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Related papers: A covariant model for the nucleon spin structure

200 papers

We discuss the role of the U(1) axial anomaly in the spin structure functions of the nucleon, with particular emphasis on how one might determine its x dependence in present and future deep inelastic scattering experiments. We focus on the…

High Energy Physics - Phenomenology · Physics 2010-02-17 S. D. Bass , A. W. Thomas

In the present work we study the effect of the scalar spin coupling of constituent quarks on the nucleon electroweak properties by introducing a valence light-front wave function with two momentum scales. By comparing the results obtained…

High Energy Physics - Phenomenology · Physics 2022-01-26 W. R. B. de Araújo , E. F. Suisso , J. P. B. C. de Melo , T. Frederico , Kazuo Tsushima

We present a unified description of nuclear deep inelastic scattering (DIS) over the whole region $0<x<1$ of the Bjorken variable. Our approach is based on a relativistically covariant formalism which uses analytical properties of quark…

Nuclear Theory · Physics 2009-09-25 S. A. Kulagin , G. Piller , W. Weise

We derive the general structure of the hadronic tensor required to describe deep-inelastic scattering from an off-shell nucleon within a covariant formalism. Of the large number of possible off-shell structure functions we find that only…

Nuclear Theory · Physics 2009-09-25 W. Melnitchouk , A. W. Schreiber , A. W. Thomas

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

The off-mass-shell behavior of the nucleon structure function, $F_2^N$, is studied within an approach motivated by the Sullivan model. Deep inelastic scattering on the nucleon is considered in the second order in the pion-nucleon coupling…

Nuclear Theory · Physics 2009-09-25 A. Yu. Umnikov , F. C. Khanna , L. P. Kaptari

SMC performed an investigation of the spin structure of the nucleon by measuring deep inelastic scattering of polarised muons off polarised protons and deuterons. A summary of the results for spin structure functions and sum rules is given.

High Energy Physics - Experiment · Physics 2009-10-31 Eva-Maria Kabuss

In this work we study unpolarized spin $1/2$ baryonic deep inelastic scattering (DIS) in the regime of large Bjorken parameter $x$. We calculate the corresponding structure functions $F_{1,2}(x,q^2)$. Our approach is based on an AdS/QCD…

High Energy Physics - Phenomenology · Physics 2020-10-07 Eduardo Folco Capossoli , Miguel Angel Martín Contreras , Danning Li , Alfredo Vega , Henrique Boschi-Filho

We propose a new model of the nucleon in which quark-diquark configurations immersed in a pion cloud are treated in a manner consistent with Poincar\'e invariance. With suitably chosen parameters, the computations employing this model…

Nuclear Theory · Physics 2013-05-30 Ian C. Cloet , Gerald A. Miller

$^3$He spin-dependent structure functions, $g^3_1(x)$ and $g^3_2(x)$, which parametrize the hadronic tensor in polarized deep-inelastic scattering, were evaluated within the Poincar\'e covariant light-front framework. The Bakamjian-Thomas…

We investigate polarized deuteron structure functions at small values of the Bjorken variable, x < 0.1. In this region contributions from the coherent interaction of diffractively excited hadronic states with both nucleons become important.…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. Edelmann , G. Piller , W. Weise

In light of the improved precision of the experimental measurements and enormous theoretical progress, the nucleon form factors have been evaluated with an aim to understand how the static properties and dynamical behavior of nucleons…

High Energy Physics - Phenomenology · Physics 2017-11-03 Harleen Dahiya , Monika Randhawa

It is shown that the nuclear effects playing a relevant role in Deep Inelastic Scattering of polarized electrons by polarized $^3$He are mainly those arising from the effective proton and neutron polarizations generated by the $S'$ and $D$…

Nuclear Theory · Physics 2008-11-26 C. Ciofi degli Atti , S. Scopetta , E. Pace , G. Salme

We present a Next-to-Leading order perturbative QCD analysis of world data on the spin dependent structure functions $g_1^p, g_1^n$, and $g_1^d$, including the new experimental information on the $Q^2$ dependence of $g_1^n$. Careful…

High Energy Physics - Phenomenology · Physics 2008-11-26 The SLAC E154 Collaboration , K. Abe

Results are reported from the HERMES experiment at HERA on a measurement of the neutron spin structure function $g_1^n(x,Q^2)$ in deep inelastic scattering using 27.5 GeV longitudinally polarized positrons incident on a polarized $^3$He…

High Energy Physics - Experiment · Physics 2008-11-26 The HERMES Collaboration , K. Ackerstaff

We show that parton confinement in the final state generates large $1/Q^2$ corrections to Bjorken scaling, thus leaving less room for the logarithmic corrections. In particular, the $x$-scaling violations at large $x$ are entirely described…

High Energy Physics - Phenomenology · Physics 2009-10-28 S. A. Gurvitz

The production of slow nucleons in semi-inclusive deep inelastic electron scattering off the deuteron is investigated in the region $x \gsim 0.3$. It is shown that within the spectator mechanism the semi-inclusive cross section exhibits a…

Nuclear Theory · Physics 2009-10-30 Silvano Simula

A review on the theoretical aspects and the experimental results of polarized deep inelastic scattering and of other hard scattering processes is presented. The following items are discussed: longitudinally polarized structure functions,…

High Energy Physics - Phenomenology · Physics 2011-01-25 Bodo Lampe , Ewald Reya

We review the theory of polarized deep inelastic scattering in light of the most recent experimental data. We discuss the nucleon spin decomposition and the Bjorken sum rule. The latter is used for extraction of…

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

A new structure function analysis of CCFR deep inelastic nu-N and nubar-N scattering data is presented for previously unexplored kinematic regions down to Bjorken x=0.0045 and Q^2=0.3 GeV^2. Comparisons to charged lepton scattering data…

High Energy Physics - Experiment · Physics 2012-08-27 NuTeV Collaboration , B. T. Fleming