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Related papers: Determination of $\alpha_s$ and the Nucleon Spin D…

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In order to obtain polarised parton densities we have made next to leading order QCD fit using experimental data on deep inelastic structure functions on nucleons. This fit is compared with the updated fit to coresponding spin asymmetries.…

High Energy Physics - Phenomenology · Physics 2009-11-07 Jan Bartelski , Stanislaw Tatur

We reanalyse hyperon beta decay data to extract the corresponding F and D values. We show that flavour symmetry breaking effects lead naturally to a reduction of the $F/D$ ratio. For proton and neutron our analyses suggests $F/D = 0.49 \pm…

High Energy Physics - Phenomenology · Physics 2009-10-28 B. ~Ehrnsperger , A. ~Schäfer

A proton spin-polarizability characterizing backward Compton scattering has been extracted from a dispersion analysis of data between 33 and 309 MeV. This backward spin-polarizability, "delta" = 27.1 +/-2.2(stat+sys) +2.8/-2.4(model) in…

Nuclear Theory · Physics 2009-10-31 J. Tonnison , A. M. Sandorfi , S. Hoblit , A. M. Nathan

The spin polarization functions $(\Delta u, ~\Delta d, ~\Delta s)$ for proton are calculated in the chiral quark model ($\chi$QM) with SU(3) symmetry breaking as well as configuration mixing generated by one gluon exchange forces for the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Harleen Dahiya , Manmohan Gupta

The spin-structure functions $g_1$ and $g_2$, and the spin-dependent partial cross-section $\sigma_\mathrm{TT}$ have been extracted from the polarized cross-sections differences, $\Delta…

We re-examine the estimates of the higher twist contributions to the integral of $g_1$, the polarised structure function of the nucleon, based on QCD sum rules. By including corrections both to the perturbative contribution and to the low…

High Energy Physics - Phenomenology · Physics 2009-10-22 Graham G. Ross , R. G. Roberts

We have studied the deep inelastic scattering (DIS) of polarized charged leptons from polarized nucleon targets and evaluated the polarized nucleon structure functions $g_{1N,2N}(x,Q^2)$ as well as the nucleon asymmetries $A_{1N,2N}(x,Q^2)$…

High Energy Physics - Phenomenology · Physics 2025-05-01 F. Zaidi , M. Sajjad Athar , S. K. Singh

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

The small fraction of the quark polarization of the nucleon obtained in deep inelastic lepton scattering is a consequence of a wrong assumption on the flux of polarized virtual photons in the analysis of the data. The true flux of polarized…

High Energy Physics - Phenomenology · Physics 2016-04-12 Bogdan Povh , Thomas Walcher

We employ analytic QCD (anQCD) approach to analyze the unpolarized nucleon structure function (NSF) in deep inelastic scattering ( DIS ) processes at the next-to-leading order (NLO) accuracy. Considering the unreliable results of underlying…

High Energy Physics - Phenomenology · Physics 2021-10-13 L. Ghasemzadeh , A. Mirjalili , S. Atashbar Tehrani

The neutron spin structure function, $g_{1n}$, has been of considerable interest recently in connection with the Bjorken sum rule and the proton spin crisis. Work on this problem has concentrated on measurements at low-$x$. We recall the…

High Energy Physics - Experiment · Physics 2010-02-17 Anthony W. Thomas

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

We estimate the QCD coupling constant from a lattice calculation of the bottomonium spectrum. The second order perturbative expansion of the plaquette expectation value is employed to determine alpha_S at a scale set by the 2S-1S and 1P-1S…

High Energy Physics - Lattice · Physics 2009-10-31 SESAM Collaboration , A. Spitz , H. Hoeber , N. Eicker , S. Guesken , Th. Lippert , K. Schilling , T. Struckmann , P. Ueberholz , J. Viehoff

We present the results of our final analysis of the full data set of g_1^p(Q^2), the spin structure function of the proton, collected using CLAS at Jefferson Lab in 2000-2001. Polarized electrons with energies of 1.6, 2.5, 4.2 and 5.7 GeV…

We discuss the possible target mass corrections in the QCD analysis of nucleon's spin-dependent structure functions measured in the polarized deep-inelastic leptoproduction. The target mass correction for the QCD Bjorken sum rule is…

High Energy Physics - Phenomenology · Physics 2016-09-01 Hiroyuki KAWAMURA , Tsuneo UEMATSU

Recent progress in the field of spin physics of high energy particle interactions is reviewed with particular emphasis on the spin structure functions as measured in polarized deep inelastic lepton-nucleon scattering (DIS). New measurements…

High Energy Physics - Experiment · Physics 2011-07-19 Uta Stosslein

An alternate method is described to extract the quark contribution to the spin of the nucleon directly from the first moment of the deuteron structure function, $g^d_1$. It is obtained without recourse to the use of input on the nucleon…

High Energy Physics - Phenomenology · Physics 2009-10-31 George Igo

We analyse the available data on the polarized asymmetries $A_1$ for proton, neutron and deuteron targets. We use a homogeneous and updated set of unpolarized structure functions to derive $g_1$ from $A_1$, and we accurately correct for the…

High Energy Physics - Phenomenology · Physics 2009-10-22 G. Altarelli , P. Nason , G. Ridolfi

Polarized parton distribution functions are determined by using world data from the longitudinally polarized deep inelastic scattering experiments. A new parametrization of the parton distribution functions is adopted by taking into account…

High Energy Physics - Phenomenology · Physics 2014-11-17 Y. Goto , N. Hayashi , M. Hirai , H. Horikawa , S. Kumano , M. Miyama , T. Morii , N. Saito , T. -A. Shibata , E. Taniguchi , T. Yamanishi

Two new QCD sum rules for nucleons in nuclear matter are obtained from a mixed correlator of spin-1/2 and spin-3/2 interpolating fields. These new sum rules, which are insensitive to the poorly known four-quark condensates, provide…

Nuclear Theory · Physics 2009-10-28 R. J. Furnstahl , Xuemin Jin , Derek B. Leinweber