Tau hadronic spectral function moments: perturbative expansion and αs extractions
نویسندگان
چکیده
منابع مشابه
Measurement of the Strong Coupling Constant αs and the Vector and Axial-Vector Spectral Functions in Hadronic Tau Decays
The spectral functions of the vector current and the axial-vector current have been measured in hadronic τ decays using the OPAL detector at LEP. Within the framework of the Operator Product Expansion a simultaneous determination of the strong coupling constant αs, the non-perturbative operators of dimension 6 and 8 and of the gluon condensate has been performed. Different perturbative descript...
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The perturbative quark–mass corrections to the τ hadronic width are analysed to O(αsm 2 q), using the presently available theoretical information. The behaviour of the perturbative series is investigated in order to assess the associated uncertainties. The implications for the determination of the strange quark mass from τ decay data are discussed.
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ژورنال
عنوان ژورنال: Nuclear and Particle Physics Proceedings
سال: 2016
ISSN: 2405-6014
DOI: 10.1016/j.nuclphysbps.2015.09.340