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Related papers: Polarized Structure Functions in QCD

200 papers

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

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…

High Energy Physics - Phenomenology · Physics 2007-05-23 W. Vogelsang

We determine the quark distributions and structure functions for both unpolarized and polarized DIS of leptons on nucleons and nuclei. The scalar and vector mean fields in the nucleus modify the motion of the quarks inside the nucleons. By…

Nuclear Theory · Physics 2008-11-26 W. Bentz , I. C. Cloët , T. Ito , A. W. Thomas , K. Yazaki

The distribution of the spin of the nucleon among its constituents can be parametrized in the form of polarized parton distribution functions for quarks and gluons. Using all available data on the polarized structure function $g_1(x,Q^2)$,…

High Energy Physics - Phenomenology · Physics 2014-11-17 T. Gehrmann , W. J. Stirling

I present in this paper the neutron spin physics program in Hall A at Jefferson Laboratory using a polarized helium-3 target. The program encompasses several completed experiments, in which, valuable spin observables (spin dependent…

High Energy Physics - Experiment · Physics 2011-07-19 Z. -E. Meziani

Recent progress in the understanding of the nucleon is presented. The unpolarised structure functions are obtained with unprecedented precision from the combined H1 and ZEUS data and are used to extract proton parton distribution functions…

High Energy Physics - Experiment · Physics 2009-03-27 Cristinel Diaconu

Quark-hadron duality is studied in a systematic way for polarized and unpolarized structure functions, by taking into account all the available data in the resonance region. In both cases, a precise perturbative QCD based analysis of the…

High Energy Physics - Phenomenology · Physics 2009-11-11 A. Fantoni , N. Bianchi , S. Liuti

We discuss the determination of polarized parton distributions from charged-current deep-inelastic scattering experiments. We summarize the next-to-leading order treatment of charged-current polarized structure functions, their relation to…

High Energy Physics - Phenomenology · Physics 2009-10-08 Stefano Forte , Michelangelo L. Mangano , Giovanni Ridolfi

In this paper polarized valon distribution is derived from unpolarized valon distribution. In driving polarized valon distribution some unknown parameters exist which must be determined by fitting to experimental data. Here we have used…

High Energy Physics - Phenomenology · Physics 2007-05-23 Ali N. Khorramian , A. Mirjalili , S. Atashbar Tehrani

Using a simple picture of the constituent quark as a composite system of point-like partons, we construct the polarized parton distributions by a convolution between constituent quark momentum distributions and constituent quark structure…

High Energy Physics - Phenomenology · Physics 2011-07-19 Sergio Scopetta , Vicente Vento , Marco Traini

A global next-to-leading order QCD analysis of unpolarized and polarized deep-inelastic scattering data is performed with parton distributions constructed in a statistical physical picture of the nucleon. The chiral properties of QCD lead…

High Energy Physics - Phenomenology · Physics 2011-09-13 C. Bourrely , J. Soffer , F. Buccella

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

High Energy Physics - Phenomenology · Physics 2014-11-17 L. E. Gordon , G. P. Ramsey

We develop simple analytic representations of the polarized quark and gluon distributions in the nucleon at low $Q^2$ which incorporate general constraints obtained from the requirements of color coherence of gluon couplings at $x \sim 0$…

High Energy Physics - Phenomenology · Physics 2009-09-25 Stanley J. Brodsky , Matthias Burkardt , Ivan Schmidt

We describe a high statistics quenched QCD calculation of the moments of the polarized deep-inelastic structure functions g_1 and g_2 of the proton and neutron.

High Energy Physics - Lattice · Physics 2007-05-23 M. Goeckeler , R. Horsley , E. -M. Ilgenfritz , H. Perlt , P. Rakow , G. Schierholz , A. Schiller

We review the theory of polarized structure functions measured in deep-inelastic lepton-nucleon scattering, focusing on the most recent developments. We concentrate on the structure function $g_1$, emphasizing the phenomenological problems…

High Energy Physics - Phenomenology · Physics 2009-09-25 Stefano Forte

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

We investigate the polarized photon structure functions $g_1^\gamma$ and $g_2^\gamma$ which can be studied in the future polarized version of ep or e$^+$e$^-$ colliders. The NLO QCD calculations of $g_1^\gamma$ and the possible twist-3…

High Energy Physics - Phenomenology · Physics 2009-11-07 Hideshi Baba , Ken Sasaki , Tsuneo Uematsu

We present a systematic analysis of the processes $e^+ ~e^- \rightarrow e^+ ~e^- X$ to study the polarised and unpolarised photon structure functions. The effect of target photon mass, which manifests itself as new singly polarised…

High Energy Physics - Phenomenology · Physics 2015-06-25 Prakash Mathews , V. Ravindran

We study polarized-spin structure functions of the nucleon within the bosonized Nambu-Jona-Lasinio model where the nucleon emerges as a chiral soliton. We present the electromagnetic polarized structure functions, $g_{1}(x)$ and $g_{2}(x)$…

High Energy Physics - Phenomenology · Physics 2009-10-28 H. Weigel , L. Gamberg , H. Reinhardt

QCD suggests that gluons in the nucleon play an important role in {\it so-called} ``the proton spin problem''. In this talk, the behavior of the polarized gluon distribution in the nucleon is discussed by using the positivity condition of…

High Energy Physics - Phenomenology · Physics 2009-09-25 T. Morii , S. Tanaka , T. Yamanishi