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تسجيل مستخدم جديدAn analysis of polarized parton distribution functions with nonlinear QCD evolution equations
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We present the polarized parton distribution functions from the QCD analysis of the worldwide deep inelastic scattering data with polarized beams, based on the dynamical parton distribution model. All the sea quarks and gluons are dynamically generated from QCD radiations, with the nonperturbative input contains only the polarized valence quark distributions. This approach leads to a simple parametrization, which has only four free parameters. In the analysis, we apply the DGLAP equations with parton-parton recombination corrections. The parameterized nonperturbative input at an extremely low $Q_0^2$ reproduces well the spin-dependent structure functions measured at high $Q^{2}$. Comparisons with some other polarized parton distribution functions are also shown. Our analysis gives the positive polarized gluon distribution and it suggests that the gluon distribution plays an important role to the proton spin content. The polarized antiquark distributions are non-zero at high $Q^2$, based on this dynamical parton model analysis.
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