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arXiv · hep-ph/0303031

Next-to-Leading Order Constituent Quark Structure and Hadronic Structure Functions

Abstract

We calculate the partonic structure of a constituent quark in the Next-to-Leading Order framework. The structure of any hadron can be obtained thereafter using a convolution method. Such a procedure is used to generate the structure function of proton and pion in NLO, neglecting certain corrections to $Λ_{QCD}$. It is shown that while the constituent quark structure is generated purely perturbatively and accounts for the most part of the hadronic structure, there is a few percent contributions coming from the nonperturbative sector in the hadronic structure. This contribution plays the key role in explaining the SU(2) symmetry breaking of the nucleon sea and the observed violation of Gottfried sum rule. These effects are calculated. We obtained an Excellent agreement with the experimental data in a wide range of $x=[10^{-6}, 1]$ and $Q^{2}=[0.5, 5000]$ $GeV^{2}$ for the proton structure function. We have also calculated Pion structure and compared it with the existing data. Again, the model calculations agree rather well with the data from experiment.

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BibTeXRIS

F. Arash, A. N. Khorramian. 2003-03-05. Next-to-Leading Order Constituent Quark Structure and Hadronic Structure Functions. https://doi.org/10.1103/physrevc.67.045201

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