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arXiv · 1306.3369

Gluon saturation scale from the KGBJS equation

Krzysztof Kutak·Dawid Toton
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Abstract

The CCFM equation and its extended form with a quadratic term (KGBJS equation) are solved with fixed and running coupling constant. The solution of the KGBJS equation is compared to gluon densities resulting from the CCFM and BK equations. As the saturation scale $Q_s$ now becomes available as a function of the hard scale $p$ we observe that low values of $p$ impede its growth with $\frac 1 x$. Also, at values much larger than partons transversal momentum the saturation effects become independent on the hard scale what we call liberation of saturation scale. We also introduce the hard-scale-related saturation scale $P_s$ and investigate its energy dependence. We observe that the new scale as a function of $x$ decreases starting from the value of transversal momentum of gluon.

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Krzysztof Kutak, Dawid Toton. 2013-06-14. Gluon saturation scale from the KGBJS equation. https://doi.org/10.1007/jhep11(2013)082

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