Next-to-Leading order approximation of polarized valon and parton distributions

Abstract

Polarized parton distributions and structure functions of the nucleon are analyzed in the improved valon model. The valon representation provides a model to represent hadrons in terms of quarks, providing a unified description of bound state and scattering properties of hadrons. Polarized valon distributions are seen to play an important role in describing the spin dependence of parton distributions in the leading order (LO) and next-to-leading order (NLO) approximations. In the polarized case, a convolution integral is derived in the framework of the valon model. The Polarized valon distribution in a proton and the polarized parton distributions inside the valon are necessary to obtain the polarized parton distributions in a proton. Bernstein polynomial averages are used to extract the unknown parameters of the polarized valon distributions by fitting to the available experimental data. The predictions for the NLO calculations of the polarized parton distributions and proton structure functions are compared with the LO approximation. It is shown that the results of the calculations for the proton structure function, $x{g}_1^p$, and its first moment, ${\Gamma }_1^p$, are in good agreement with the experimental data for a range of values of $Q^2$. Finally the spin contribution of the valons to the proton is calculated.

arXiv comment22 pages, 7 figures. Published in Journal of High Energy Physics (JHEP)

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Cited by in corpus (10)

• Determination of pion and kaon fragmentation functions including spin asymmetries data in a global analysis
• The Jacobi Polynomials QCD analysis for the polarized structure function
• Polarized Deeply Inelastic Scattering (DIS) Structure Functions for Nucleons and Nuclei
• QCD analysis of polarized DIS and the SIDIS asymmetry world data and light sea-quark decomposition
• The NNLO non-singlet QCD analysis of parton distributions based on Bernstein polynomials
• Polarized Structure of Nucleon in the Valon Representation
• Impact of recent COMPASS data on polarized parton distributions and structure functions
• QCD analysis of structure functions in deep inelastic neutrino-nucleon scattering without using the orthogonal polynomials approach
• EMC effect and nuclear structure functions
• QCD analysis of valence structure functions using deep inelastic lepton-nucleon scattering