Comparing AdS/CFT Calculations to HERA F_2 Data
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.
Cite
@article{arxiv.0906.4197,
title = {Comparing AdS/CFT Calculations to HERA F_2 Data},
author = {Yuri V. Kovchegov and Zhun Lu and Amir H. Rezaeian},
journal= {arXiv preprint arXiv:0906.4197},
year = {2010}
}
Comments
23 pages, 10 figures; v3: new plots added showing our model predictions for charm and longitudinal structure functions and photoproduction cross-section, discussion extended. The version to appear in PRD