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Related papers: A covariant model for the nucleon spin structure

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Using the covariant spectator theory (CST), we present the results of a valence quark-diquark model calculation of the nucleon structure function f(x) measured in unpolarized deep inelastic scattering (DIS), and the structure functions…

High Energy Physics - Phenomenology · Physics 2012-05-24 Franz Gross , G. Ramalho , M. T. Pena

So far the analyses of the polarized structure functions of the proton and neutron have been limited to the evaluation of their integrals and comparing them to the prediction of the static quark model of the nucleon. We extended our…

High Energy Physics - Phenomenology · Physics 2018-10-30 B. Povh , M. Rosina

Nucleon structure functions, as measured in deep-inelastic lepton scattering, are studied within a covariant scalar diquark spectator model. Regarding the nucleon as an approximate two-body bound state of a quark and diquark, the…

High Energy Physics - Phenomenology · Physics 2015-06-25 K. Kusaka , G. Piller , A. W. Thomas , A. G. Williams

We present a model description of the nucleon valence structure function applicable over the entire region of the Bjorken variable x, and above moderate values of Q**2 (> 1 GeV**2). We stress the importance of describing the complete…

Nuclear Theory · Physics 2014-11-18 S. A. Kulagin , W. Melnitchouk , T. Weigl , W. Weise

We study deep-inelastic scattering from polarized nuclei within a covariant framework. A clear connection is established between relativistic and non-relativistic limits, which enables a rigorous derivation of convolution formulae for the…

High Energy Physics - Phenomenology · Physics 2009-09-25 S. A. Kulagin , W. Melnitchouk , G. Piller , W. Weise

We start from an MIT-bag model calculation which provides information about the constituent quark distributions in the nucleon. The constituent quarks, however, are themselves considered as complex objects whose partonic substructure is…

High Energy Physics - Phenomenology · Physics 2009-09-25 J. Keppler , H. M. Hofmann

Using the manifestly covariant spectator theory, and modeling the nucleon as a system of three constituent quarks with their own electromagnetic structure, we show that all four nucleon electromagnetic form factors can be very well…

Nuclear Theory · Physics 2008-11-26 Franz Gross , G. Ramalho , M. T. Pena

We review the theory and phenomenology of deep inelastic polarized lepton-nucleon scattering in the light of recent data with a deuteron target from the SMC at CERN and a Helium 3 target from the E142 experiment at SLAC. After including…

High Energy Physics - Phenomenology · Physics 2008-02-03 John Ellis , Marek Karliner

Deep-inelastic structure functions are studied within a covariant scalar diquark spectator model of the nucleon. Treating the target as a two-body bound state of a quark and a scalar diquark, the Bethe-Salpeter equation (BSE) for the bound…

High Energy Physics - Phenomenology · Physics 2010-02-17 K. Kusaka , G. Piller , A. W. Thomas , A. G. Williams

The covariant spectator formalism is used to model the nucleon and the $\Delta$(1232) as a system of three constituent quarks with their own electromagnetic structure. The definition of the ``fixed-axis'' polarization states for the diquark…

High Energy Physics - Phenomenology · Physics 2008-11-26 G. Ramalho , M. T. Pena , Franz Gross

Expressions for the nucleon wave functions in the covariant spectator theory (CST) are derived. The nucleon is described as a system with a off-mass-shell constituent quark, free to interact with an external probe, and two spectator…

High Energy Physics - Phenomenology · Physics 2012-05-24 Franz Gross , G. Ramalho , M. T. Pena

The nucleon spin structure is studied at COMPASS via the measurement of the spin dependent properties of deep inelastic muon-deuteron scattering. Both inclusive and semi-inclusive observables are investigated, with the emphasis put on the…

High Energy Physics - Experiment · Physics 2015-06-25 Yann Bedfer

Deep inelastic structure functions for the nucleon are obtained in a constituent quark model on the light cone. In the Bjorken limit the parton model is derived. Structure functions from the hadronic tensor at the scale $\mu \sim 0.25$ GeV…

Nuclear Theory · Physics 2009-09-25 H. J. Weber

The proton structure function is re-deduced from the data of deep inelastic electron-proton scattering after enhanced correction that is made due to the multiple scattering effect. The Glauber approach is used to account for the multiple…

High Energy Physics - Phenomenology · Physics 2007-05-23 N. M. Hassan , W. R. El-Harby , R. W. El-Moualed And M. T. Hussein

The alternative to the standard formulation of the quark-parton model is proposed. Our relativistically covariant approach is based on the solution of the master equations relating the structure and distribution functions, which…

High Energy Physics - Phenomenology · Physics 2007-05-23 P. Zavada

The experiment E155 at SLAC measured the spin structure functions g_1 and g_2 of the proton and deuteron. The experiment used deep inelastic scattering of 48.3 GeV longitudinally polarized electrons incident on polarized solid ^{15}NH_3 and…

High Energy Physics - Experiment · Physics 2007-05-23 Gregory S. Mitchell

We re-analyze data on deep inelastic polarized lepton-nucleon scattering, with particular attention to testing the Bjorken sum rule and estimating the quark contributions to the nucleon spin. Since only structure function data at fixed…

High Energy Physics - Phenomenology · Physics 2009-09-25 John Ellis , Marek Karliner

Deep inelastic polarized and unpolarized structure functions for a free nucleon are obtained in a modified Center-of-Mass bag model, which includes the symmetry breaking effects from spin-dependent interactions. The quark distribution…

High Energy Physics - Phenomenology · Physics 2014-11-17 X. Song , J. S. McCarthy

New experimental results on the spin dependent structure functions g_1 and g_2 which are determined from deep-inelastic scattering experiments at CERN, SLAC and DESY are reported. These results are used to evaluate the Bjorken sum rule and…

High Energy Physics - Phenomenology · Physics 2008-02-03 J. Nassalski

The phenomenon of scaling in deep inelastic lepton-nucleon scattering is usually explained in terms of the Feynman parton model, and the logarithmic corrections to scaling are explained in the framework of perturbative QCD. For testing the…

High Energy Physics - Phenomenology · Physics 2016-09-01 Felix. M. Lev
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