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arXiv · hep-ph/0305171

Evolution at small x

A. Donnachie·P. V. Landshoff
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Abstract

At present there is no correct theory of evolution of F_2(x,Q^2) at small x. It is a mixture of hard and soft pomeron exchange and perturbative QCD very successfully describes the evolution of the hard-pomeron component. This allows the gluon density to be calculated. It is somewhat different from what is conventionally supposed, but it leads to a clean PQCD description of the data for the charm structure function. Perturbative QCD breaks down for the evolution of the soft-pomeron component of F_2(x,Q^2).

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A. Donnachie, P. V. Landshoff. 2003-05-15. Evolution at small x. https://arxiv.org/abs/hep-ph/0305171

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