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arXiv · hep-ph/9806212

The description of $F_2$ at low $Q^2$

A. D. Martin·M. G. Ryskin·A. M. Stasto
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Abstract

We analyse the data for the proton structure function $F_2$ over the entire $Q^2$ domain, including especially low $Q^2$, in terms of perturbative and non-perturbative QCD contributions. The small distance configurations are given by perturbative QCD, while the large distance contributions are given by the vector dominance model and, for the higher mass $q \bar{q}$ states, by the additive quark approach. The interference between states of different $q\bar{q}$ mass (in the perturbative contribution) is found to play a crucial role in obtaining an excellent description of the data throughout the whole $Q^2$ region, including photoproduction.

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A. D. Martin, M. G. Ryskin, A. M. Stasto. 1998-06-21. The description of $F_2$ at low $Q^2$. https://doi.org/10.1007/s100529801035

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