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 — preprints:1997:ttp97-42 [2016/03/17 11:03] (current) Line 1: Line 1: + ====== TTP97-42 Massive Quark Production in Electron Positron Annihilation to Order  $\alpha_s^2$ ====== + + + Recent analytical and numerical results for the three-loop + polarization function allow to present a phenomenological analysis + of the cross section for massive quark production in electron positron + annihilation to order $\alpha_s^2$. Numerical predictions based on fixed + order perturbation theory are presented for charm and bottom + production above 5 and 11.5 GeV, respectively. The contribution + from these energy regions to $\alpha(M_Z^2)$, the running QED coupling + constant at scale M_Z, are given. The dominant terms close to threshold, + i.e. in an expansion for small quark velocity $\beta$, are presented. + + + |**K.G. Chetyrkin, A.H. Hoang, J.H. K\"uhn, M. Steinhauser and T. Teubner**  | + |** Eur.Phys.J. C 2 137-150 1998  **  | + | {{preprints:1997:ttp97-42.pdf|PDF}} {{preprints:1997:ttp97-42.ps|PostScript}} [[http://arxiv.org/abs/hep-ph/9711327|arXiv]]   | + | |