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Related papers: Quarks and Gluons in Nucleon Polarized Structure F…

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We have measured the spin-dependent structure function $g_1^p$ in inclusive deep-inelastic scattering of polarized muons off polarized protons, in the kinematic range $0.003 < x < 0.7$ and $1 GeV^2 < Q^2 < 60 GeV^2$. A next-to-leading order…

High Energy Physics - Experiment · Physics 2010-01-15 D. Adams

Experimental data obtained for the polarized Bjorken sum rule (BSR) $\Gamma_1^{p-n}(Q^2)$ are fitted by using predictions derived within a truncated operator product expansion (OPE) approach to QCD. Four QCD versions are considered:…

High Energy Physics - Phenomenology · Physics 2018-12-12 Cesar Ayala , Gorazd Cvetic , Anatoly V. Kotikov , Binur G. Shaikhatdenov

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

The recent measurements of lepton nucleon scattering with polarised neutron and deuteron targets are analysed together with the previous polarised proton data in a mutually consistent way. The detailed $x$-dependence of the polarisation…

High Energy Physics - Phenomenology · Physics 2009-10-22 F. E. Close , R. G. Roberts

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

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

Contents: 1. The sum rules or $\Gamma_{p,n}$.Theoretical status. 2. Calculations of matrix elements over the polarized nucleon by the QCD sum rule approach. 3. Twist-4 corrections to $\Gamma_{p,n}$ from QCD sum rules. 4. Gerasimov,…

High Energy Physics - Phenomenology · Physics 2009-09-25 B. L. Ioffe

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

We have made next to leading order QCD fit to the deep inelastic spin asymmetries on nucleons and we have determined polarised quark and gluon densities. The functional form for such distributions was inspired by the unpolarised ones given…

High Energy Physics - Phenomenology · Physics 2014-11-17 J. Bartelski , S. Tatur

An overview of the SMC data taking and the polarized deep inelastic scattering experiment is given. The new data on the deuteron extend the kinematic range and have considerably reduced statistical and systematic errors. The evaluation of…

High Energy Physics - Experiment · Physics 2007-05-23 Guenter Baum

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

Spin asymmetries of semi-inclusive cross sections for the production of positively and negatively charged hadrons have been measured in deep-inelastic scattering of polarized positrons on polarized hydrogen and 3He targets, in the kinematic…

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

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

The experimental status of the spin-dependent structure functions as obtained from the deep inelastic scattering experiments at CERN, SLAC, and DESY is reviewed. All data show a violation of the Ellis-Jaffe sum rule. The Bjorken sum rule is…

High Energy Physics - Experiment · Physics 2007-05-23 Gerhard K. Mallot

Some higher twist corrections to the Bjorken sum rule are estimated in the framework of a quark-diquark model of the nucleon. The parameters of the model have been previously fixed by fitting the measured higher twist corrections to the…

High Energy Physics - Phenomenology · Physics 2021-10-19 Mauro Anselmino , Francisco Caruso , Eugene Levin

The polarized structure functions of $^3He$ and $^3H$ nuclei are calculated in NLO approximation, considering and disregarding the light sea quark symmetry breaking. We employ the polarized structure function of the nucleons within the…

High Energy Physics - Phenomenology · Physics 2022-08-29 Fatemeh Arbabifar , Shahin Atashbar Tehrani

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 combination g_1^p(x) - g_1^n(x) is derived from SLAC data on polarized proton and deuteron targets, evaluated at Q^2 = 10 GeV^2, and compared with the results of SMC experiment. The agreement is satisfactory except for the points at the…

High Energy Physics - Phenomenology · Physics 2015-06-25 F. Buccella , O. Pisanti , P. Santorelli

We use the BLM scale-fixing prescription to derive a renormalization-scheme invariant relation between the coefficient function for the Bjorken sum rule for polarized deep inelastic scattering and the $R$-ratio for the $e^+e^-$ annihilation…

High Energy Physics - Phenomenology · Physics 2009-09-11 S. J. Brodsky , G. T. Gabadadze , A. L. Kataev , H. J. Lu

We have made next to leading order QCD fit to the deep inelastic spin asymmetries on nucleons and we determined polarised quark and gluon densities. The functional form for such distributions was inspired by the Martin, Roberts and Stirling…

High Energy Physics - Phenomenology · Physics 2007-05-23 Stanislaw Tatur , Jan Bartelski , Miroslaw Kurzela