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arXiv · 2109.02372

Analytical perturbation theory and Nucleon structure function in infrared region

Abstract

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 perturbative QCD (pQCD) at energy scale $Q^2\sim\Lambda ^2$ and even less we modify the calculations at these scales using anQCD approach and compare them with results from underlying pQCD and also with the available experimental data. In these progresses the massive perturbation theory (MPT) model is also used where an effective mass is attributed to gluons. We finally use the Jacobi polynomials formalism to transfer the calculations from Mellin moment space to Bjorken-$x$ space. To confirm the validity of anQCD approach the Gottfired sum rule is also investigated. The achieved numerical results at low energy scales are compatible with what is expected and corresponding to an admissible behaviour of parton densities.

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BibTeXRIS

L. Ghasemzadeh, A. Mirjalili, S. Atashbar Tehrani. 2021-09-06. Analytical perturbation theory and Nucleon structure function in infrared region. https://doi.org/10.1103/physrevd.104.074007

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