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arXiv · hep-ph/0511091

The Energy Dependence of the Saturation Scale

Masaaki Kuroda·Dieter Schildknecht
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Abstract

At low $x \cong Q^2/W^2 << 1$, in deep inelastic scattering, the photon fluctuates into a $q \bar q$ vector state that interacts via two gluons with the proton. The energy dependence is determined by the saturation scale, in our approach given by $Λ^2_{sat} (W^2) \sim (W^2)^{C_2}$. Imposing DGLAP evolution, we find $C_2^{theory} = 0.27$ in agreement with the model-independent analysis of the HERA data. Different values of the exponent $C_2$ are correlated with different ratios of the longitudinal to transverse structure function. This stresses the need for experiments to separate longitudinal and transverse contributions in deep inelastic scattering.

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Masaaki Kuroda, Dieter Schildknecht. 2005-11-09. The Energy Dependence of the Saturation Scale. https://arxiv.org/abs/hep-ph/0511091

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