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arXiv · hep-ph/9909225

Asymptotic structure of perturbative series for tau lepton observables

J. G. Koerner·F. Krajewski·A. A. Pivovarov
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Abstract

We analyze tau lepton decay observables, namely moments of the hadronic spectral density in the finite energy interval (0,M_τ), within finite order perturbation theory including α_s^4 corrections. The start of asymptotic growth of perturbation theory series is found at this order in a scheme invariant manner. We establish the ultimate accuracy of finite order perturbation theory predictions and discuss the construction of optimal observables.

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J. G. Koerner, F. Krajewski, A. A. Pivovarov. 1999-09-02. Asymptotic structure of perturbative series for tau lepton observables. https://doi.org/10.1007/s100529900279

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