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arXiv · 0906.4197

Comparing AdS/CFT Calculations to HERA F_2 Data

Yuri V. Kovchegov·Zhun Lu·Amir H. Rezaeian
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Abstract

We show that HERA data for the inclusive structure function F_2(x,Q^2) at small Bjorken-x and Q^2 can be reasonably well described by a color-dipole model with an AdS/CFT-inspired dipole-proton cross section. The model contains only three free parameters fitted to data. In our AdS/CFT-based parameterization the saturation scale varies in the range of 1-3 GeV becoming independent of energy/Bjorken-x at very small x. This leads to the prediction of x-independence of the F_2 and F_L structure functions at very small x. We provide predictions for F_2 and F_L in the kinematic regions of future experiments. We discuss the limitations of our approach and its applicability region, and argue that our AdS/CFT-based model of non-perturbative physics could be viewed as complimentary to the perturbative description of data based on saturation/Color Glass Condensate physics.

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Yuri V. Kovchegov, Zhun Lu, Amir H. Rezaeian. 2009-10-08. Comparing AdS/CFT Calculations to HERA F_2 Data. https://doi.org/10.1103/physrevd.80.074023

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