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Contributions of gluon recombination to saturation phenomena

Wei Zhu·Jian-hong Ruan·Ji-feng Yang·Zhen-qi Shen
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Abstract

Parton distributions in the small $x$ region are numerically predicted by using a modified DGLAP equation with the GRV-like input distributions. We find that gluon recombination at twist-4 level obviously suppresses the rapid growth of parton densities with $x$ decrease. We show that before the saturation scale $Q^2_s$ is reached, saturation and partial saturation appear in the small $x$ behavior of parton distributions in nucleus and free proton, respectively. The antishadowing contributions to the saturation phenomena are also discussed.

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Wei Zhu, Jian-hong Ruan, Ji-feng Yang, Zhen-qi Shen. 2003-08-31. Contributions of gluon recombination to saturation phenomena. https://doi.org/10.1103/physrevd.68.094015

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