Value of $\alpha_s$ and high twists from combined analysis $e-\mu$ DIS data

TL;DR

This paper conducts a next-to-leading order QCD analysis of combined deep inelastic scattering data to extract the strong coupling constant and high twist contributions, revealing scale dependencies and providing a precise value of _s(M_Z).

Contribution

It provides a detailed NLO analysis of multiple datasets focusing on the extraction of _s and high twist effects, highlighting their scale dependence and NNLO correction impacts.

Findings

Extracted _s(M_Z)=0.1159 b1 0.0031 with combined uncertainties.

High twist contributions depend on the QCD renormalization scale at small and moderate x.

NNLO corrections influence high twist extraction at small and moderate x.

Abstract

We perform a NLO QCD analysis of the combined SLAC-BCDMS-NMC-E665-H1-ZEUS data on inclusive deep inelastic cross section. Particular attention was paid to the extraction of strong coupling constant $\alpha_s$ and high twist (HT) contribution to the structure functions $F_2$ and $F_L$. It was shown that at small and moderate x there is a visible dependence of the extracted values of HT contribution to $F_2$ on the QCD renormalization scale, which indicates that in this region extracted HT can absorb NNLO QCD corrections. At larger x the dependence of HT on the renormalization scale is negligible and the influence of NNLO correction on their values should be less significant. The value of $\alpha_s(M_Z)=0.1159\pm0.0031$ (total) is obtained, where the error includes statistical, systematical and theoretical uncertainties.