A Measurement of $α_s(M_Z^2)$ from the Gross Llewellyn Smith Sum Rule

Abstract

The Gross Llewellyn Smith sum rule has been measured at different values of four-momentum transfer squared ($Q^{2}$) by combining the precise CCFR neutrino data with data from other deep-inelastic scattering experiments at lower values of $Q^{2}$. A comparison with the ${\cal O}(α^{3}_{s})$ predictions of perturbative QCD yields a determination of $α_{s}$ and its dependence on $Q^{2}$ in the range $1\,GeV^2 < Q^{2} < 20 \,GeV^{2}$. Low \qsq\ tests have greater sensitivity to \alfs(\mztwo) than high \qsq\ tests, since at low $Q^2$, $α_s$ is large and changing rapidly.