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arXiv · 1810.05573

Absorptive effects and power corrections in low $x$ DGLAP evolution

M. R. Pelicer·E. G. de Oliveira·A. D. Martin·M. G. Ryskin
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Abstract

We address a long standing problem concerning the scale behaviour of parton densities in the low $x$, low $Q^2$ domain. We emphasize the important role of absorptive corrections at low $x$ and use knowledge of diffractive deep inelastic scattering to exclude the absorptive effect from conventional deep inelastic data. In this way we obtain a significantly different low $x$ behaviour of the gluon density, which is now much better described by linear DGLAP evolution. Accounting also for a second power correction, which arises from the freezing of $α_s$ at low $Q^2$, leads to an essentially flat behaviour of the low $x$ gluon density.

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M. R. Pelicer, E. G. de Oliveira, A. D. Martin, M. G. Ryskin. 2019-01-15. Absorptive effects and power corrections in low $x$ DGLAP evolution. https://doi.org/10.1140/epjc%2Fs10052-018-6515-4

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