Massive Quark Production in Electron Positron Annihilation to Order α 2 s †
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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 αs. 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 α(M2 Z), the running QED coupling constant at scale MZ , are given. The dominant terms close to threshold, i.e. in an expansion for small quark velocity β, are presented. The complete postscript file of this preprint, including figures, is available via anonymous ftp at www-ttp.physik.uni-karlsruhe.de (129.13.102.139) as /ttp97-42/ttp97-42.ps or via www at http://wwwttp.physik.uni-karlsruhe.de/cgi-bin/preprints. † Supported by BMBF under Contract 057KA92P, DFG under Contract Ku 502/8-1 and INTAS under Contract INTAS-93-744-ext.