QCD running coupling effects for the non-singlet structure function at small x

TL;DR

This paper extends the DGLAP evolution for non-singlet structure functions at small x by including all-order resummation of anomalous dimensions and running coupling effects, revealing a power-like asymptotic behavior with an exponent around 0.4.

Contribution

It provides explicit expressions for the non-singlet structure function incorporating both double- and single-logarithmic contributions with running coupling effects, advancing small-x QCD analysis.

Findings

Asymptotic small-x behavior is power-like with an exponent of about 0.4.

Resummation of anomalous dimensions to all orders improves the theoretical description.

Inclusion of running alpha_s effects significantly alters the small-x evolution.

Abstract

A generalization of the leading-order DGLAP evolution at small x is performed for the non-singlet structure function by resumming the leading-order DGLAP anomalous dimension to all orders in the QCD coupling. Explicit expressions are obtained for the non-singlet structure function of the deep inelastic scattering, taking into account both the double-logarithmic and the single-logarithmic contributions, including the running alpha_s effects. It is shown that when these contributions are included, the asymptotic small-x behaviour is power-like, with an exponent of about 0.4.