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Related papers: A covariant model for the nucleon spin structure

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The possibility of a reliable extraction of the neutron deep inelastic structure function, $F_2^n(x)$, for $ x < 0.85$ from joint measurements of deep inelastic structure functions of deuteron, $^{3}He$ and $^{3}H$ is investigated. The…

Nuclear Theory · Physics 2009-11-07 E. Pace , G. Salme` , S. Scopetta , A. Kievsky

We present the first measurement of the Q^2-dependence of the neutron spin structure function g_2^n at five kinematic points covering 0.57 (GeV/c)^2 <= Q^2 <= 1.34 (GeV/c)^2 at x~0.2. Though the naive quark-parton model predicts g_2=0,…

Nuclear Experiment · Physics 2008-11-26 K. Kramer

We show that all four of the nucleon form factors can be very well explained using the manifestly covariant spectator theory. The nucleon is modeled as a spherical state of three constituent quarks with electromagnetic form factors, all…

Nuclear Theory · Physics 2014-11-18 Franz Gross , Peter Agbakpe

The inclusive double-spin asymmetry, A_1^p, has been measured at COMPASS in deepinelastic polarised muon scattering off a large polarised NH3 target. The data, collected in the year 2007, cover the range Q2 > 1 (GeV/c)^2, 0.004 < x < 0.7…

High Energy Physics - Experiment · Physics 2014-11-20 The COMPASS Collaboration , M. G. Alekseev

We have measured the spin-dependent structure function $g_1^p$ of the proton in deep inelastic scattering of polarized muons off polarized protons, in the kinematic range $0.003<x<0.7$ and $1\,\mbox{GeV}^2<Q^2<60\,\mbox{GeV}^2$. Its first…

High Energy Physics - Phenomenology · Physics 2010-01-15 the SMC

We analyze the quark mass dependence of photon gluon fusion in polarized deep inelastic scattering for both the intrinsic and extrinsic gluon distributions of the nucleon. We calculate the effective number of flavors for each of the heavy…

High Energy Physics - Phenomenology · Physics 2009-09-11 Steven Bass , Stanley J. Brodsky , Ivan Schmidt

A next-to-leading order QCD calculation of non-singlet spin structure function, $g_{1}^{NS} $ is presented within the valon representation of Hadrons. In the valon model, it is assumed that a nucleon is composed of three dressed valence…

High Energy Physics - Phenomenology · Physics 2014-11-21 Fatemeh Taghavi Shahri , Firooz Arash

We study the chiral-odd transversity spin-dependent quark distribution function $h_1 (x)$ of the nucleon in a constituent quark model. The twist-2 structure functions, $f_1(x)$, $g_1(x)$ and $h_1(x)$ are calculated within the diquark…

High Energy Physics - Phenomenology · Physics 2009-10-30 K. Suzuki , T. Shigetani

The production of slow nucleons in semi-inclusive deep inelastic electron scattering off the deuteron is investigated in the region $x \gsim 0.3$ for kinematical conditions accessible at $HERA$. Within the spectator mechanism the…

Nuclear Theory · Physics 2007-05-23 Silvano Simula

I introduce a gauge invariant decomposition of the nucleon spin into quark helicity, quark orbital, and gluon contributions. The total quark (and hence the quark orbital) contribution is shown to be measurable through virtual Compton…

High Energy Physics - Phenomenology · Physics 2009-10-28 Xiangdong Ji

The neutron's deep-inelastic structure functions provide essential information for the flavor separation of the nucleon parton densities, the nucleon spin decomposition, and precision studies of QCD phenomena in the flavor-singlet and…

High Energy Physics - Phenomenology · Physics 2014-11-03 W. Cosyn , V. Guzey , D. W. Higinbotham , C. Hyde , S. Kuhn , P. Nadel-Turonski , K. Park , M. Sargsian , M. Strikman , C. Weiss

In the framework of Anisotropic Chromo Dynamics, a non-perturbative model of QCD based on magnetic condensation in the vacuum, we develope a picture of the Pomeron. Within this model we are able to calculate the diffractive contribution to…

High Energy Physics - Phenomenology · Physics 2009-10-28 L. Dick , V. Karapetian , R. Barni , G. Preparata

We develop the theoretical framework for semi-inclusive deep-inelastic scattering on a polarized spin-1 target and apply it to scattering on the polarized deuteron with spectator nucleon tagging. In Part I (this article) we present the…

High Energy Physics - Phenomenology · Physics 2026-03-26 W. Cosyn , C. Weiss

The isospin asymmetry of the sea quark distribution as well as the unexpectedly small quark spin fraction of the nucleon are two outstanding discoveries recently made in the physics of deep-inelastic structure functions. We evaluate here…

High Energy Physics - Phenomenology · Physics 2009-10-30 Masashi Wakamatsu , Takanori Kubota

Nucleon structure functions are studied within the chiral soliton approach to the bosonized Nambu-Jona-Lasinio model. The valence quark approximation is employed which is justified for moderate constituent quark masses ($\sim$ 400 MeV) as…

High Energy Physics - Phenomenology · Physics 2016-09-01 H. Weigel , L. Gamberg , H. Reinhardt

A covariant formulation of spin-dependent deep-inelastic scattering from nuclei is presented. In the relativistic impulse approximation the inclusive nuclear cross section is described in terms of the amplitude for forward, virtual-photon…

Nuclear Theory · Physics 2008-11-26 G. Piller , W. Melnitchouk , A. W. Thomas

Results for the proton and neutron electric and magnetic form factors as well asthe nucleon axial and induced pseudoscalar form factors are presented for the chiral constituent quark model based on Goldstone-boson-exchange dynamics. The…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Boffi , L. Ya. Glozman , W. Klink , W. Plessas , M. Radici , R. F. Wagenbrunn

A rest frame valence quark model is applied to the deep inelastic scattering of charged leptons by protons. The parameters of the model are determined by a fit to unpolarized electron cross sections. The model then can be used to calculate…

High Energy Physics - Phenomenology · Physics 2007-05-23 Jerrold Franklin

Beginning with precise data on the ratio of structure functions in deep inelastic scattering (DIS) from $^3$He and $^3$H, collected on the domain $0.19 \leq x_B \leq 0.83$, where $x_B$ is the Bjorken scaling variable, we employ a robust…

High Energy Physics - Phenomenology · Physics 2022-05-27 Zhu-Fang Cui , Fei Gao , Daniele Binosi , Lei Chang , Craig D. Roberts , Sebastian M. Schmidt

We present a detailed analysis of the polarized and the unpolarized deep inelastic scattering structure functions of the proton, g_1^p and F_2^p respectively, in the context of a holographic dual description based on type IIB superstring…

High Energy Physics - Phenomenology · Physics 2023-09-11 Ignacio Borsa , David Jorrin , Rodolfo Sassot , Martin Schvellinger