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Related papers: Polarized Parton Distributions in the Nucleon

200 papers

Optimum nuclear parton distributions are determined by an analysis of muon and electron deep inelastic scattering data. Assuming simple A dependence and polynomial functions of x and 1-x for nuclear modification of parton distributions, we…

High Energy Physics - Phenomenology · Physics 2015-06-25 M. Hirai , S. Kumano , M. Miyama

I begin with a general discussion about importance of constructing a picture of the nucleon in terms of QCD degrees of freedom, emphasizing the role of spin structure functions. I then give a short overview on the theoretical and…

High Energy Physics - Phenomenology · Physics 2007-05-23 Xiangdong Ji

We present a systematic study of the proton spin structure in terms of measurable parton distributions. For a transversely-polarizedproton, we derive a polarization sum rule from the leading generalized parton distributions appearing in…

High Energy Physics - Phenomenology · Physics 2012-10-18 Xiangdong Ji , Xiaonu Xiong , Feng Yuan

In order to determine polarized parton densities in nucleon we have made fits using all experimental data on spin asymmetries measured in the deep inelastic scattering on different nucleon targets. We have used in our analysis next to…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. Bartelski , S. Tatur

We review the perturbative evolution of the polarized structure functions g_1 and their associated parton distribution functions, with particular emphasis on the anomalous coupling of the first moment of the polarized gluon distribution. We…

High Energy Physics - Phenomenology · Physics 2008-02-03 R. D. Ball

We present a consistent calculation of the structure functions within a light-front constituent quark model of the nucleon. Relativistic effects and the relevance of the covariance constraints are analyzed for polarized parton…

High Energy Physics - Phenomenology · Physics 2007-05-23 P. Faccioli , F. Cano , M. Traini , V. Vento

Generalized parton distributions are a new type of hadronic observables which has recently stimulated great interest among theorists and experimentalists alike. Introduced to delineate the spin structure of the nucleon, the orbital angular…

High Energy Physics - Lattice · Physics 2009-11-07 Xiangdong Ji

We present a fit to spin asymmetries which gives polarized quark distributions. These functions are closely related to the ones given by the newest Martin, Roberts and Stirling fit for unpolarized structure functions. The integrals of…

High Energy Physics - Phenomenology · Physics 2009-10-28 Jan Bartelski , Stanisław Tatur

We study parametrization of polarized parton distribution functions in the \alpha_s leading order (LO) and in the next-to-leading order (NLO). From \chi^2 fitting to the experimental data on A_1, optimum polarized distribution functions are…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Hirai , H. Kobayashi , M. Miyama

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

By assuming that there is no significant intrinsic polarization of the gluon, we have computed the polarized quark contributions to the proton's spin under SU(3) flavor symmetry breaking for the polarized sea and have performed a global…

High Energy Physics - Phenomenology · Physics 2009-10-28 Chung-Yi Wu

We investigate the possibility to draw conclusions on the sign of the spin-dependent gluon distribution, $\Delta G(x, Q^2)$, from existing polarized DIS data. The spin-dependent parton distributions $\Delta u_v, \Delta d_v, \Delta {\bar u},…

High Energy Physics - Phenomenology · Physics 2007-05-23 W. -D. Nowak , A. V. Sidorov , M. V. Tokarev

We report the polarized parton distributions proposed by the Asymmetry Analysis Collaboration (AAC). Using parametrized distributions at Q^2=1 GeV^2 and measured A_1 data, we determine optimum polarized distributions in the leading order…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Kumano

Generalized parton distributions have been introduced in recent years as a suitable theoretical tool to study the structure of the nucleon. Unifying the concepts of parton distributions and hadronic form factors, they provide a…

High Energy Physics - Phenomenology · Physics 2011-09-30 Sigfrido Boffi , Barbara Pasquini

An updated next-to-leading order (NLO) QCD analysis of the spin asymmetries A_1^N(x,Q^2) and parton distributions delta f(x,Q^2) in longitudinally polarized deep-inelastic lepton-nucleon scattering is presented within the framework of the…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Stratmann

Nuclear parton distribution functions are obtained by a chi^2 analysis of lepton deep inelastic experimental data. It is possible to determine valence-quark distributions at medium x and antiquark distributions at small x; however, the…

High Energy Physics - Phenomenology · Physics 2017-08-23 S. Kumano

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

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

Polarized parton distributions and structure functions of the nucleon are analyzed in the improved valon model. The valon representation provides a model to represent hadrons in terms of quarks, providing a unified description of bound…

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

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