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Related papers: Polarized Parton Densities in the Nucleon

200 papers

We perform a global leading-order QCD fit to recent polarized structure function data in order to extract a consistent set of spin-dependent parton distributions. Assuming that there is no significant intrinsic polarization of the quark…

High Energy Physics - Phenomenology · Physics 2007-05-23 T. Gehrmann , W. J. Stirling

We studied the impact of future Electron Ion Collider inclusive and semi-inclusive polarized deep inelastic scattering data will have on the determination of the helicity parton distributions. Supplementing the Monte Carlo sampling variant…

High Energy Physics - Phenomenology · Physics 2020-07-17 Elke C. Aschenauer , Ignacio Borsa , Gonzalo Lucero , Ana S. Nunes , Rodolfo Sassot

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

A statistical model for the parton distributions in the nucleon has proven its efficiency in the analysis of deep inelastic scattering data, so we propose to extend this approach to the description of unpolarized fragmentation functions for…

High Energy Physics - Phenomenology · Physics 2009-11-10 Claude Bourrely , Jacques Soffer

We present a new set of parton distributions obtained at NNLO. These differ from the previous sets available at NNLO due to improvements in the theoretical treatment. In particular we include a full treatment of heavy flavours in the region…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. D. Martin , W. J. Stirling , R. S. Thorne , G. Watt

The quantum statistical parton distributions approach proposed more than one decade ago is revisited by considering a larger set of recent and accurate Deep Inelastic Scattering experimental results. It enables us to improve the description…

High Energy Physics - Phenomenology · Physics 2015-12-09 Claude Bourrely , Jacques Soffer

The quantum statistical parton distributions approach proposed more than one decade ago is revisited by considering a larger set of recent and accurate Deep Inelastic Scattering experimental results. It enables us to improve the description…

High Energy Physics - Phenomenology · Physics 2015-10-22 Jacques Soffer , Claude Bourrely

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

The QCD analysis of deep inelastic diffractive scattering is performed assuming the dominance of the "soft" pomeron exchange and simple, physically motivated parametrization of parton distributions in a pomeron. Results of the analysis are…

High Energy Physics - Phenomenology · Physics 2008-11-26 K. Golec-Biernat , J. Kwiecinski

We present the basic aspects of deep inelastic phenomena in the framework of the QCD parton model. After recalling briefly the standard kinematics, we discuss the physical interpretation of unpolarized and polarized structure functions in…

High Energy Physics - Phenomenology · Physics 2007-05-23 C. Bourrely , J. Soffer

We perform the first global QCD analysis of polarized inclusive and semi-inclusive deep-inelastic scattering and single-inclusive $e^+e^-$ annihilation data, fitting simultaneously the parton distribution and fragmentation functions using…

High Energy Physics - Phenomenology · Physics 2017-10-04 J. J. Ethier , N. Sato , W. Melnitchouk

The H1 and ZEUS Collaborations have performed new next-to-leading order QCD analyses to determine the parton density functions of the proton. QCD fits are performed using inclusive neutral and charged deep inelastic scattering cross…

High Energy Physics - Experiment · Physics 2017-08-23 C. Gwenlan

A recent global QCD analysis of jet production and other polarized scattering data has found the presence of negative solutions for the gluon helicity distribution in the proton, $\Delta g$, along with the traditional $\Delta g > 0$…

High Energy Physics - Phenomenology · Physics 2026-05-04 R. M. Whitehill , Yiyu Zhou , N. Sato , W. Melnitchouk

We review the present status of polarized structure functions measured in deep-inelastic scattering. We discuss the x and Q^2 dependence of the structure function g_1, and how it can be used to test perturbative QCD at next-to-leading order…

High Energy Physics - Phenomenology · Physics 2008-02-03 Stefano Forte

Nuclear parton distributions $f_A(x,Q^2)$ are studied within a framework of the DGLAP evolution. Measurements of $F_2^A/F_2^D$ in deep inelastic $lA$ collisions, and Drell--Yan dilepton cross sections measured in $pA$ collisions are used as…

High Energy Physics - Phenomenology · Physics 2015-06-25 K. J. Eskola , V. J. Kolhinen , P. V. Ruuskanen , C. A. Salgado

A review of recent experimental and theoretical studies of characteristics of neutrino deep-inelastic scattering is presented. Special attentition is paid to the determination of $\alpha_s$ and $1/Q^2$ non-perturbative effects from QCD fits…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. L. Kataev

We present a comprehensive new global QCD analysis of unpolarized parton distribution functions (PDFs) based upon proton, deuteron and $A\!=\!3$ data, including the latest inclusive deep-inelastic scattering (DIS) measurements from…

High Energy Physics - Phenomenology · Physics 2026-05-04 C. Cocuzza , W. Melnitchouk , N. Sato , A. W. Thomas

We analyze the order-$\alpha_s^2$ QCD corrections to semi-inclusive deep inelastic scattering and present results for processes initiated by a gluon. We focus in the most singular pieces of these corrections in order to obtain the hitherto…

High Energy Physics - Phenomenology · Physics 2016-08-16 A. Daleo , C. A. García Canal , R. Sassot

The present status of the longitudinal polarized parton densities (PDFs) and the contribution of their first moments to the nucleon spin is discussed. Special attention is paid to the role of higher twist effects in determining the PDFs and…

High Energy Physics - Phenomenology · Physics 2009-08-24 Elliot Leader , Alexander V. Sidorov , Dimiter B. Stamenov

The coplete analysis of the model-independent leading radiative corrections to cross-section and polarization observables in semi-inclusive deep-inelastic electron-nucleus scattering with detection of a proton and scattered electron in…

High Energy Physics - Phenomenology · Physics 2014-11-17 A. V. Afanas'ev , I. Akushevich , G. I. Gakh , N. P. Merenkov