton-proton collisions. We examine the sensitivity of the jet rapidity distribution to the gluon distribution function in the proton. We then assess the sensitivity…
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.…
The theoretical framework for a next-to-leading order QCD analysis of the spin-dependent parton densities Delta f^{gamma}(x,Q^2) of the longitudinally polarized photon and of its structure function g_1^{gamma}(x,Q^2) is reviewed in some…
We re\,examine the theory of hadronic photon-nucleon interactions at the quark-gluon level. The possibility of multiple parton collisions in a single photon-nucleon collision requires an eikonal treatment of the high-energy scattering…
We analyze the capability of prompt photon production in pp and pp(bar) collisions to constrain the gluon distribution of the proton, considering data from fixed-target experiments as well as collider measurements. Combined fits are…
The current status of global QCD analysis of parton distribution functions of the nucleon is reviewed. Recent progress made in determining various features of the parton structure of the nucleon, as well as outstanding open questions are…
This paper presents an analysis at next-to-next-to-leading order in the theory of quantum chromodynamics for the determination of a new set of proton parton distribution functions using diverse measurements in $pp$ collisions at $\sqrt{s} =…
New measurements of dijet photoproduction at HERA provide information on the gluon density in the photon and on its quark densities at high x_gamma and high factorisation scales.
We discuss two topics in this talk. One is a brief overview of nuclear parton distributions, and the other is SU(2)-flavor-symmetry breaking in {\it nuclear} antiquark distributions. First, we show that nuclear structure functions…
Study of parton distribution functions (PDFs) has led to a finer cognisance of the structure of partons in hadrons and the proton structure functions in deep inelastic scattering (DIS). PDFs are instrumental in predicting results for most…