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Related papers: x-Dependent Polarized Parton Distributions

200 papers

Recent progress in the understanding of the nucleon is presented. The unpolarised structure functions are obtained with unprecedented precision from the combined H1 and ZEUS data and are used to extract proton parton distribution functions…

High Energy Physics - Experiment · Physics 2009-03-27 Cristinel Diaconu

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

We analize the use of algorithms based in x-space for the solution of renormalization group equations of DGLAP-type and test their consistency by studying bounds among partons distributions - in our specific case Soffer's inequality and the…

High Energy Physics - Phenomenology · Physics 2014-11-17 Alessandro Cafarella , Claudio Coriano' , Marco Guzzi

We present the first unbiased determination of spin-dependent, or polarized, Parton Distribution Functions (PDFs) of the proton. A statistically sound representation of the corresponding uncertainties is achieved by means of the NNPDF…

High Energy Physics - Phenomenology · Physics 2014-03-04 Emanuele Roberto Nocera

In this paper, we discuss the algorithms used in the LO evolution program for nondiagonal parton distributions in the DGLAP region and discuss the stability of the code. Furthermore, we demonstrate that we can reproduce the case of the LO…

High Energy Physics - Phenomenology · Physics 2007-05-23 Andreas Freund , Vadim Guzey

We present an introductory discussion of deep-inelastic lepton-proton scattering as a means to probe the substructure of the proton. A resume of QCD is given, emphasizing the running of the coupling constant and the DGLAP evolution…

High Energy Physics - Phenomenology · Physics 2010-03-25 Alan D. Martin

We discuss the determination of polarized parton distributions from charged-current deep-inelastic scattering experiments. We summarize the next-to-leading order treatment of charged-current polarized structure functions, their relation to…

High Energy Physics - Phenomenology · Physics 2009-10-08 Stefano Forte , Michelangelo L. Mangano , Giovanni Ridolfi

We show how parton distributions unintegrated over the parton transverse momentum, k_t, may be generated, at NLO accuracy, from the known integrated (DGLAP-evolved) parton densities determined from global data analyses. A few numerical…

High Energy Physics - Phenomenology · Physics 2010-03-19 A. D. Martin , M. G. Ryskin , G. Watt

We present a strategy for the systematic extraction of a vast amount of detailed information on polarized parton densities and fragmentation functions from semi-inclusive deep inelastic scattering l+N -> l+h+X, in both LO and NLO QCD. A…

High Energy Physics - Phenomenology · Physics 2016-09-06 Ekaterina Christova , Elliot Leader

We discuss techniques and results for the extraction of the nucleon's spin-dependent parton distributions and their uncertainties from data for polarized deep-inelastic lepton-nucleon and proton-proton scattering by means of a global QCD…

High Energy Physics - Phenomenology · Physics 2009-09-01 Daniel de Florian , Rodolfo Sassot , Marco Stratmann , Werner Vogelsang

We analize the renormalization group equations of supersymmetric QCD with N=1 for the evolution of parton distributions. For this purpose we develope a simple recursive algorithm in x-space to include both regular regions and supersymmetric…

High Energy Physics - Phenomenology · Physics 2014-11-17 Claudio Coriano

We show that already at the NLO level the DGLAP evolution kernel Pqq starts to depend on the choice of the evolution variable. We give an explicit example of such a variable, namely the maximum of transverse momenta of emitted partons and…

High Energy Physics - Phenomenology · Physics 2016-08-17 S. Jadach , A. Kusina , W. Placzek , M. Skrzypek

Using a recursive algorithm to solve the renormalization group equations of N=1 QCD (DGLAP), we describe the most general supersymmetric evolution of the parton distributions. The analysis involves the regular DGLAP evolution, a partial…

High Energy Physics - Phenomenology · Physics 2007-05-23 Claudio Coriano

A QCD analysis of the world data on polarized deep inelastic scattering is presented in next--to--leading order, including the heavy flavor Wilson coefficient in leading order in the fixed flavor number scheme. New parameterizations are…

High Energy Physics - Phenomenology · Physics 2014-11-21 Johannes Blümlein , Helmut Böttcher

We recall our recent description of quark parton densities of the proton at $Q^2=4 GeV^2$ in terms of Fermi-Dirac distributions parametrized with very few free parameters. We have also proposed some simple assumptions to relate unpolarized…

High Energy Physics - Phenomenology · Physics 2016-09-01 Claude Bourrely , Jacques Soffer

We summarize recent developments in understanding the concept of generalized parton distributions (GPDs), its relation to nucleon structure, and its application to high-Q2 electroproduction processes. Following a brief review of QCD…

High Energy Physics - Phenomenology · Physics 2009-08-24 C. Weiss

We present preliminary results on the determination of spin-dependent, or polarised, Parton Distribution Functions (PDFs) from all relevant inclusive polarised DIS data. The analysis is performed within the NNPDF approach, which provides a…

High Energy Physics - Phenomenology · Physics 2012-06-26 Emanuele R. Nocera , Stefano Forte , Giovanni Ridolfi , Juan Rojo

We present a complete order $\alpha_s$ analysis of the process $p p\to \gamma \gamma + X$ with polarized initial states, previously studied by us with leading order structure functions. We include in our calculation new sets of parton…

High Energy Physics - Phenomenology · Physics 2014-11-17 Claudio Coriano , L. E. Gordon

Parton distributions in the virtual photon target are investigated in perturbative QCD up to the next-to-next-to-leading order (NNLO). In the case $\Lambda^2 \ll P^2 \ll Q^2$, where $-Q^2$ ($-P^2$) is the mass squared of the probe (target)…

High Energy Physics - Phenomenology · Physics 2009-08-05 Takahiro Ueda , Ken Sasaki , Tsuneo Uematsu

Considering a fixed-flavor number scheme and based on laplace transdormation, we perform a leading-order and next-to-leading-order QCD analysis which are including world data on polarized structure functions $g_1$ and $g_2$. During our…

High Energy Physics - Phenomenology · Physics 2023-03-28 Hoda Nematollahi , Abolfazl Mirjalili , Shahin Atashbar Tehrani