Uncertainties on αS in global PDF analyses and implications for predicted hadronic cross sections

  title={Uncertainties on $\alpha$S in global PDF analyses and implications for predicted hadronic cross sections},
  author={A D Martin and William James Stirling and Robert Samuel Thorne and Graeme Watt},
  journal={The European Physical Journal C},
AbstractWe determine the uncertainty on the strong coupling αS due to the experimental errors on the data fitted in global analysis of hard-scattering data, within the standard framework of leading-twist fixed-order collinear factorisation in the $\overline{\mathrm{MS}}$ scheme, finding that αS(MZ2)=0.1202−0.0015+0.0012 at next-to-leading order (NLO) and αS(MZ2)=0.1171−0.0014+0.0014 at next-to-next-to-leading order (NNLO). We do not address in detail the issue of the additional theory… 
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