Bjorken sum rule in QCD with analytic coupling

TL;DR

This paper investigates the Bjorken sum rule in QCD using three analytic coupling approaches, demonstrating good agreement with experimental data in the low to moderate energy range, and highlighting the effectiveness of these frameworks.

Contribution

It introduces and compares three analytic QCD frameworks (APT, Two-delta, Three-delta) for the Bjorken sum rule, showing their compatibility with experimental results.

Findings

All three approaches agree well with experimental data for 0.5 GeV2 < Q2 < 3 GeV2.

The frameworks require only one higher-twist term to fit the data.

Results are consistent across three- and four-loop MiniMOM schemes.

Abstract

We present details of study of the Bjorken polarized sum rule carried out recently in [1] within the range of energies where the data were collected by JLAB collaboration, 0.05 GeV2 < Q2 < 3 GeV2. Three approaches to QCD with analytic (holomorphic) coupling are considered: Analytic Perturbation Theory (APT), Two-delta analytic QCD, and Three-delta lattice-motivated analytic QCD in the three-loop and four-loop MiniMOM schemes. The new frameworks with respective couplings give results which agree well with the experimental data for 0.5 GeV2 < Q2 < 3GeV2 already when only one higher-twist term is taken into account.