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arXiv · 0901.1294

Can we trust small x resummation?

Stefano Forte·Guido Altarelli·Richard D. Ball
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Abstract

We review the current status of small x resummation of evolution of parton distributions and of deep-inelastic coefficient functions. We show that the resummed perturbative expansion is stable, robust upon different treatments of subleading terms, and that it matches smoothly to the unresummed perturbative expansions, with corrections which are of the same order as the typical NNLO ones in the HERA kinematic region. We discuss different approaches to small x resummation: we show that the ambiguities in the resummation procedure are small, provided all parametrically enhanced terms are included in the resummation and properly matched.

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Stefano Forte, Guido Altarelli, Richard D. Ball. 2009-01-09. Can we trust small x resummation?. https://doi.org/10.1016/j.nuclphysbps.2009.03.114

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