QCD Analysis of the Polarized Deep-Inelastic World Data

TL;DR

This paper presents a next-to-leading order QCD analysis of polarized deep-inelastic scattering data, deriving new parton distribution functions, determining the strong coupling constant, and assessing higher twist effects.

Contribution

It introduces updated polarized quark and gluon distributions, incorporates massive charm quark effects, and provides a new measurement of _s(M_z^2) with error analysis.

Findings

_s^{ m NLO}(M_Z^2)= 0.1132^{+0.0056}_{-0.0095}

Limits on higher twist contributions to g_1(x,Q^2)

Comparison with other groups' results

Abstract

The results of a recent next-to-leading order QCD analysis of the world data on polarized deep inelastic scattering are reported. New parameterizations are derived for the quark and gluon distributions, accounting for the massive Wilson coefficient for the charm quarks, and the value of $\alpha_s(M_z^2)$ is determined with correlated errors. We obtain $\alpha_s^{\rm NLO}(M_Z^2)= 0.1132 {array}{l} + 0.0056 -0.0095 {array}$. Limits on potential higher twist contributions to the structure function $g_1(x,Q^2)$ are derived. We also compare to the results obtained by other groups.