QCD Analysis of the Polarized 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 and determining the strong coupling constant with considerations of higher twist effects.

Contribution

It provides updated parameterizations of quark and gluon distributions and a new measurement of s at NLO, including potential higher twist contributions.

Findings

s(M_Z^2) = 0.1132 with uncertainties

New polarized parton distribution functions derived

Analysis of higher twist contributions to structure function g_1(x,Q^2)

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 and the value of $\alpha_s(M_z^2)$ is determined. We obtain $\alpha_s^{\rm NLO}(M_Z^2)= 0.1132~~\begin{array}{l} + 0.0056 \\ -0.0095 \end{array}$. Potential higher twist contributions to the structure function $g_1(x,Q^2)$ are considered.