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Related papers: Polarized Parton Distributions in the Valon Model

200 papers

We present a new next-to-leading order QCD analysis of the world data on inclusive polarized deep inelastic lepton-nucleon scattering adding to the old set of data the final SMC results, the HERMES proton and very recent SLAC/E155 deuteron…

High Energy Physics - Phenomenology · Physics 2009-10-31 Elliot Leader , Alexsander V. Sidorov , Dimiter B. Stamenov

We present the polarized parton distribution functions from a QCD analysis of the worldwide polarized deep inelastic scattering data, based on the dynamical parton distribution model. All the sea quarks and gluons are dynamically generated…

High Energy Physics - Phenomenology · Physics 2022-11-23 Chengdong Han , Gang Xie , Rong Wang , Xurong Chen

We show that the naive positivity conditions on polarized parton distributions which follow from their probabilistic interpretation in the naive parton model are reproduced in perturbative QCD at the leading log level if the quark and gluon…

High Energy Physics - Phenomenology · Physics 2009-10-31 Stefano Forte , Guido Altarelli , Giovanni Ridolfi

Parametrization of nuclear parton distributions is investigated in the leading order of alpha_s. The parton distributions are provided at Q^2=1 GeV^2 with a number of parameters, which are determined by a chi^2 analysis of the data on…

High Energy Physics - Phenomenology · Physics 2009-11-07 M. Hirai , S. Kumano , M. Miyama

We extend the QCD Parton Model analysis using a factorized nuclear structure model incorporating individual nucleons and pairs of correlated nucleons. Our analysis of high-energy data from lepton Deep-Inelastic Scattering, Drell-Yan and W/Z…

We discuss the bounds on polarized parton distributions which follow from their definition in terms of cross section asymmetries. We spell out how the bounds obtained in the naive parton model can be derived within perturbative QCD at…

High Energy Physics - Phenomenology · Physics 2023-12-14 Guido Altarelli , Stefano Forte , Giovanni Ridolfi

We present a measurement of semi-inclusive spin asymmetries for positively and negatively charged hadrons from deep inelastic scattering of polarised muons on polarised protons and deuterons in the range $0.003<x<0.7$ and $Q^2>$1 GeV$^2$.…

High Energy Physics - Experiment · Physics 2015-06-25 Spin Muon Collaboration

QCD motivated polarized parton distributions, evolved directly in $x$-space, are used to predict rates for prompt photon production at RHIC centre of mass energies. Various scenarios for the polarized gluon distributions are considered and…

High Energy Physics - Phenomenology · Physics 2009-09-25 L. E. Gordon

Next-to-leading order approximation of the quark helicity distributions are used in the frame work of polarized valon model. The flavor-asymmetry in the light-quark sea of the nucleon can be obtained from the contributions of unbroken sea…

High Energy Physics - Phenomenology · Physics 2009-11-11 A. Mirjalili , S. Atashbar Tehrani , Ali N. Khorramian

We review the calculation of moments of both the polarized and unpolarized parton distribution functions of the nucleon in lattice QCD, and in particular their extrapolation to the physical region. We also discuss the reconstruction of the…

High Energy Physics - Lattice · Physics 2008-11-26 W. Detmold , W. Melnitchouk , A. W. Thomas

Starting from Martin, Roberts and Stirling fit for unpolarized deep inelastic structure functions and using the newest experimental data on spin asymmetries we get a fit which provides polarized quark distributions. We analyze the behaviour…

High Energy Physics - Phenomenology · Physics 2014-11-17 J. Bartelski , S. Tatur

At large N_c the nucleon can be viewed as a soliton of the effective chiral lagrangian. This picture of nucleons allows a consistent nonperturbative calculation of the leading-twist parton distributions at a low normalization point. We…

High Energy Physics - Phenomenology · Physics 2009-10-28 D. Diakonov , V. Petrov , P. Pobylitsa , M. Polyakov , C. Weiss

We use detailed balance for a hadron composed of quark and gluon Fock states to obtain parton distributions in the proton and pion on the basis of a simple statistical model.

High Energy Physics - Phenomenology · Physics 2008-11-26 Mary Alberg , Ernest M. Henley

Parton distribution functions (DFs) are defining expressions of hadron structure. Exploiting the role of effective charges in quantum chromodynamics, an algebraic scheme is described which, given any hadron's valence parton DFs at the…

High Energy Physics - Phenomenology · Physics 2023-06-07 Pei-Lin Yin , Yin-Zhen. XuID , Zhu-Fang Cui , Craig D. Roberts , José Rodríguez-Quintero

Based on a simple model which is compatible with the idea of the static quark model and the parton model, the polarized structure functions of proton and deuteron, two-spin asymmetries of $\pi ^0$ in polarized $pp$ reactions and inelastic…

High Energy Physics - Phenomenology · Physics 2007-05-23 Toshiyuki Morii

We calculate nuclear parton distribution functions (PDFs), using the constituent quark model. We find the bounded valon distributions in a nuclear to be related to free valon distributions in a nucleon. By using improved bounded valon…

High Energy Physics - Phenomenology · Physics 2009-11-10 S. Atashbar Tehrani , Ali N. Khorramian , A. Mirjalili

The hard-gluonic contribution to the first moment of the polarized proton structure function $g_1^p(x)$ is dependent of the factorization convention chosen in defining the quark spin density and the hard cross section for photon-gluon…

High Energy Physics - Phenomenology · Physics 2009-10-28 Hai-Yang Cheng , Hung Hsiang Liu , Chung-Yi Wu

Requiring the positivity and counting rule, we propose a new parametrization of the polarized parton distribution which reproduce the data well. We found that the NLO analysis is absolutely necessary to extract the correct information on…

High Energy Physics - Phenomenology · Physics 2007-05-23 T. Morii

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…

High Energy Physics - Phenomenology · Physics 2009-10-28 M. Gluck , E. Reya , M. Stratmann , W. Vogelsang

We recall the physical features of the parton distributions in the quantum statistical approach of the nucleon. Some predictions from a next-to-leading order QCD analysis are compared to recent experimental results. We also consider their…

High Energy Physics - Phenomenology · Physics 2011-07-26 Jacques Soffer