Quantum-chromodynamic analysis ofeNdeep-inelastic scattering data

Abstract

In the context of quantum chromodynamics (QCD), an analysis is presented of a compilation of $\mathrm{eN}$ deepinelastic scattering data taken at SLAC. Included are data for ${F}_{2}^{\mathrm{ep}}$, ${F}_{2}^{\mathrm{ed}}$, ${F}_{2}^{\mathrm{ep}}\ensuremath{-}{F}_{2}^{\mathrm{en}}$, and $R$. The interaction between the logarithmic scaling violation from ${\ensuremath{\alpha}}_{s}$ and the power-law scaling violation from higher-twist terms is discussed. This interaction can affect the determination of the parameter $\ensuremath{\Lambda}$ and can alter the predictions for the ratios of anomalous dimensions. Furthermore, we show that, in the context of QCD, higher-twist terms may be able to account for the observed value of $R=\frac{{\ensuremath{\sigma}}_{L}}{{\ensuremath{\sigma}}_{T}}$ which appears to be anomalously large. Different experiments have made different assumptions for the value of $R$ used in extracting ${F}_{2}$ from their data. We show that these differences can account for the discrepancies in the relative normalizations of ${F}_{2}$ from these experiments and also can have a significant effect on the value of $\ensuremath{\Lambda}$ obtained.