Heavy Quark Vacuum Polarisation to Three Loops
نویسندگان
چکیده
The real and imaginary part of the vacuum polarisation function Π(q2) induced by a massive quark is calculated in perturbative QCD up to order αs. The method is described and the results are presented. This extends the calculation by Källén and Sabry from two to three loops. The complete postscript file of this preprint, including figures, is available via anonymous ftp at ttpux2.physik.uni-karlsruhe.de (129.13.102.139) as /ttp95-41/ttp95-41.ps or via www at http://wwwttp.physik.uni-karlsruhe.de/cgi-bin/preprints/ Report-no: TTP95-41. † Work supported by BMFT under Contract 056KA93P6, DFG under Contract Ku502/6-1 and INTAS under Contract INTAS-93-0744.
منابع مشابه
Heavy-quark QCD vacuum polarisation function: analytical results at four loops
Fully analytical results for the first two moments of the heavy-quark vacuum polarisation function at four loops in quantum chromo-dynamics are presented. PACS: 12.38.-t, 12.38.Bx, 13.66.Bc, 13.85.Lg ∗Permanent address: Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, 141980, Dubna (Moscow region), Russia.
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تاریخ انتشار 1995