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Testing QCD with Hypothetical Tau Leptons

S. J. Brodsky·J. R. Pelaez·N. Toumbas
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Abstract

We construct new tests of perturbative QCD by considering a hypothetical tau lepton of arbitrary mass, which decays hadronically through the electromagnetic current. We can explicitly compute its hadronic width ratio directly as an integral over the e^+ e^- annihilation cross section ratio, R_{e^+e^-}. Furthermore, we can design a set of commensurate scale relations and perturbative QCD tests by varying the weight function away from the form associated with the V-A decay of the physical tau. This method allows the wide range of the R_{e^+e^-} data to be used as a probe of perturbative QCD.

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BibTeXRIS

S. J. Brodsky, J. R. Pelaez, N. Toumbas. 1998-10-20. Testing QCD with Hypothetical Tau Leptons. https://doi.org/10.1103/physrevd.60.037501

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