High precision determination of the $Q^2$-evolution of the Bjorken Sum

Abstract

We present a significantly improved determination of the Bjorken Sum for 0.6$\le Q^2\le$4.8 GeV${}^2$ using precise new $g_1^p$ and $g_1^d$ data taken with the CLAS detector at Jefferson Lab. A higher-twist analysis of the $Q^2$-dependence of the Bjorken Sum yields the twist-4 coefficient $f_2^{p-n}=-0.064\pm 0.009{\pm }_{0.036}^{0.032}$. This leads to the color polarizabilities ${\chi }_E^{p-n}=-0.032\pm 0.024$ and ${\chi }_B^{p-n}=0.032\pm 0.013$. The strong force coupling is determined to be $α_{s}^{\overline{\mbox{ MS}}}(M_{Z}^{2})=0.1124\pm0.0061$, which has an uncertainty a factor of 1.5 smaller than earlier estimates using polarized DIS data. This improvement makes the comparison between ${\alpha }_s$ extracted from polarized DIS and other techniques a valuable test of QCD.

Published in Phys. Rev. D. V1: 8 pages, 3 figures. V2: Updated references; Included threshold matching in α_s evolution. Corrected a typo on the uncertainty for Λ_QCD. V3: Published version

References in corpus (9)

• Global analysis of proton elastic form factor data with two-photon exchange corrections
• The Deuteron Spin-dependent Structure Function g1d and its First Moment
• QCD Analysis of the Polarized World Data
• Experimental study of isovector spin sum rules
• Bjorken Sum Rule and pQCD frontier on the move
• Proton Spin Structure in the Resonance Region
• Nucleon spin structure at low momentum transfers
• A Precision Measurement of the Neutron Twist-3 Matrix Element $d_2^n$: Probing Color Forces
• Higher twists in polarized DIS and the size of the constituent quark

Cited by in corpus (21)

• Insights into the Emergence of Mass from Studies of Pion and Kaon Structure
• The Present and Future of QCD
• QCD Running Couplings and Effective Charges
• Determination of the Proton Spin Structure Functions for 0.05 < Q^2 < 5 GeV^2 using CLAS
• Dispersion relation analysis of the radiative corrections to $g_A$ in the neutron $\beta$-decay
• Measurement of the Bjorken Sum at very low $Q^2$
• The Light-Front Schrödinger Equation and Determination of the Perturbative QCD Scale from Color Confinement
• Radiative corrections to semileptonic beta decays: Progress and challenges
• Neutron spin structure with polarized deuterons and spectator proton tagging at EIC
• The Standard Model theory of neutron beta decay
• Strong Interaction Physics at the Luminosity Frontier with 22 GeV Electrons at Jefferson Lab
• Bjorken sum rule with hyperasymptotic precision
• Novel and self-consistency analysis of the QCD running coupling ${\alpha }_s(Q)$ in both the perturbative and nonperturbative domains
• Evaluation of Bjorken polarised sum rule with a renormalon-motivated approach
• The $\overline{\mathrm{MS}}$-scheme ${\alpha }_s^5$ QCD contributions to the Adler function and Bjorken polarized sum rule in the Crewther-type two-fold $\{\beta \}$-expanded representation
• A novel determination of non-perturbative contributions to Bjorken sum rule
• High precision measurements of alpha_s at the future EIC
• Deciphering Twist-3 Chiral-Even GPDs in the Light-Front Quark-Diquark Model
• Towards unifying perturbative and Holographic Light-Front QCD via holomorphic coupling
• Measurement of the nucleon spin structure functions for 0.01<$Q^2$<1 GeV${}^2$ using CLAS
• Experimental studies at low $Q^2$ of the spin structure of the nucleon at Jefferson Lab