Mass Corrections to the Vector Current Correlator †
نویسنده
چکیده
Three-loop QCD corrections to the vector current correlator are considered. The large momentum procedure is applied in order to evaluate mass corrections up to order (m2/q2)6. The inclusion of the first seven terms to the ratio R = σ(e+e− → hadrons)/σ(e+e− → μ+μ−) leads to reliable predictions from the high energy region down to relatively close to threshold. PACS numbers: 12.38.-t, 12.38.Bx, 13.65.+i, 13.85.Lg. 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 /ttp97-11/ttp97-11.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. Supported by the “Landesgraduiertenförderung” at the University of Karlsruhe.
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