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arXiv · 1402.0678

An approximate approach to the nonlinear DGLAP evaluation equation

G. R. Boroun·S. Zarrin
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Abstract

We determined the effects of the first nonlinear corrections to the gluon distribution using the solution of the QCD nonlinear Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (NLDGLAP) evolution equation at small x. By using a Laplace-transform technique, the behavior of the gluon distribution is obtained by solving the Gribov, Levin, Ryskin, Mueller and Qiu (GLR-MQ) evolution equation with the nonlinear shadowing term incorporated. We show that the strong rise that is corresponding to the linear QCD evolution equations at small x can be tamed by screening effects. Consequently, the nonlinear effects for the gluon distributions are calculated and compared with the results for the integrated gluon density from the Balitsky-Kovchegov (BK) equation. The resulting analytic expression allows us to predict the shadowing correction to the logarithmic derivative $F_{2}(x,Q^{2})$ with respect to $ln Q^{2}$ and to compare the results with H1 data and a QCD analysis fit.

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G. R. Boroun, S. Zarrin. 2014-02-04. An approximate approach to the nonlinear DGLAP evaluation equation. https://doi.org/10.1140/epjp/i2013-13119-8

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